Transpose an arbitrarily sized rectangular Matrix.

Task
Matrix transposition
You are encouraged to solve this task according to the task description, using any language you may know.

11l

F transpose(&matrix)
    V toRet = [[0] * matrix.len] * matrix[0].len
    L(row) (0 .< matrix.len)
        L(col) (0 .< matrix[row].len)
            toRet[col][row] = matrix[row][col]
    R toRet

V m = [[1, 2, 3, 4], [5, 6, 7, 8], [9, 10, 11, 12]]
print("Original")
print(m)
print("After Transposition")
print(transpose(&m))
Output:
Original
[[1, 2, 3, 4], [5, 6, 7, 8], [9, 10, 11, 12]]
After Transposition
[[1, 5, 9], [2, 6, 10], [3, 7, 11], [4, 8, 12]]

360 Assembly

...          
KN       EQU    3
KM       EQU    5
N        DC     AL2(KN)
M        DC     AL2(KM)
A        DS     (KN*KM)F           matrix a(n,m)
B        DS     (KM*KN)F           matrix b(m,n)
... 
*        b(j,i)=a(i,j)
*        transposition using Horner's formula
         LA     R4,0               i,from 1
         LA     R7,KN              to n
         LA     R6,1               step 1
LOOPI    BXH    R4,R6,ELOOPI       do i=1 to n
         LA     R5,0               j,from 1
         LA     R9,KM              to m
         LA     R8,1               step 1
LOOPJ    BXH    R5,R8,ELOOPJ       do j=1 to m
         LR     R1,R4              i
         BCTR   R1,0               i-1
         MH     R1,M               (i-1)*m
         LR     R2,R5              j
         BCTR   R2,0               j-1
         AR     R1,R2              r1=(i-1)*m+(j-1)
         SLA    R1,2               r1=((i-1)*m+(j-1))*itemlen
         L      R0,A(R1)           r0=a(i,j)
         LR     R1,R5              j
         BCTR   R1,0               j-1
         MH     R1,N               (j-1)*n
         LR     R2,R4              i
         BCTR   R2,0               i-1
         AR     R1,R2              r1=(j-1)*n+(i-1)
         SLA    R1,2               r1=((j-1)*n+(i-1))*itemlen
         ST     R0,B(R1)           b(j,i)=r0
         B      LOOPJ              next j
ELOOPJ   EQU    *                  out of loop j
         B      LOOPI              next i
ELOOPI   EQU    *                  out of loop i
...

68000 Assembly

Transpose2DArray_B:
	;INPUT:
	;A0 = POINTER TO SOURCE ARRAY
	;A1 = POINTER TO BACKUP AREA 
	;	(YOU NEED THE SAME AMOUNT OF FREE SPACE AS THE SOURCE ARRAY.)
	;	(IT'S YOUR RESPONSIBILITY TO KNOW WHERE THAT IS.)
	;D0.W = ARRAY ROW LENGTH-1
        ;D1.W = ARRAY COLUMN HEIGHT-1

	MOVEM.L D2-D7,-(SP)
		MOVE.W D0,D4	;width - this copy is our loop counter

.outerloop:
		MOVE.W D1,D7	;height
		MOVEQ.L #0,D3
		MOVE.W D0,D6	;width - this copy is used to offset the array
		ADDQ.L #1,D6

.innerloop:
		MOVE.B (A0,D3),(A1)+
		ADD.W D6,D3
		DBRA D7,.innerloop

		ADDA.L #1,A0
		DBRA D4,.outerloop

	MOVEM.L (SP)+,D2-D7
	RTS

ACL2

(defun cons-each (xs xss)
   (if (or (endp xs) (endp xss))
       nil
       (cons (cons (first xs) (first xss))
             (cons-each (rest xs) (rest xss)))))

(defun list-each (xs)
   (if (endp xs)
       nil
       (cons (list (first xs))
             (list-each (rest xs)))))

(defun transpose-list (xss)
   (if (endp (rest xss))
       (list-each (first xss))
       (cons-each (first xss)
                  (transpose-list (rest xss)))))

Action!

DEFINE PTR="CARD"

TYPE Matrix=[
  BYTE width,height
  PTR data] ;BYTE ARRAY

PROC PrintB2(BYTE b)
  IF b<10 THEN Put(32) FI
  PrintB(b)
RETURN

PROC PrintMatrix(Matrix POINTER m)
  BYTE i,j
  BYTE ARRAY d

  d=m.data
  FOR j=0 TO m.height-1
  DO
    FOR i=0 TO m.width-1
    DO
      PrintB2(d(j*m.width+i)) Put(32)
    OD
    PutE()
  OD
RETURN

PROC Create(MATRIX POINTER m BYTE w,h BYTE ARRAY a)
  m.width=w
  m.height=h
  m.data=a
RETURN

PROC Transpose(Matrix POINTER in,out)
  BYTE i,j
  BYTE ARRAY din,dout

  din=in.data
  dout=out.data
  out.width=in.height
  out.height=in.width
  FOR j=0 TO in.height-1
  DO
    FOR i=0 TO in.width-1
    DO
      dout(i*out.width+j)=din(j*in.width+i)
    OD
  OD
RETURN

PROC Main()
  MATRIX in,out
  BYTE ARRAY din(35),dout(35)
  BYTE i

  FOR i=0 TO 34
  DO
    din(i)=i
  OD
  Create(in,7,5,din)
  Create(out,0,0,dout)
  Transpose(in,out)

  PrintE("Input:")
  PrintMatrix(in)
  PutE() PrintE("Transpose:")
  PrintMatrix(out)
RETURN
Output:

Screenshot from Atari 8-bit computer

Input:
 0  1  2  3  4  5  6
 7  8  9 10 11 12 13
14 15 16 17 18 19 20
21 22 23 24 25 26 27
28 29 30 31 32 33 34

Transpose:
 0  7 14 21 28
 1  8 15 22 29
 2  9 16 23 30
 3 10 17 24 31
 4 11 18 25 32
 5 12 19 26 33
 6 13 20 27 34

ActionScript

In ActionScript, multi-dimensional arrays are created by making an "Array of arrays" where each element is an array.

function transpose( m:Array):Array
{
	//Assume each element in m is an array. (If this were production code, use typeof to be sure)

	//Each element in m is a row, so this gets the length of a row in m, 
	//which is the same as the number of rows in m transpose.
	var mTranspose = new Array(m[0].length);
	for(var i:uint = 0; i < mTranspose.length; i++)
	{
                //create a row
		mTranspose[i] = new Array(m.length);
                //set the row to the appropriate values
		for(var j:uint = 0; j < mTranspose[i].length; j++)
			mTranspose[i][j] = m[j][i];
	}
	return mTranspose;
}
var m:Array = [[1, 2, 3, 10],
	       [4, 5, 6, 11],
	       [7, 8, 9, 12]];
var M:Array = transpose(m);
for(var i:uint = 0; i < M.length; i++)
	trace(M[i]);

Ada

Transpose is a function of the standard Ada library provided for matrices built upon any floating-point or complex type. The relevant packages are Ada.Numerics.Generic_Real_Arrays and Ada.Numerics.Generic_Complex_Arrays, correspondingly.

This example illustrates use of Transpose for the matrices built upon the standard type Float:

with Ada.Numerics.Real_Arrays;  use Ada.Numerics.Real_Arrays;
with Ada.Text_IO;               use Ada.Text_IO; 
 
procedure Matrix_Transpose is
   procedure Put (X : Real_Matrix) is
      type Fixed is delta 0.01 range -500.0..500.0;
   begin
      for I in X'Range (1) loop
         for J in X'Range (2) loop
            Put (Fixed'Image (Fixed (X (I, J))));
         end loop;
         New_Line;
      end loop;
   end Put;
    
   Matrix : constant Real_Matrix :=
            (  (0.0, 0.1, 0.2, 0.3),
               (0.4, 0.5, 0.6, 0.7),
               (0.8, 0.9, 1.0, 1.1)
            );
begin
   Put_Line ("Before Transposition:");
   Put (Matrix);
   New_Line;
   Put_Line ("After Transposition:");
   Put (Transpose (Matrix));
end Matrix_Transpose;
Output:
Before Transposition:
 0.00 0.10 0.20 0.30
 0.40 0.50 0.60 0.70
 0.80 0.90 1.00 1.10

After Transposition:
 0.00 0.40 0.80
 0.10 0.50 0.90
 0.20 0.60 1.00
 0.30 0.70 1.10

Agda

module Matrix where

open import Data.Nat
open import Data.Vec

Matrix : (A : Set)      Set
Matrix A m n = Vec (Vec A m) n

transpose :  {A m n}  Matrix A m n  Matrix A n m
transpose [] = replicate []
transpose (xs  xss) = zipWith _∷_ xs (transpose xss)

a = (1  2  3  [])  (4  5  6  [])  []
b = transpose a

b evaluates to the following normal form:

(1  4  [])  (2  5  [])  (3  6  [])  []

ALGOL 68

Works with: ALGOL 68 version Revision 1 - no extensions to language used
Works with: ALGOL 68G version Any - tested with release 1.18.0-9h.tiny
main:(

  [,]REAL m=((1,  1,  1,   1),
             (2,  4,  8,  16),
             (3,  9, 27,  81),
             (4, 16, 64, 256),
             (5, 25,125, 625));

  OP ZIP = ([,]REAL in)[,]REAL:(
    [2 LWB in:2 UPB in,1 LWB in:1UPB in]REAL out;
    FOR i FROM LWB in TO UPB in DO
       out[,i]:=in[i,] 
    OD;
    out
  );

  PROC pprint = ([,]REAL m)VOID:(
    FORMAT real fmt = $g(-6,2)$; # width of 6, with no '+' sign, 2 decimals #
     FORMAT vec fmt = $"("n(2 UPB m-1)(f(real fmt)",")f(real fmt)")"$;
    FORMAT matrix fmt = $x"("n(UPB m-1)(f(vec fmt)","lxx)f(vec fmt)");"$;
    # finally print the result #
    printf((matrix fmt,m))
  );

  printf(($x"Transpose:"l$));
  pprint((ZIP m))
)
Output:

Transpose:
((  1.00,  2.00,  3.00,  4.00,  5.00),
 (  1.00,  4.00,  9.00, 16.00, 25.00),
 (  1.00,  8.00, 27.00, 64.00,125.00),
 (  1.00, 16.00, 81.00,256.00,625.00));

Amazing Hopper

#include<hopper.h>
#proto showarraydata(_X_)
main:
  .stack 12
  nCols=0, nRows=0,nDims=0
  A=-1,{5,11} rand array(A),mulby(10),ceil,mov(A)
  {"ORIGINAL ARRAY :\n",A}

  _show array data(A)
  
  /* transpose */
  TA=0,{nCols,nRows} nan array(TA)
  Limit = nRows
  {nRows}gthan(nCols) do{ Limit = nCols }

  for (i=1, {i} lethan (Limit), ++i)
     [i,i:end]get(A), [i:end,i]put(TA)
     [i:end,i]get(A), [i,i:end]put(TA)
  next
  clear mark
  {"ARRAY TRANSPOSE:\n",TA}println
  _show array data(TA)
exit(0)

.locals
show array data(A)
  {"\nSIZE ARRAY : "},size=0,size(A),cpy(size),
  dims(size,nDims)
  rows(size,nRows)
  cols(size,nCols)
  {"\nDIMENSION = ",nDims,"; ROWS = ",nRows,"; COLS = ",nCols,"\n"}, println
back
Output:
ORIGINAL ARRAY :
6 6 8 3 2 6 9 3 5 3 10
6 7 10 3 9 6 5 8 8 1 10
2 3 7 10 7 9 3 7 3 8 2
10 1 3 6 9 6 1 1 5 7 7
5 9 6 1 4 3 8 4 2 10 7

SIZE ARRAY : 2 5 11
DIMENSION = 2; ROWS = 5; COLS = 11

ARRAY TRANSPOSE:
6 6 2 10 5
6 7 3 1 9
8 10 7 3 6
3 3 10 6 1
2 9 7 9 4
6 6 9 6 3
9 5 3 1 8
3 8 7 1 4
5 8 3 5 2
3 1 8 7 10
10 10 2 7 7

SIZE ARRAY : 2 11 5
DIMENSION = 2; ROWS = 11; COLS = 5

APL

If M is a matrix, ⍉M is its transpose. For example,

      3 3⍴⍳10
1 2 3
4 5 6
7 8 9
       3 3⍴⍳10
1 4 7
2 5 8
3 6 9

AppleScript

We can do this iteratively, by manually setting up two nested loops, and initialising iterators and empty lists,

on run
    transpose([[1, 2, 3], [4, 5, 6], [7, 8, 9], [10, 11, 12]])

    --> {{1, 4, 7, 10}, {2, 5, 8, 11}, {3, 6, 9, 12}}
end run

on transpose(xss)
    set lstTrans to {}
    
    repeat with iCol from 1 to length of item 1 of xss
        set lstCol to {}
        
        repeat with iRow from 1 to length of xss
            set end of lstCol to item iCol of item iRow of xss
        end repeat
        
        set end of lstTrans to lstCol
    end repeat
    
    return lstTrans
end transpose


or, if our library contains some generic basics like map(), and we use the AS script mechanism for closures, we can delegate the iterative details and write transpose() a little more declaratively, without having to reach for set, repeat, or return inside its definition.

Translation of: JavaScript
------------------------ TRANSPOSE -----------------------

-- transpose :: [[a]] -> [[a]]
on transpose(xss)
    script column
        on |λ|(_, iCol)
            script row
                on |λ|(xs)
                    item iCol of xs
                end |λ|
            end script
            
            map(row, xss)
        end |λ|
    end script
    
    map(column, item 1 of xss)
end transpose


--------------------------- TEST -------------------------
on run
    transpose([[1, 2, 3], [4, 5, 6], [7, 8, 9], [10, 11, 12]])
    
    --> {{1, 4, 7, 10}, {2, 5, 8, 11}, {3, 6, 9, 12}}
end run


-------------------- GENERIC FUNCTIONS -------------------

-- map :: (a -> b) -> [a] -> [b]
on map(f, xs)
    tell mReturn(f)
        set lng to length of xs
        set lst to {}
        repeat with i from 1 to lng
            set end of lst to |λ|(item i of xs, i, xs)
        end repeat
        return lst
    end tell
end map

-- Lift 2nd class handler function into 1st class script wrapper 
-- mReturn :: Handler -> Script
on mReturn(f)
    if class of f is script then
        f
    else
        script
            property |λ| : f
        end script
    end if
end mReturn
Output:
{{1, 4, 7, 10}, {2, 5, 8, 11}, {3, 6, 9, 12}}

Arturo

transpose: function [a][
    X: size a
    Y: size first a
    result: array.of: @[Y X] 0

    loop 0..X-1 'i [
        loop 0..Y-1 'j [
            result\[j]\[i]: a\[i]\[j]
        ]
    ]
    return result
]

arr: [
    [ 0 1 2 3 4  ]
    [ 5 6 7 8 9  ]
    [ 1 0 0 0 42 ]
]

loop arr 'row -> print row
print "-------------"
loop transpose arr 'row -> print row
Output:
0 1 2 3 4 
5 6 7 8 9 
1 0 0 0 42 
-------------
0 5 1 
1 6 0 
2 7 0 
3 8 0 
4 9 42

AutoHotkey

a = a
m = 10
n = 10
Loop, 10
{
  i := A_Index - 1
  Loop, 10
  {
    j := A_Index - 1
    %a%%i%%j% := i - j
  }
}
before := matrix_print("a", m, n)
transpose("a", m, n)
after := matrix_print("a", m, n)  
MsgBox % before . "`ntransposed:`n" . after
Return

transpose(a, m, n)
{
  Local i, j, row, matrix
  Loop, % m 
  {
    i := A_Index - 1
    Loop, % n 
    {
      j := A_Index - 1
      temp%i%%j% := %a%%j%%i%
    }
  }
  Loop, % m 
  {
    i := A_Index - 1
    Loop, % n 
    {
      j := A_Index - 1
      %a%%i%%j% := temp%i%%j%
    }
  }
}

matrix_print(a, m, n)
{
  Local i, j, row, matrix
  Loop, % m 
  {
    i := A_Index - 1
    row := ""
    Loop, % n 
    {
      j := A_Index - 1
      row .= %a%%i%%j% . ","
    }
    StringTrimRight, row, row, 1
    matrix .= row . "`n"
  }
  Return matrix
}

Using Objects

Transpose(M){
	R := []
	for i, row in M
		for j, col in row
			R[j,i] := col
	return R
}

Examples:

Matrix := [[1,2,3],[4,5,6],[7,8,9],[10,11,12]]
MsgBox % 	""
		. "Original Matrix :`n" 		Print(Matrix) 
		. "`nTransposed Matrix :`n" 	Print(Transpose(Matrix))

Print(M){
	for i, row in M
		for j, col in row
			Res .= (A_Index=1?"":"`t") col (Mod(A_Index,M[1].MaxIndex())?"":"`n")
	return Trim(Res,"`n")
}
Output:
Original Matrix :
1	2	3
4	5	6
7	8	9
10	11	12

Transposed Matrix :
1	4	7	10
2	5	8	11
3	6	9	12

AWK

# syntax: GAWK -f MATRIX_TRANSPOSITION.AWK filename
{   if (NF > nf) {
        nf = NF
    }
    for (i=1; i<=nf; i++) {
        row[i] = row[i] $i " "
    }
}
END {
    for (i=1; i<=nf; i++) {
        printf("%s\n",row[i])
    }
    exit(0)
}

input:

1 2 3 4
5 6 7 8
9 10 11 12
Output:
1 5 9
2 6 10
3 7 11
4 8 12

Using 2D-Arrays

# Usage: GAWK -f MATRIX_TRANSPOSITION.AWK filename
{
    i = NR
    for (j = 1; j <= NF; j++) {
        a[i,j] = $j
    }
    ranka1 = i
    ranka2 = max(ranka2, NF)
}
END {
    rankb1 = ranka2
    rankb2 = ranka1
    b[rankb1, rankb2] = 0
    transpose_matrix(b, a)
    for (i = 1; i <= rankb1; i++) {
        for (j = 1; j <= rankb2; j++) {
            printf("%g%c", b[i,j], j < rankb2 ? " " : "\n");
        }
    }
}
function transpose_matrix(target, source,     key, idx) {
    for (key in source) {
        split(key, idx, SUBSEP)
        target[idx[2], idx[1]] = source[idx[1], idx[2]]
    }
}
function max(m, n) {
    return m > n ? m : n
}

Input:

1 2 3
4 5 6
Output:
1. 4.
2. 5.
3. 6.

BASIC

Works with: QuickBasic version 4.5
CLS
DIM m(1 TO 5, 1 TO 4) 'any dimensions you want

'set up the values in the array
FOR rows = LBOUND(m, 1) TO UBOUND(m, 1) 'LBOUND and UBOUND can take a dimension as their second argument
       FOR cols = LBOUND(m, 2) TO UBOUND(m, 2)
       m(rows, cols) = rows ^ cols 'any formula you want
       NEXT cols
NEXT rows

'declare the new matrix
DIM trans(LBOUND(m, 2) TO UBOUND(m, 2), LBOUND(m, 1) TO UBOUND(m, 1))

'copy the values
FOR rows = LBOUND(m, 1) TO UBOUND(m, 1)
       FOR cols = LBOUND(m, 2) TO UBOUND(m, 2)
       trans(cols, rows) = m(rows, cols)
       NEXT cols
NEXT rows

'print the new matrix
FOR rows = LBOUND(trans, 1) TO UBOUND(trans, 1)
       FOR cols = LBOUND(trans, 2) TO UBOUND(trans, 2)
       PRINT trans(rows, cols);
       NEXT cols
PRINT
NEXT rows


BASIC256

arraybase 1
dim matriz= {{78,19,30,12,36}, {49,10,65,42,50}, {30,93,24,78,10}, {39,68,27,64,29}}
dim mtranspuesta(matriz[,?], matriz[?,])

for fila = 1 to matriz[?,]
    for columna = 1 to matriz[,?]
		print matriz[fila, columna]; " ";
		mtranspuesta[columna, fila] = matriz[fila, columna]
	next columna
	print
next fila
print

for fila = 1 to mtranspuesta[?,]
    for columna = 1 to mtranspuesta[,?]
		print mtranspuesta[fila, columna]; " ";
    next columna
	print
next fila
end


BBC BASIC

      INSTALL @lib$+"ARRAYLIB"
      
      DIM matrix(3,4), transpose(4,3)
      matrix() = 78,19,30,12,36,49,10,65,42,50,30,93,24,78,10,39,68,27,64,29
      
      PROC_transpose(matrix(), transpose())
      
      FOR row% = 0 TO DIM(matrix(),1)
        FOR col% = 0 TO DIM(matrix(),2)
          PRINT ;matrix(row%,col%) " ";
        NEXT
        PRINT
      NEXT row%
      
      PRINT
      
      FOR row% = 0 TO DIM(transpose(),1)
        FOR col% = 0 TO DIM(transpose(),2)
          PRINT ;transpose(row%,col%) " ";
        NEXT
        PRINT
      NEXT row%
Output:
78 19 30 12 36
49 10 65 42 50
30 93 24 78 10
39 68 27 64 29

78 49 30 39
19 10 93 68
30 65 24 27
12 42 78 64
36 50 10 29


BQN

Translation of: APL

If M is a matrix, ⍉M is its transpose. For example,

   33⥊↕9
┌─
 0 1 2
  3 4 5
  6 7 8
        
   33⥊↕9
┌─
 0 3 6
  1 4 7
  2 5 8
        

Burlesque

blsq ) {{78 19 30 12 36}{49 10 65 42 50}{30 93 24 78 10}{39 68 27 64 29}}tpsp
78 49 30 39
19 10 93 68
30 65 24 27
12 42 78 64
36 50 10 29

C

Transpose a 2D double array.

#include <stdio.h>

void transpose(void *dest, void *src, int src_h, int src_w)
{
	int i, j;
	double (*d)[src_h] = dest, (*s)[src_w] = src;
	for (i = 0; i < src_h; i++)
		for (j = 0; j < src_w; j++)
			d[j][i] = s[i][j];
}

int main()
{
	int i, j;
	double a[3][5] = {{ 0, 1, 2, 3, 4 },
			  { 5, 6, 7, 8, 9 },
			  { 1, 0, 0, 0, 42}};
	double b[5][3];
	transpose(b, a, 3, 5);

	for (i = 0; i < 5; i++)
		for (j = 0; j < 3; j++)
			printf("%g%c", b[i][j], j == 2 ? '\n' : ' ');
	return 0;
}

Transpose a matrix of size w x h in place with only O(1) space and without moving any element more than once. See the Wikipedia article for more information.

#include <stdio.h>

void transpose(double *m, int w, int h)
{
	int start, next, i;
	double tmp;

	for (start = 0; start <= w * h - 1; start++) {
		next = start;
		i = 0;
		do {	i++;
			next = (next % h) * w + next / h;
		} while (next > start);
		if (next < start || i == 1) continue;

		tmp = m[next = start];
		do {
			i = (next % h) * w + next / h;
			m[next] = (i == start) ? tmp : m[i];
			next = i;
		} while (next > start);
	}
}

void show_matrix(double *m, int w, int h)
{
	int i, j;
	for (i = 0; i < h; i++) {
		for (j = 0; j < w; j++)
			printf("%2g ", m[i * w + j]);
		putchar('\n');
	}
}

int main(void)
{
	int i;
	double m[15];
	for (i = 0; i < 15; i++) m[i] = i + 1;

	puts("before transpose:");
	show_matrix(m, 3, 5);

	transpose(m, 3, 5);

	puts("\nafter transpose:");
	show_matrix(m, 5, 3);

	return 0;
}
Output:
before transpose:
 1  2  3 
 4  5  6 
 7  8  9 
10 11 12 
13 14 15 

after transpose:
 1  4  7 10 13 
 2  5  8 11 14 
 3  6  9 12 15 

C#

using System;
using System.Text;

namespace prog
{
	class MainClass
	{						
		public static void Main (string[] args)
		{
			double[,] m = { {1,2,3},{4,5,6},{7,8,9} };
			
			double[,] t = Transpose( m );	
			
			for( int i=0; i<t.GetLength(0); i++ )
			{
				for( int j=0; j<t.GetLength(1); j++ )		
					Console.Write( t[i,j] + "  " );
				Console.WriteLine("");
			}
		}
		
		public static double[,] Transpose( double[,] m )
		{
			double[,] t = new double[m.GetLength(1),m.GetLength(0)];
			for( int i=0; i<m.GetLength(0); i++ )
				for( int j=0; j<m.GetLength(1); j++ )
					t[j,i] = m[i,j];			
			
			return t;
		}
	}
}

C++

C++ does not have a built-in or standard-library Matrix class, so many users have rolled their own. Boost supplies one (boost::numeric::ublas::matrix<element_t> in the example below). Many users have rolled their own matrix class; a (long) code sample below shows such a class.

Library: Boost.uBLAS
#include <boost/numeric/ublas/matrix.hpp>
#include <boost/numeric/ublas/io.hpp>

int main()
{
  using namespace boost::numeric::ublas;

  matrix<double> m(3,3);

  for(int i=0; i!=m.size1(); ++i)
    for(int j=0; j!=m.size2(); ++j)
      m(i,j)=3*i+j;

  std::cout << trans(m) << std::endl;
}
Output:
 [3,3]((0,3,6),(1,4,7),(2,5,8))

Generic solution

main.cpp
#include <iostream>
#include "matrix.h"

#if !defined(ARRAY_SIZE)
    #define ARRAY_SIZE(x) (sizeof((x)) / sizeof((x)[0]))
#endif

template<class T>
void printMatrix(const Matrix<T>& m) {
    std::cout << "rows = " << m.rowNum() << "   columns = " << m.colNum() << std::endl;
    for (unsigned int i = 0; i < m.rowNum(); i++) {
        for (unsigned int j = 0; j < m.colNum(); j++) {
            std::cout <<  m[i][j] << "  ";
        }
        std::cout << std::endl;
    }
} /* printMatrix() */

int main() {
    int  am[2][3] = {
        {1,2,3},
        {4,5,6},
    };

    Matrix<int> a(ARRAY_SIZE(am), ARRAY_SIZE(am[0]), am[0], ARRAY_SIZE(am)*ARRAY_SIZE(am[0]));

    try {
        std::cout << "Before transposition:" << std::endl;
        printMatrix(a);
        std::cout << std::endl;
        a.transpose();
        std::cout << "After transposition:" << std::endl;
        printMatrix(a);
    } catch (MatrixException& e) {
        std::cerr << e.message() << std::endl;
        return e.errorCode();
    }

} /* main() */
matrix.h
#ifndef _MATRIX_H
#define	_MATRIX_H

#include <sstream>
#include <string>
#include <vector>
#include <algorithm>

#define MATRIX_ERROR_CODE_COUNT 5
#define MATRIX_ERR_UNDEFINED "1 Undefined exception!"
#define MATRIX_ERR_WRONG_ROW_INDEX "2 The row index is out of range."
#define MATRIX_ERR_MUL_ROW_AND_COL_NOT_EQUAL "3 The row number of second matrix must be equal with the column number of first matrix!"
#define MATRIX_ERR_MUL_ROW_AND_COL_BE_GREATER_THAN_ZERO "4 The number of rows and columns must be greater than zero!"
#define MATRIX_ERR_TOO_FEW_DATA "5 Too few data in matrix."

class MatrixException {
private:
    std::string message_;
    int errorCode_;
public:
    MatrixException(std::string message = MATRIX_ERR_UNDEFINED);

    inline std::string message() {
        return message_;
    };

    inline int errorCode() {
        return errorCode_;
    };
};

MatrixException::MatrixException(std::string message) {
    errorCode_ = MATRIX_ERROR_CODE_COUNT + 1;
    std::stringstream ss(message);
    ss >> errorCode_;
    if (errorCode_ < 1) {
        errorCode_ = MATRIX_ERROR_CODE_COUNT + 1;
    }
    std::string::size_type pos = message.find(' ');
    if (errorCode_ <= MATRIX_ERROR_CODE_COUNT && pos != std::string::npos) {
        message_ = message.substr(pos + 1);
    } else {
        message_ = message + " (This an unknown and unsupported exception!)";
    }
}

/**
 * Generic class for matrices.
 */
template <class T>
class Matrix {
private:
    std::vector<T> v; // the data of matrix
    unsigned int m;   // the number of rows
    unsigned int n;   // the number of columns
protected:

    virtual void clear() {
        v.clear();
        m = n = 0;
    }
public:

    Matrix() {
        clear();
    }
    Matrix(unsigned int, unsigned int, T* = 0, unsigned int = 0);
    Matrix(unsigned int, unsigned int, const std::vector<T>&);

    virtual ~Matrix() {
        clear();
    }
    Matrix& operator=(const Matrix&);
    std::vector<T> operator[](unsigned int) const;
    Matrix operator*(const Matrix&);
    void transpose();

    inline unsigned int rowNum() const {
        return m;
    }

    inline unsigned int colNum() const {
        return n;
    }

    inline unsigned int size() const {
        return v.size();
    }

    inline void add(const T& t) {
        v.push_back(t);
    }
};

template <class T>
Matrix<T>::Matrix(unsigned int row, unsigned int col, T* data, unsigned int dataLength) {
    clear();
    if (row > 0 && col > 0) {
        m = row;
        n = col;
        unsigned int mxn = m * n;
        if (dataLength && data) {
            for (unsigned int i = 0; i < dataLength && i < mxn; i++) {
                v.push_back(data[i]);
            }
        }
    }
}

template <class T>
Matrix<T>::Matrix(unsigned int row, unsigned int col, const std::vector<T>& data) {
    clear();
    if (row > 0 && col > 0) {
        m = row;
        n = col;
        unsigned int mxn = m * n;
        if (data.size() > 0) {
            for (unsigned int i = 0; i < mxn && i < data.size(); i++) {
                v.push_back(data[i]);
            }
        }
    }
}

template<class T>
Matrix<T>& Matrix<T>::operator=(const Matrix<T>& other) {
    clear();
    if (other.m > 0 && other.n > 0) {
        m = other.m;
        n = other.n;
        unsigned int mxn = m * n;
        for (unsigned int i = 0; i < mxn && i < other.size(); i++) {
            v.push_back(other.v[i]);
        }
    }
    return *this;
}

template<class T>
std::vector<T> Matrix<T>::operator[](unsigned int index) const {
    std::vector<T> result;
    if (index >= m) {
        throw MatrixException(MATRIX_ERR_WRONG_ROW_INDEX);
    } else if ((index + 1) * n > size()) {
        throw MatrixException(MATRIX_ERR_TOO_FEW_DATA);
    } else {
        unsigned int begin = index * n;
        unsigned int end = begin + n;
        for (unsigned int i = begin; i < end; i++) {
            result.push_back(v[i]);
        }
    }
    return result;
}

template<class T>
Matrix<T> Matrix<T>::operator*(const Matrix<T>& other) {
    Matrix result(m, other.n);
    if (n != other.m) {
        throw MatrixException(MATRIX_ERR_MUL_ROW_AND_COL_NOT_EQUAL);
    } else if (m <= 0 || n <= 0 || other.n <= 0) {
        throw MatrixException(MATRIX_ERR_MUL_ROW_AND_COL_BE_GREATER_THAN_ZERO);
    } else if (m * n > size() || other.m * other.n > other.size()) {
        throw MatrixException(MATRIX_ERR_TOO_FEW_DATA);
    } else {
        for (unsigned int i = 0; i < m; i++) {
            for (unsigned int j = 0; j < other.n; j++) {
                T temp = v[i * n] * other.v[j];
                for (unsigned int k = 1; k < n; k++) {
                    temp += v[i * n + k] * other.v[k * other.n + j];
                }
                result.v.push_back(temp);
            }
        }
    }
    return result;
}

template<class T>
void Matrix<T>::transpose() {
    if (m * n > size()) {
        throw MatrixException(MATRIX_ERR_TOO_FEW_DATA);
    } else {
        std::vector<T> v2;
        std::swap(v, v2);
        for (unsigned int i = 0; i < n; i++) {
            for (unsigned int j = 0; j < m; j++) {
                v.push_back(v2[j * n + i]);
            }
        }
        std::swap(m, n);
    }
}

#endif	/* _MATRIX_H */
Output:
Before transposition:
rows = 2   columns = 3
1  2  3  
4  5  6  

After transposition:
rows = 3   columns = 2
1  4  
2  5  
3  6

Easy Mode

#include <iostream>

int main(){
    const int l = 5;
    const int w = 3;
    int m1[l][w] = {{1,2,3}, {4,5,6}, {7,8,9}, {10,11,12}, {13,14,15}};
    int m2[w][l];
    
    for(int i=0; i<w; i++){
        for(int x=0; x<l; x++){
            m2[i][x]=m1[x][i];
        }
    }

    // This is just output...
   
    std::cout << "Before:";
    for(int i=0; i<l; i++){
        std::cout << std::endl;
        for(int x=0; x<w; x++){
            std::cout << m1[i][x] << " ";
        }
    }
    
    std::cout << "\n\nAfter:";
    for(int i=0; i<w; i++){
        std::cout << std::endl;
        for(int x=0; x<l; x++){
            std::cout << m2[i][x] << " ";
        }
    }
    
    std::cout << std::endl;
    
    return 0;
}
Output:
Before:
1 2 3 
4 5 6 
7 8 9 
10 11 12 
13 14 15 

After:
1 4 7 10 13 
2 5 8 11 14 
3 6 9 12 15

Clojure

(defmulti matrix-transpose
  "Switch rows with columns."
  class)

(defmethod matrix-transpose clojure.lang.PersistentList
  [mtx]
  (apply map list mtx))

(defmethod matrix-transpose clojure.lang.PersistentVector
  [mtx]
  (apply mapv vector mtx))
Output:
=> (matrix-transpose [[1 2 3] [4 5 6]])
[[1 4] [2 5] [3 6]]

CoffeeScript

transpose = (matrix) ->
    (t[i] for t in matrix) for i in [0...matrix[0].length]
Output:
> transpose [[1,2,3],[4,5,6]]

[[1,4],[2,5],[3,6]]

Common Lisp

If the matrix is given as a list:

(defun transpose (m)
  (apply #'mapcar #'list m))

If the matrix A is given as a 2D array:

;; Transpose a mxn matrix A to a nxm matrix B=A'.
(defun mtp (A)
  (let* ((m (array-dimension A 0))
         (n (array-dimension A 1))
         (B (make-array `(,n ,m) :initial-element 0)))
    (loop for i from 0 below m do
          (loop for j from 0 below n do
                (setf (aref B j i)
                      (aref A i j))))
    B))

D

Standard Version

void main() {
    import std.stdio, std.range;

    /*immutable*/ auto M = [[10, 11, 12, 13],
                            [14, 15, 16, 17],
                            [18, 19, 20, 21]];
    writefln("%(%(%2d %)\n%)", M.transposed);
}
Output:
10 14 18
11 15 19
12 16 20
13 17 21

Locally Procedural Style

T[][] transpose(T)(in T[][] m) pure nothrow {
    auto r = new typeof(return)(m[0].length, m.length);
    foreach (immutable nr, const row; m)
        foreach (immutable nc, immutable c; row)
            r[nc][nr] = c;
    return r;
}

void main() {
    import std.stdio;

    immutable M = [[10, 11, 12, 13],
                   [14, 15, 16, 17],
                   [18, 19, 20, 21]];
    writefln("%(%(%2d %)\n%)", M.transpose);
}

Same output.

Functional Style

import std.stdio, std.algorithm, std.range, std.functional;

auto transpose(T)(in T[][] m) pure nothrow {
    return m[0].length.iota.map!(curry!(transversal, m));
}

void main() {
    immutable M = [[10, 11, 12, 13],
                   [14, 15, 16, 17],
                   [18, 19, 20, 21]];
    writefln("%(%(%2d %)\n%)", M.transpose);
}

Same output.

Delphi

See #Pascal;

DuckDB

In this entry, two representations of an m x n matrix are considered:

1. the representation as a table with three columns: (i,j,value);

2. the representation as a table with m rows and either n or n+1 columns, depending on whether a row id is included.

The SQL for computing the transposition of a matrix represented in the (i,j,value) form is trivial since we have simply to interchange the i and j labels:

select j as i, i as j, value from A;

Handling the matrix-like representation thus boils down to converting between the two representations. In brief:

  • PIVOT can be used to create the matrix-like representation of an (i,j,value) table;
  • UNPIVOT can be used to convert an (i,j,value) table to the corresponding matrix-like representation.

The examples below give the details.

create or replace table A (i integer, j integer, value float );
insert into A values
  (1, 1, 1),
  (1, 2, 2),
  (1, 3, 3),
  (2, 1, 2),
  (2, 2, 5),
  (2, 3, 7);

# transposition
create or replace table AT as
  (select j as i, i as j, value from A);

.print The matrix-like representation of A:
create or replace table AMatrix as (pivot A on j using max(value) order by i);
from AMatrix;

.print Convert the matrix-like representation back to the (i,j,value) representation:
unpivot AMatrix on columns('^[1-9]') into name j VALUE value;

.print The matrix-like representation of "A transpose":
pivot AT on j using max(value) order by i;
Output:
The matrix-like representation of A:
┌───────┬───────┬───────┬───────┐
│   i   │   1   │   2   │   3   │
│ int32 │ float │ float │ float │
├───────┼───────┼───────┼───────┤
│     1 │   1.0 │   2.0 │   3.0 │
│     2 │   2.0 │   5.0 │   7.0 │
└───────┴───────┴───────┴───────┘
Convert the matrix-like representation back to the (i,j,value) representation:
┌───────┬─────────┬───────┐
│   i   │    j    │ value │
│ int32 │ varchar │ float │
├───────┼─────────┼───────┤
│     1 │ 1       │   1.0 │
│     1 │ 2       │   2.0 │
│     1 │ 3       │   3.0 │
│     2 │ 1       │   2.0 │
│     2 │ 2       │   5.0 │
│     2 │ 3       │   7.0 │
└───────┴─────────┴───────┘
The matrix-like representation of "A transpose":
┌───────┬───────┬───────┐
│   i   │   1   │   2   │
│ int32 │ float │ float │
├───────┼───────┼───────┤
│     1 │   1.0 │   2.0 │
│     2 │   2.0 │   5.0 │
│     3 │   3.0 │   7.0 │
└───────┴───────┴───────┘

EasyLang

proc transpose . m[][] .
   len n[][] len m[1][]
   for i to len n[][]
      for j to len m[][]
         n[i][] &= m[j][i]
      .
   .
   swap n[][] m[][]
.
m[][] = [ [ 1 2 3 4 ] [ 5 6 7 8 ] [ 9 10 11 12 ] ]
print m[][]
print ""
transpose m[][]
print m[][]
Output:
[
 [ 1 2 3 4 ]
 [ 5 6 7 8 ]
 [ 9 10 11 12 ]
]

[
 [ 1 5 9 ]
 [ 2 6 10 ]
 [ 3 7 11 ]
 [ 4 8 12 ]
]

EchoLisp

(lib 'matrix)

(define M (list->array (iota 6) 3 2))
(array-print M)
  0   1 
  2   3 
  4   5 
(array-print (matrix-transpose M))
  0   2   4 
  1   3   5

EDSAC order code

In these two programs the matrix elements are stored in consecutive memory locations, in row-major order (that is, the 1st row from left to right, then the 2nd row, etc). For simplicity, matrix elements are short values, each occupying one memory location. The programs could be modified so that each element occupies two memory locations, as in the EDSAC library subroutines for vectors and matrices.

Create a new matrix

  [Demo of matrix transposition. Not in place, creates a new matrix.
   EDSAC, Initial Orders 2.]
             ..PZ      [blank tape and terminator]
             T   50 K  [to call matrix transpose subroutine with 'G X']
             P  200 F  [address of matrix transpose subroutine]
             T   47 K  [to call matrix print subroutine with 'G M']
             P  100 F  [address of matrix print subroutine]
             T   46 K  [to call print subroutine with 'G N']
             P   56 F  [address of print subroutine (EDSAC library P1)]

  [Subroutine to transpose a matrix of 17-bit real numbers, not in place.
   Caller must ensure original and transpose don't overlap.
   Parameters, all in the address field (i.e. denote n by P n F)
   10F = width (number of columns)
   11F = height (number of rows)
   12F = start address of input matrix
   13F = start address of output matrix]
             E25K  TX  GK

    [The subroutine loads elements by working down each column in turn.
     Elements are stored at consecutive locations in the transposed matrix.]
             A3F  T31@         [set up return to caller]
             A13F  A33@  T14@  [initialize T order for storing transpose]
             A12F  A32@  U13@  [initialize A order for loading original]
             T36@              [also save as A order for top of current column]
             S10 F             [negative of width]
        [10] T35@              [initialize negative counter]
             S11 F             [negative of height]
        [12] T34@              [initialize negative counter]
        [13] AF                [maunfactured order; load matrix element]
        [14] TF                [maunfactured order; store matrix element]
             A14@  A2F  T14@   [update address in T order]
             A13@  A10F  T13@  [update address in A order]
             A34@  A2F  G12@   [inner loop till finished this column]
             A36@  A2F  U36@  T13@  [update address for start of column]
             A35@  A2F  G10@   [outer loop till finished all columns]
        [31] ZF  [exit]
        [32] AF  [added to an address to make A order for that address]
        [33] TF  [added to an address to make T order for that address]
        [34] PF  [negative counter for rows]
        [35] PF  [negative counter for columns]
        [36] AF  [load order for first element in current column]

  [Subroutine to print a matrix of 17-bit real numbers.
   Straightforward, so given in condensed form.
   Parameters (in the address field, i.e. pass n as PnF):
   10F = width (number of columns)
   11F = height (number of rows)
   12F = start address of matrix
   13F = number of decimals]
               E25K  TM
    GKA3FT30@A13FT18@A12FA31@T14@S11FT36@S10FT37@O34@O35@TDAFT1FA16@
    GN  [call library subroutine P1]
    PFA14@A2FT14@A37@A2FG10@O32@O33@A36@A2FG8@ZFAF@F&F!FMFPFPF

  [Library subroutine P1.
   Prints number in 0D to n places of decimals, where
   n is specified by 'P n F' pseudo-order after subroutine call.]
             E25K  TN
   GKA18@U17@S20@T5@H19@PFT5@VDUFOFFFSFL4FTDA5@A2FG6@EFU3FJFM1F

   [Main routine]
             PK T300K GK
      [Constants]
         [0] #F     [figures shift on teleprinter]
         [1] @F     [carriage return]
         [2] &F     [line feed]
         [3] P3F    [number of columns (in address field)]
         [4] P5F    [number of rows (in address field)]
         [5] P400F  [address of matrix]
         [6] P500F  [address of transposed matrix]
         [7] P2F    [number of decimals when printing matrix]
         [8] TF     [add to address to make T order]
         [9] P328F  [0.0100097...., matrix elements are multiples of this]
      [Variables]
        [10] PF     [matrix element, initialized to 0.00]
        [11] PF     [negative counter]

           [Enter with acc = 0]
        [12] O@     [set figures mode on teleprinter]
             A5@    [address of matrix]
             A8@    [make T order to store first elememt]
             T24@   [plant in code]
             H4@  N3@  L64F  L32F  [acc := negative number of entries]
        [20] T11@   [initialize negative counter]
             A10@  A9@  U10@  [increment matrix element]
        [24] TF               [store in matrix]
             A24@  A2F  T24@  [inc store address]
             A11@  A2F  G20@  [inc negative counter, loop till zero]

           [Matrix is set up, now print it]
             A3@  T10F  [10F := width]
             A4@  T11F  [11F := height]
             A5@  T12F  [12F := address of matrix]
             A7@  T13F  [13F := number of decimals]
        [39] A39@  GM   [call print subroutine]
             O1@  O2@   [add CR LF]

           [Transpose matrix: 10F, 11F, 12F stay the same]
             A6@  T13F  [13F := address of transpose]
        [45] A45@  GX   [call transpose routine]

           [Print transpose]
             A10F  TF  A11F  T10F  AF  T11F  [swap width and height]
             A13F  T12F [12F := address of transpose]
             A7@  T13F  [13F := number of decimals]
        [57] A57@  GM   [call print subroutine]

             O@    [figures mode, dummy to flush teleprinter buffer]
             ZF    [stop]
             E12Z  [enter at 12 (relative)]
             PF    [accumulator = 0 on entry]
Output:
 .01 .02 .03
 .04 .05 .06
 .07 .08 .09
 .10 .11 .12
 .13 .14 .15

 .01 .04 .07 .10 .13
 .02 .05 .08 .11 .14
 .03 .06 .09 .12 .15

Transpose in place

Translation of: C

That's a neat C program after the complications on Wikipedia. The way EDSAC handles arrays makes it convenient to modify the second half of the program. In C, the updated value of "next" has to be parked in another variable until m[next] (old "next") has been assigned to. In EDSAC, the instruction that assigns to m[next] can be planted before "next" is updated, and won't be affected by that update. Once the EDSAC program has been modified in this way, the code to update "next" is the same in both halves of the program and can be taken out as a subroutine.

[Transpose a matrix in place. EDSAC, Initial Orders 2.]
            ..PZ   [blank tape and terminator]
            T50K   [to call matrix transpose with 'G X']
            P160F  [address of matrix transpose subroutine]
            T47K   [to call matrix print subroutine with 'G M']
            P120F  [address of matrix print subroutine]
            T46K   [to call print subroutine with 'G N']
            P56F   [address of print subroutine (P1 in EDSAC library)]
            T48K   [to call division subroutine with 'G &']
            P77F   [address of division subroutine]

 [Subroutine to transpose a matrix of 17-bit values in place.
  Translated and slightly modified from C version on Rosetta Code website.
  Parameters, all in the address field (i.e. n is stored as P n F):
  10F = width (number of columns, "w" in C program)
  11F = height (number of rows, "h" in C program)
  12F = start address of matrix]
           E25K  TX  GK
           A3F  T64@               [set up return to caller]
           H10F  V11F  L32F  L64F  [acc := size of matrix as width*height]
           T84@  T85@              [store size; C variable start := 0]
      [8]  TF  A85@  T86@  T87@    [set C variables, next := start, i := 0]
     [12]  TF  A87@  A2F  T87@     [i++]
           A16@  G65@              [call subroutine to update "next"]
           A85@  S86@  G12@        [acc := start - next, loop back if < 0]
      [Skip to location 58 if acc > 0 or i = 1.
       We already know that acc >= 0 and i > 0.]
           S2F  E58@               [subtract 1 from acc, skip if still >= 0]
           S2F  A87@  G58@         [acc := -2 + i, skip if < 0]
      [The assignment next := start in the C program is unnecessary]
           TF  A86@  A12F  A81@  T31@  [make and plant order to load m{next}]
     [31]  AF  T83@                [tmp := m{next}]
     [33]  TF  [clear acc; also added to an address to make T order for that address]
     [34]  A86@  A12F  A33@  T54@  [make and plant order to store m{next}]
           A38@  G65@              [call subroutine to update "next"]
           A86@  S85@  G48@        [go to 48 if i < start]
           S2F   E48@              [go to 48 if i > start]
           TF  A82@  G52@          [make order to load tmp, and go to 52]
     [48]  TF  A86@  A12F  A81@    [make order to load m{next}]
     [52]  T53@                    [plant order to load tmp or m{next}]
     [53]  AF  [manufactured order; if i = start loads tmp, else loads m{next}]
     [54]  TF  [manufactured order; stores m{next}, using old value of "next"]
           A85@  S86@  G33@        [acc := start - next, loop back if < 0]
     [58]  TF  A85@  A2F  U85@     [start++]
           S84@  G8@               [loop until start = size]
     [64]  ZF                      [overwritten by return to caller]
    [Subroutine to execute next = (next % h) * w + next / h in C program]
     [65]  A3F  T80@               [set up return to caller]
           A86@  T4F  A11F  T5F    [set up parameters to divide "next" by "h"]
           A71@  G&                [call division subroutine]
         [In case anybody is following this in detail, note that "next" and "h" are
          stored in the address field, so we need to shift the quotient 1 left]
           H4F  V10F  L64F  L16F  A5F  LD  T86@  [compute RHS and store in "next"]
     [80]  ZF                      [overwritten by return to caller]
    [Constants]
     [81]  AF    [added to an address to make A order for that address]
     [82]  A83@  [order to load C variable "tmp"]
    [Variables; integers are stored in the address field for convenience.]
     [83]  PF    [C variable "tmp" (holds value of a matrix element)]
     [84]  PF    [size of matrix, width*height]
     [85]  PF    [C variable "start"]
     [86]  PF    [C variable "next"]
     [87]  PF    [C variable "i"]

 [Subroutine to print a matrix of 17-bit real numbers.]
     E25K  TM
     GKA3FT30@A13FT18@A12FA31@T14@S11FT36@S10FT37@O34@O35@TDAFT1FA16@
     GN
     PFA14@A2FT14@A37@A2FG10@O32@O33@A36@A2FG8@ZFAF@F&F!FMFPFPF

 [Library subroutine P1.
 Prints positive number in 0D to n places of decimals, where
 n is specified by 'P n F' pseudo-order after subroutine call.]
    E25K  TN
    GKA18@U17@S20@T5@H19@PFT5@VDUFOFFFSFL4FTDA5@A2FG6@EFU3FJFM1F

 [Integer division: number at 4F, divisor at 5F
 Returns remainder at 4F, quotient at 5F
 Working location 0D.  37 locations.]
    E25K T&
    GKA3FT34@A5FUFT35@A4FRDS35@G13@T1FA35@LDE4@T1FT5FA4FS35@G22@
    T4FA5FA36@T5FT1FAFS35@E34@T1FA35@RDT35@A5FLDT5FE15@EFPFPD

 [Main routine]
 [Given in condensed form, since it's the same as in part 1, except
  that the address of the transposed matrix is not required.]
  PKT250KGK#F@F&FP7FP4FP320FP2FTFP328FPFPFO@A5@A7@T23@H4@N3@L64FL32F
  T10@A9@A8@U9@TFA23@A2FT23@A10@A2FG19@A3@T10FA4@T11FA5@T12FA6@T13F
  A38@GMO1@O2@A42@GXA10FTFA11FT10FAFT11FA50@GMO@ZFE11ZPF
Output:
 .01 .02 .03 .04 .05 .06 .07
 .08 .09 .10 .11 .12 .13 .14
 .15 .16 .17 .18 .19 .20 .21
 .22 .23 .24 .25 .26 .27 .28

 .01 .08 .15 .22
 .02 .09 .16 .23
 .03 .10 .17 .24
 .04 .11 .18 .25
 .05 .12 .19 .26
 .06 .13 .20 .27
 .07 .14 .21 .28
 

Elixir

m = [[1,  1,  1,   1],
     [2,  4,  8,  16],
     [3,  9, 27,  81],
     [4, 16, 64, 256],
     [5, 25,125, 625]]

transpose = fn(m)-> List.zip(m) |> Enum.map(&Tuple.to_list(&1)) end

IO.inspect transpose.(m)
Output:
[[1, 2, 3, 4, 5], [1, 4, 9, 16, 25], [1, 8, 27, 64, 125], [1, 16, 81, 256, 625]]

ELLA

Sample originally from ftp://ftp.dra.hmg.gb/pub/ella (a now dead link) - Public release.

Code for matrix transpose hardware design verification:

MAC TRANSPOSE = ([INT n][INT m]TYPE t: matrix) -> [m][n]t:
  [INT i = 1..m] [INT j = 1..n] matrix[j][i].

Emacs Lisp

Library: cl-lib
(require 'cl-lib)

(defun transpose (m)
  (apply #'cl-mapcar #'list m))

;;test for transposition function
(transpose '((2 3 4 5) (3 5 6 9) (9 9 9 9)))
Output:
((2 3 9)
 (3 5 9)
 (4 6 9)
 (5 9 9))

Implementation using seq library:

(defun matrix-transposition (m)
  (apply #'seq-mapn (append (list #'list) m)) )

(let ((m '(( 2  0 -5 -1)
	       (-3 -2 -4  7)
	       (-1 -3  0 -6))))
  (message "%s" (matrix-transposition m)) )
Output:
((2 -3 -1) (0 -2 -3) (-5 -4 0) (-1 7 -6))

Erlang

A nice introduction http://langintro.com/erlang/article2/ which is much more explicit.

-module(transmatrix).
-export([trans/1,transL/1]).

% using built-ins hd = head, tl = tail

trans([[]|_]) -> [];
trans(M) ->
  [ lists:map(fun hd/1, M) | transpose( lists:map(fun tl/1, M) ) ].

% Purist version

transL( [ [Elem | Rest] | List] ) ->
    [ [Elem | [H || [H | _] <- List] ] |
      transL( [Rest | 
                      [ T || [_ | T] <- List ] ]
       ) ];
transL([ [] | List] ) -> transL(List);
transL([]) -> [].
Output:
 

2> transmatrix:transL( [ [1,2,3],[4,5,6],[7,8,9] ] ).
[[1,4,7],[2,5,8],[3,6,9]]

3> transmatrix:trans( [ [1,2,3],[4,5,6],[7,8,9] ] ).
[[1,4,7],[2,5,8],[3,6,9]]

Euphoria

function transpose(sequence in)
    sequence out
    out = repeat(repeat(0,length(in)),length(in[1]))
    for n = 1 to length(in) do
        for m = 1 to length(in[1]) do
            out[m][n] = in[n][m]
        end for
    end for
    return out
end function

sequence m
m = {
  {1,2,3,4},
  {5,6,7,8},
  {9,10,11,12}
}

? transpose(m)
Output:
 {
   {1,5,9},
   {2,6,10},
   {3,7,11},
   {4,8,12}
 }

Excel

Excel has a built-in TRANSPOSE function:

fx =TRANSPOSE(F2#)
A B C D E F G H I
1 Transposed Source matrix
2 1 5 9 1 2 3 4
3 2 6 10 5 6 7 8
4 3 7 11 9 10 11 12
5 4 8 12

F#

Very straightforward solution...

let transpose (mtx : _ [,]) = Array2D.init (mtx.GetLength 1) (mtx.GetLength 0) (fun x y -> mtx.[y,x])

Factor

flip can be used.

( scratchpad ) { { 1 2 3 } { 4 5 6 } } flip .
 { { 1 4 } { 2 5 } { 3 6 } }

Fermat

Matrix transpose is built in.

Array a[3,1]
[a]:=[(1,2,3)]
[b]:=Trans([a])
[a]
[b]
Output:
[[  1, `
    2, `
    3   ]]

[[  1,  2,  3  ]]

Forth

Works with: gforth version 0.7.9_20170308
S" fsl-util.fs" REQUIRED
S" fsl/dynmem.seq" REQUIRED
: F+! ( addr -- ) ( F: r -- )  DUP F@ F+ F! ;
: FSQR ( F: r1 -- r2 ) FDUP F* ;
S" fsl/gaussj.seq" REQUIRED

5 3 float matrix a{{
1e 2e 3e  4e 5e 6e  7e 8e 9e  10e 11e 12e  13e 14e 15e  5 3 a{{ }}fput
float dmatrix b{{

a{{ 5 3 & b{{ transpose
3 5 b{{ }}fprint

Fortran

In ISO Fortran 90 or later, use the TRANSPOSE intrinsic function:

integer, parameter   :: n = 3, m = 5
real, dimension(n,m) :: a = reshape( (/ (i,i=1,n*m) /), (/ n, m /) )
real, dimension(m,n) :: b

b = transpose(a)

do i = 1, n
    print *, a(i,:)
end do

do j = 1, m
    print *, b(j,:)
end do

In ANSI FORTRAN 77 with MIL-STD-1753 extensions or later, use nested structured DO loops:

REAL A(3,5), B(5,3)
DATA ((A(I,J),I=1,3),J=1,5) /1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15/

DO I = 1, 3
   DO J = 1, 5
      B(J,I) = A(I,J)
   END DO
END DO

In ANSI FORTRAN 66 or later, use nested labeled DO loops:

   REAL A(3,5), B(5,3)
   DATA ((A(I,J),I=1,3),J=1,5) /1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15/
   
   DO 10 I = 1, 3
      DO 20 J = 1, 5
         B(J,I) = A(I,J)
20    CONTINUE
10 CONTINUE

Explicit transposition via DO-loops was available from the start. Less obvious is that Fortran uses what is called "column major" order rather than "row major", which is to say that consecutive elements of the array are stored in memory with indices counting down the columns first, not along the rows. The above examples acknowledge this in the DATA statement with the ((A(row,col),row=1,3),col=1,5) which could therefore be replaced with just A, however one could use ((A(row,col),col=1,5),row=1,3) instead and the DATA values could be arranged so as to appear in the same layout as one expects for a matrix. Consider

      DIMENSION A(3,5),B(5,3),C(5,3)
      EQUIVALENCE (A,C)	!Occupy the same storage.
      DATA A/
     1     1, 2, 3, 4, 5,
     2     6, 7, 8, 9,10,
     3    11,12,13,14,15/	!Supplies values in storage order.

      WRITE (6,*) "Three rows of five values:"
      WRITE (6,1) A	!This shows values in storage order.
      WRITE (6,*) "...written as C(row,column):"
      WRITE (6,2) ((C(I,J),J = 1,3),I = 1,5)
      WRITE (6,*) "... written as A(row,column):"
      WRITE (6,1) ((A(I,J),J = 1,5),I = 1,3)

      WRITE (6,*)
      WRITE (6,*) "B = Transpose(A)"
      DO 10 I = 1,3
        DO 10 J = 1,5
   10     B(J,I) = A(I,J)

      WRITE (6,*) "Five rows of three values:"
      WRITE (6,2) B
      WRITE (6,*) "... written as B(row,column):"
      WRITE (6,2) ((B(I,J),J = 1,3),I = 1,5)

    1 FORMAT (5F6.1)	!Five values per line.
    2 FORMAT (3F6.1)	!Three values per line.
      END

Output:

 Three rows of five values:
   1.0   2.0   3.0   4.0   5.0
   6.0   7.0   8.0   9.0  10.0
  11.0  12.0  13.0  14.0  15.0
 ...written as C(row,column):
   1.0   6.0  11.0
   2.0   7.0  12.0
   3.0   8.0  13.0
   4.0   9.0  14.0
   5.0  10.0  15.0
 ... written as A(row,column):
   1.0   4.0   7.0  10.0  13.0
   2.0   5.0   8.0  11.0  14.0
   3.0   6.0   9.0  12.0  15.0

 B = Transpose(A)
 Five rows of three values:
   1.0   4.0   7.0
  10.0  13.0   2.0
   5.0   8.0  11.0
  14.0   3.0   6.0
   9.0  12.0  15.0
 ... written as B(row,column):
   1.0   2.0   3.0
   4.0   5.0   6.0
   7.0   8.0   9.0
  10.0  11.0  12.0
  13.0  14.0  15.0

Thus, the first output of A replicates the layout of the DATA statement, and the output of matrix C gives its transpose. But, the values in matrix A do not appear where they would be expected to appear in terms of (row,column) as applied to the layout of the DATA statement. Only after the transposition is this so. Put another way, the ordering of array values for statements just naming the matrix (the DATA statement, and the simple write statements of A and B) is the transpose of the (row,column) expectation for a matrix. All input and output statements for matrices should thus explicitly specify the index order, even for temporary debugging, lest confusion ensue.


FreeBASIC

Dim matriz(0 To 3, 0 To 4) As Integer = {{78,19,30,12,36},_
{49,10,65,42,50},_
{30,93,24,78,10},_
{39,68,27,64,29}}
Dim As Integer mtranspuesta(Lbound(matriz, 2) To Ubound(matriz, 2), Lbound(matriz, 1) To Ubound(matriz, 1))
Dim As Integer fila, columna

For fila = Lbound(matriz,1) To Ubound(matriz,1)
    For columna = Lbound(matriz,2) To Ubound(matriz,2)
        mtranspuesta(columna, fila) = matriz(fila, columna)
        Print ; matriz(fila,columna); " ";
    Next columna
    Print
Next fila
Print

For fila = Lbound(mtranspuesta,1) To Ubound(mtranspuesta,1)
    For columna = Lbound(mtranspuesta,2) To Ubound(mtranspuesta,2)
        Print ; mtranspuesta(fila,columna); " ";
    Next columna
    Print
Next fila
Sleep
Output:
 78  19  30  12  36
 49  10  65  42  50
 30  93  24  78  10
 39  68  27  64  29

 78  49  30  39
 19  10  93  68
 30  65  24  27
 12  42  78  64
 36  50  10  29


Frink

The built-in array method transpose transposes a 2-dimensional array.

a = [[1,2,3],
     [4,5,6],
     [7,8,9]]
joinln[a.transpose[]]

Fōrmulæ

Fōrmulæ programs are not textual, visualization/edition of programs is done showing/manipulating structures but not text. Moreover, there can be multiple visual representations of the same program. Even though it is possible to have textual representation —i.e. XML, JSON— they are intended for storage and transfer purposes more than visualization and edition.

Programs in Fōrmulæ are created/edited online in its website.

In this page you can see and run the program(s) related to this task and their results. You can also change either the programs or the parameters they are called with, for experimentation, but remember that these programs were created with the main purpose of showing a clear solution of the task, and they generally lack any kind of validation.

Solution

Matrix transposition is an intrsinec operation in Fōrmulæ, through the Transpose expression:

 

 

However, a matrix transposition can be coded:

 

 

 

GAP

originalMatrix := [[1, 1, 1, 1],
                   [2, 4, 8, 16],
                   [3, 9, 27, 81],
                   [4, 16, 64, 256],
                   [5, 25, 125, 625]];
transposedMatrix := TransposedMat(originalMatrix);

Go

Library gonum/mat

package main

import (
    "fmt"

    "gonum.org/v1/gonum/mat"
)

func main() {
    m := mat.NewDense(2, 3, []float64{
        1, 2, 3,
        4, 5, 6,
    })
    fmt.Println(mat.Formatted(m))
    fmt.Println()
    fmt.Println(mat.Formatted(m.T()))
}
Output:
⎡1  2  3⎤
⎣4  5  6⎦

⎡1  4⎤
⎢2  5⎥
⎣3  6⎦

Library go.matrix

package main

import (
    "fmt"

    mat "github.com/skelterjohn/go.matrix"
)

func main() {
    m := mat.MakeDenseMatrixStacked([][]float64{
        {1, 2, 3},
        {4, 5, 6},
    })
    fmt.Println("original:")
    fmt.Println(m)
    m = m.Transpose()
    fmt.Println("transpose:")
    fmt.Println(m)
}
Output:
original:
{1, 2, 3,
 4, 5, 6}
transpose:
{1, 4,
 2, 5,
 3, 6}

2D representation

Go arrays and slices are only one-dimensional. The obvious way to represent two-dimensional arrays is with a slice of slices:

package main

import "fmt"

type row []float64
type matrix []row

func main() {
    m := matrix{
        {1, 2, 3},
        {4, 5, 6},
    }
    printMatrix(m)
    t := transpose(m)
    printMatrix(t)
}

func printMatrix(m matrix) {
    for _, s := range m {
        fmt.Println(s)
    }
}

func transpose(m matrix) matrix {
    r := make(matrix, len(m[0]))
    for x, _ := range r {
        r[x] = make(row, len(m))
    }
    for y, s := range m {
        for x, e := range s {
            r[x][y] = e
        }
    }
    return r
}
Output:
[1 2 3]
[4 5 6]
[1 4]
[2 5]
[3 6]

Flat representation

Slices of slices turn out to have disadvantages. It is possible to construct ill-formed matricies with a different number of elements on different rows, for example. They require multiple allocations, and the compiler must generate complex address calculations to index elements.

A flat element representation with a stride is almost always better.

package main

import "fmt"

type matrix struct {
    ele    []float64
    stride int
}

// construct new matrix from slice of slices
func matrixFromRows(rows [][]float64) *matrix {
    if len(rows) == 0 {
        return &matrix{nil, 0}
    }
    m := &matrix{make([]float64, len(rows)*len(rows[0])), len(rows[0])}
    for rx, row := range rows {
        copy(m.ele[rx*m.stride:(rx+1)*m.stride], row)
    }
    return m
}

func main() {
    m := matrixFromRows([][]float64{
        {1, 2, 3},
        {4, 5, 6},
    })
    m.print("original:")
    m.transpose().print("transpose:")
}

func (m *matrix) print(heading string) {
    if heading > "" {
        fmt.Print("\n", heading, "\n")
    }
    for e := 0; e < len(m.ele); e += m.stride {
        fmt.Println(m.ele[e : e+m.stride])
    }
}

func (m *matrix) transpose() *matrix {
    r := &matrix{make([]float64, len(m.ele)), len(m.ele) / m.stride}
    rx := 0
    for _, e := range m.ele {
        r.ele[rx] = e
        rx += r.stride
        if rx >= len(r.ele) {
            rx -= len(r.ele) - 1
        }
    }
    return r
}
Output:
original:
[1 2 3]
[4 5 6]

transpose:
[1 4]
[2 5]
[3 6]

Transpose in place

Translation of: C

Note representation is "flat," as above, but without the fluff of constructing from rows.

package main

import "fmt"

type matrix struct {
    stride int
    ele    []float64
}

func main() {
    m := matrix{3, []float64{
        1, 2, 3,
        4, 5, 6,
    }}
    m.print("original:")
    m.transposeInPlace()
    m.print("transpose:")
}

func (m *matrix) print(heading string) {
    if heading > "" {
        fmt.Print("\n", heading, "\n")
    }
    for e := 0; e < len(m.ele); e += m.stride {
        fmt.Println(m.ele[e : e+m.stride])
    }
}

func (m *matrix) transposeInPlace() {
    h := len(m.ele) / m.stride
    for start := range m.ele {
        next := start
        i := 0
        for {
            i++
            next = (next%h)*m.stride + next/h
            if next <= start {
                break
            }
        }
        if next < start || i == 1 {
            continue
        }

        next = start
        tmp := m.ele[next]
        for {
            i = (next%h)*m.stride + next/h
            if i == start {
                m.ele[next] = tmp
            } else {
                m.ele[next] = m.ele[i]
            }
            next = i
            if next <= start {
                break
            }
        }
    }
    m.stride = h
}

Output same as above.

Groovy

The Groovy extensions to the List class provides a transpose method:

def matrix = [ [ 1, 2, 3, 4 ],
               [ 5, 6, 7, 8 ] ]

matrix.each { println it }
println()
def transpose = matrix.transpose()

transpose.each { println it }
Output:
[1, 2, 3, 4]
[5, 6, 7, 8]

[1, 5]
[2, 6]
[3, 7]
[4, 8]

Haskell

For matrices represented as lists, there's transpose:

*Main> transpose [[1,2],[3,4],[5,6]]
[[1,3,5],[2,4,6]]

For matrices in arrays, one can use ixmap:

import Data.Array

swap (x,y) = (y,x)

transpArray :: (Ix a, Ix b) => Array (a,b) e -> Array (b,a) e
transpArray a = ixmap (swap l, swap u) swap a where 
  (l,u) = bounds a

Using zipWith assuming a matrix is a list of row lists:

tpose [ms] = [[m] | m <- ms]
tpose (ms:mss) = zipWith (:) ms (tpose mss)
Output:
tpose [[1,2,3],[4,5,6],[7,8,9]]
[[1,4,7],[2,5,8],[3,6,9]]

or, in terms of Data.Matrix:

import Data.Matrix

main :: IO ()
main = print matrix >> print (transpose matrix)
  where
    matrix = fromList 3 4 [1 ..]
Output:
┌             ┐
│  1  2  3  4 │
│  5  6  7  8 │
│  9 10 11 12 │
└             ┘
┌          ┐
│  1  5  9 │
│  2  6 10 │
│  3  7 11 │
│  4  8 12 │
└          ┘

With Numeric.LinearAlgebra

import Numeric.LinearAlgebra

a :: Matrix I
a = (3><2) 
  [1,2
  ,3,4
  ,5,6]

main = do
  print $ a
  print $ tr a
Output:
(3><2)
 [ 1, 2
 , 3, 4
 , 5, 6 ]
(2><3)
 [ 1, 3, 5
 , 2, 4, 6 ]

Haxe

class Matrix {
    static function main() {
        var m = [ [1,  1,   1,   1],
                  [2,  4,   8,  16],
                  [3,  9,  27,  81],
                  [4, 16,  64, 256],
                  [5, 25, 125, 625] ];
        var t = [ for (i in 0...m[0].length)
                      [ for (j in 0...m.length) 0 ] ];
        for(i in 0...m.length)
            for(j in 0...m[0].length)
                t[j][i] = m[i][j];

        for(aa in [m, t])
            for(a in aa) Sys.println(a);
    }
}
Output:
[1,1,1,1]
[2,4,8,16]
[3,9,27,81]
[4,16,64,256]
[5,25,125,625]
[1,2,3,4,5]
[1,4,9,16,25]
[1,8,27,64,125]
[1,16,81,256,625]

HicEst

REAL :: mtx(2, 4)

mtx = 1.1 * $
WRITE() mtx

SOLVE(Matrix=mtx, Transpose=mtx)
WRITE() mtx
Output:
1.1 2.2 3.3 4.4 
5.5 6.6 7.7 8.8 

1.1 5.5 
2.2 6.6 
3.3 7.7 
4.4 8.8 

Hope

uses lists;
dec transpose : list (list alpha) -> list (list alpha);
--- transpose ([]::_) <= [];
--- transpose n <= map head n :: transpose (map tail n);

Icon and Unicon

procedure transpose_matrix (matrix)
  result := []
  # for each column
  every (i := 1 to *matrix[1]) do {
    col := []
    # extract the number in each row for that column
    every (row := !matrix) do put (col, row[i]) 
    # and push that column as a row in the result matrix
    put (result, col)
  }
  return result
end

procedure print_matrix (matrix)
  every (row := !matrix) do {
    every writes (!row || " ")
    write ()
  }
end

procedure main ()
  matrix := [[1,2,3],[4,5,6]]
  write ("Start:")
  print_matrix (matrix)
  transposed := transpose_matrix (matrix)
  write ("Transposed:")
  print_matrix (transposed)
end
Output:
Start:
1 2 3 
4 5 6 
Transposed:
1 4 
2 5 
3 6

IDL

Standard IDL function transpose()

m=[[1,1,1,1],[2, 4, 8, 16],[3, 9,27, 81],[5, 25,125, 625]]
print,transpose(m)

Idris

Idris> transpose [[1,2],[3,4],[5,6]]
[[1, 3, 5], [2, 4, 6]] : List (List Integer)

Insitux

(var transpose2d @(... map vec))

(transpose2d [[1 1 1 1] [2 4 8 16] [3 9 27 81] [4 16 64 256] [5 25 125 625]])
Output:
[[1 2 3 4 5] [1 4 9 16 25] [1 8 27 64 125] [1 16 81 256 625]]

J

Solution:
Transpose is the monadic primary verb |:

Example:

   ]matrix=: (^/ }:) >:i.5    NB. make and show example matrix
1  1   1   1
2  4   8  16
3  9  27  81
4 16  64 256
5 25 125 625
   |: matrix
1  2  3   4   5
1  4  9  16  25
1  8 27  64 125
1 16 81 256 625

As an aside, note that . and : are token forming suffixes (if they immediately follow a token forming character, they are a part of the token). This usage is in analogy to the use of diacritics in many languages. (If you want to use  : or . as tokens by themselves you must precede them with a space - beware though that wiki rendering software may sometimes elide the preceding space in <code> .</code> contexts.)

Java

import java.util.Arrays;
public class Transpose{
       public static void main(String[] args){
               double[][] m = {{1, 1, 1, 1},
                               {2, 4, 8, 16},
                               {3, 9, 27, 81},
                               {4, 16, 64, 256},
                               {5, 25, 125, 625}};
               double[][] ans = new double[m[0].length][m.length];
               for(int rows = 0; rows < m.length; rows++){
                       for(int cols = 0; cols < m[0].length; cols++){
                               ans[cols][rows] = m[rows][cols];
                       }
               }
               for(double[] i:ans){//2D arrays are arrays of arrays
                       System.out.println(Arrays.toString(i));
               }
       }
}

JavaScript

ES5

Works with: SpiderMonkey

for the print() function

function Matrix(ary) {
    this.mtx = ary
    this.height = ary.length;
    this.width = ary[0].length;
}

Matrix.prototype.toString = function() {
    var s = []
    for (var i = 0; i < this.mtx.length; i++) 
        s.push( this.mtx[i].join(",") );
    return s.join("\n");
}

// returns a new matrix
Matrix.prototype.transpose = function() {
    var transposed = [];
    for (var i = 0; i < this.width; i++) {
        transposed[i] = [];
        for (var j = 0; j < this.height; j++) {
            transposed[i][j] = this.mtx[j][i];
        }
    }
    return new Matrix(transposed);
}

var m = new Matrix([[1,1,1,1],[2,4,8,16],[3,9,27,81],[4,16,64,256],[5,25,125,625]]);
print(m);
print();
print(m.transpose());

produces

1,1,1,1
2,4,8,16
3,9,27,81
4,16,64,256
5,25,125,625

1,2,3,4,5
1,4,9,16,25
1,8,27,64,125
1,16,81,256,625


Or, as a functional expression (rather than an imperative procedure):

(function () {
    'use strict';

    function transpose(lst) {
        return lst[0].map(function (_, iCol) {
            return lst.map(function (row) {
                return row[iCol];
            })
        });
    }
    
    return transpose(
        [[1, 2, 3], [4, 5, 6], [7, 8, 9], [10, 11, 12]]
    );

})();
Output:
[[1, 4, 7, 10], [2, 5, 8, 11], [3, 6, 9, 12]]

ES6

(() => {
    "use strict";

    // transpose :: [[a]] -> [[a]]
    const transpose = xs =>
        0 < xs.length ? (
            xs[0].map(
                (_, iCol) => xs.map(
                    row => row[iCol]
                )
            )
        ) : [];


    // ---------------------- TEST -----------------------
    const main = () =>
        JSON.stringify(
            transpose([
                [1, 2, 3],
                [4, 5, 6],
                [7, 8, 9]
            ])
        );


    // MAIN ---
    return main();
})();
Output:
[[1,4,7],[2,5,8],[3,6,9]]

Joy

For matrices represented as lists, there's transpose, defined in seqlib like this:

DEFINE transpose == [[null] [true] [[null] some] ifte]
[pop []]
[[[first] map] [[rest] map] cleave]
[cons]
linrec.

jq

Works with: jq version 1.4

Recent versions of jq include a more general "transpose" that can be used to transpose jagged matrices.

The following definition of transpose/0 expects its input to be a non-empty array, each element of which should be an array of the same size. The result is an array that represents the transposition of the input.

def transpose:
  if (.[0] | length) == 0 then []
  else [map(.[0])] + (map(.[1:]) | transpose)
  end ;

Examples

[[], []] | transpose
# => []
[[1], [3]] | transpose
# => 1,3
[[1,2], [3,4]] | transpose
# => [[1,3],[2,4]]

Jsish

From the Javascript Matrix entries.

First a module, shared by the Transposition, Multiplication and Exponentiation tasks.

/* Matrix transposition, multiplication, identity, and exponentiation, in Jsish */
function Matrix(ary) {
    this.mtx = ary;
    this.height = ary.length;
    this.width = ary[0].length;
}
 
Matrix.prototype.toString = function() {
    var s = [];
    for (var i = 0; i < this.mtx.length; i++) s.push(this.mtx[i].join(","));
    return s.join("\n");
};
 
// returns a transposed matrix
Matrix.prototype.transpose = function() {
    var transposed = [];
    for (var i = 0; i < this.width; i++) {
        transposed[i] = [];
        for (var j = 0; j < this.height; j++) transposed[i][j] = this.mtx[j][i];
    }
    return new Matrix(transposed);
};

// returns a matrix as the product of two others
Matrix.prototype.mult = function(other) {
    if (this.width != other.height) throw "error: incompatible sizes";
 
    var result = [];
    for (var i = 0; i < this.height; i++) {
        result[i] = [];
        for (var j = 0; j < other.width; j++) {
            var sum = 0;
            for (var k = 0; k < this.width; k++) sum += this.mtx[i][k] * other.mtx[k][j];
            result[i][j] = sum;
        }
    }
    return new Matrix(result);
};

// IdentityMatrix is a "subclass" of Matrix
function IdentityMatrix(n) {
    this.height = n;
    this.width = n;
    this.mtx = [];
    for (var i = 0; i < n; i++) {
        this.mtx[i] = [];
        for (var j = 0; j < n; j++) this.mtx[i][j] = (i == j ? 1 : 0);
    }
}
IdentityMatrix.prototype = Matrix.prototype;

// the Matrix exponentiation function
Matrix.prototype.exp = function(n) {
    var result = new IdentityMatrix(this.height);
    for (var i = 1; i <= n; i++) result = result.mult(this);
    return result;
};

provide('Matrix', '0.60');

Then a unitTest of the transposition.

/* Matrix transposition, in Jsish */
require('Matrix');

if (Interp.conf('unitTest')) {
    var m = new Matrix([[1,1,1,1],[2,4,8,16],[3,9,27,81],[4,16,64,256],[5,25,125,625]]);
;    m;
;    m.transpose();
}

/*
=!EXPECTSTART!=
m ==> { height:5, mtx:[ [ 1, 1, 1, 1 ], [ 2, 4, 8, 16 ], [ 3, 9, 27, 81 ], [ 4, 16, 64, 256 ], [ 5, 25, 125, 625 ] ], width:4 }
m.transpose() ==> { height:4, mtx:[ [ 1, 2, 3, 4, 5 ], [ 1, 4, 9, 16, 25 ], [ 1, 8, 27, 64, 125 ], [ 1, 16, 81, 256, 625 ] ], width:5 }
=!EXPECTEND!=
*/
Output:
prompt$ jsish -u matrixTranspose.jsi
[PASS] matrixTranspose.jsi

Julia

The transposition is obtained by quoting the matrix.

julia> [1 2 3 ; 4 5 6]  # a 2x3 matrix
2x3 Array{Int64,2}:
 1  2  3
 4  5  6

julia> [1 2 3 ; 4 5 6]'  # note the quote
3x2 LinearAlgebra.Adjoint{Int64,Array{Int64,2}}:
 1  4
 2  5
 3  6

If you do not want change the type, convert the result back to Array{Int64,2}.

K

Transpose is the monadic verb +

  {x^\:-1_ x}1+!:5
(1 1 1 1.0
 2 4 8 16.0
 3 9 27 81.0
 4 16 64 256.0
 5 25 125 625.0)

  +{x^\:-1_ x}1+!:5
(1 2 3 4 5.0
 1 4 9 16 25.0
 1 8 27 64 125.0
 1 16 81 256 625.0)

Klong

Transpose is the monadic verb +

    [5 5]:^!25
[[0 1 2 3 4]
 [5 6 7 8 9]
 [10 11 12 13 14]
 [15 16 17 18 19]
 [20 21 22 23 24]]

    +[5 5]:^!25
[[0 5 10 15 20]
 [1 6 11 16 21]
 [2 7 12 17 22]
 [3 8 13 18 23]
 [4 9 14 19 24]]

Kotlin

// version 1.1.3

typealias Vector = DoubleArray
typealias Matrix = Array<Vector>

fun Matrix.transpose(): Matrix {
    val rows = this.size
    val cols = this[0].size
    val trans = Matrix(cols) { Vector(rows) }
    for (i in 0 until cols) {
        for (j in 0 until rows) trans[i][j] = this[j][i]
    }
    return trans
}

// Alternate version
typealias Matrix<T> = List<List<T>>
fun <T> Matrix<T>.transpose(): Matrix<T> {
    return (0 until this[0].size).map { x ->
        (this.indices).map { y ->
            this[y][x]
        }
    }
}


Lambdatalk

{require lib_matrix}

{M.disp 
 {M.transp
[[1,  1,  1,   1],
 [2,  4,  8,  16],
 [3,  9, 27,  81],
 [4, 16, 64, 256],
 [5, 25,125, 625]]
}}
-> 
[[1,2,3,4,5],
[1,4,9,16,25],
[1,8,27,64,125],
[1,16,81,256,625]]

Lang5

12 iota [3 4] reshape 1 + dup .
1 transpose .
Output:
[
  [    1     2     3     4  ]
  [    5     6     7     8  ]
  [    9    10    11    12  ]
][
  [    1     5     9  ]
  [    2     6    10  ]
  [    3     7    11  ]
  [    4     8    12  ]
]

LFE

(defun transpose (matrix)
  (transpose matrix '()))

(defun transpose (matrix acc)
  (cond
    ((lists:any
        (lambda (x) (== x '()))
        matrix)
     acc)
    ('true
      (let ((heads (lists:map #'car/1 matrix))
            (tails (lists:map #'cdr/1 matrix)))
        (transpose tails (++ acc `(,heads)))))))

Usage in the LFE REPL:

> (transpose '((1  2  3)
               (4  5  6)
               (7  8  9)
               (10 11 12)
               (13 14 15)
               (16 17 18)))
((1 4 7 10 13 16) (2 5 8 11 14 17) (3 6 9 12 15 18))
>

Liberty BASIC

There is no native matrix capability. A set of functions is available at http://www.diga.me.uk/RCMatrixFuncs.bas implementing matrices of arbitrary dimension in a string format.

MatrixC$ ="4, 3,          0, 0.10, 0.20, 0.30,       0.40, 0.50, 0.60, 0.70,      0.80, 0.90, 1.00, 1.10"

print "Transpose of matrix"
call DisplayMatrix MatrixC$
print "         ="
MatrixT$ =MatrixTranspose$( MatrixC$)
call DisplayMatrix MatrixT$
Output:
Transpose of matrix
| 0.00000 0.10000 0.20000 0.30000 |
| 0.40000 0.50000 0.60000 0.70000 |
| 0.80000 0.90000 1.00000 1.10000 |

=
| 0.00000 0.40000 0.80000 |
| 0.10000 0.50000 0.90000 |
| 0.20000 0.60000 1.00000 |
| 0.30000 0.70000 1.10000 |

Lua

function Transpose( m )
    local res = {}
    
    for i = 1, #m[1] do
        res[i] = {}
        for j = 1, #m do
            res[i][j] = m[j][i]
        end
    end
    
    return res
end

-- a test for Transpose(m)
mat = { { 1, 2, 3 }, { 4, 5, 6 } }
erg = Transpose( mat )
for i = 1, #erg do
    for j = 1, #erg[1] do
        io.write( erg[i][j] )
        io.write( "  " )
    end
    io.write( "\n" )
end

Using apply map list

function map(f, a)
  local b = {}
  for k,v in ipairs(a) do b[k] = f(v) end
  return b
end

function mapn(f, ...)
  local c = {}
  local k = 1
  local aarg = {...}
  local n = #aarg
  while true do
    local a = map(function(b) return b[k] end, aarg)
    if #a < n then return c end
    c[k] = f(unpack(a))
    k = k + 1
  end
end

function apply(f1, f2, a)
 return f1(f2, unpack(a))
end

xy = {{1,2,3,4},{1,2,3,4},{1,2,3,4}}
yx = apply(mapn, function(...) return {...} end, xy)
print(table.concat(map(function(a) return table.concat(a,",") end, xy), "\n"),"\n")
print(table.concat(map(function(a) return table.concat(a,",") end, yx), "\n"))

--Edit: table.getn() deprecated, using # instead

Maple

The Transpose function in Maple's LinearAlgebra package computes this. The computation can also be accomplished by raising the Matrix to the %T power. Similarly for HermitianTranspose and the %H power.

M := <<2,3>|<3,4>|<5,6>>;

M^%T;

with(LinearAlgebra):
Transpose(M);
Output:
                                    [2  3  5]
                               M := [       ]
                                    [3  4  6]

                                   [2  3]
                                   [    ]
                                   [3  4]
                                   [    ]
                                   [5  6]

                                   [2  3]
                                   [    ]
                                   [3  4]
                                   [    ]
                                   [5  6]

Mathematica /Wolfram Language

originalMatrix = {{1, 1, 1, 1},
                  {2, 4, 8, 16},
                  {3, 9, 27, 81},
                  {4, 16, 64, 256},
                  {5, 25, 125, 625}}
transposedMatrix = Transpose[originalMatrix]

MATLAB

Matlab contains two built-in methods of transposing a matrix: by using the transpose() function, or by using the .' operator. The ' operator yields the complex conjugate transpose.

>> transpose([1 2;3 4])

ans =

     1     3
     2     4

>> [1 2;3 4].'

ans =

     1     3
     2     4

But, you can, obviously, do the transposition of a matrix without a built-in method, in this case, the code can be this hereafter code:

B=size(A);   %In this code, we assume that a previous matrix "A" has already been inputted.
for j=1:B(1)
    for i=1:B(2)
        C(i,j)=A(j,i);
    end      %The transposed A-matrix should be C 
end

Transposing nested cells using apply map list

xy = {{1,2,3,4},{1,2,3,4},{1,2,3,4}}
yx = feval(@(x) cellfun(@(varargin)[varargin],x{:},'un',0), xy)

Maxima

originalMatrix : matrix([1, 1, 1, 1],
                        [2, 4, 8, 16],
                        [3, 9, 27, 81],
                        [4, 16, 64, 256],
                        [5, 25, 125, 625]);
transposedMatrix : transpose(originalMatrix);

MAXScript

Uses the built in transpose() function

m = bigMatrix 5 4
for i in 1 to 5 do for j in 1 to 4 do m[i][j] = pow i j
m = transpose m

Nial

make an array

|a := 2 3 reshape count 6
=1 2 3
=4 5 6

transpose it

|transpose a
=1 4
=2 5
=3 6

Nim

For statically sized arrays:

proc transpose[X, Y; T](s: array[Y, array[X, T]]): array[X, array[Y, T]] =
  for i in low(X)..high(X):
    for j in low(Y)..high(Y):
      result[i][j] = s[j][i]

let b = [[ 0, 1, 2, 3, 4],
         [ 5, 6, 7, 8, 9],
         [ 1, 0, 0, 0,42]]
let c = transpose(b)
for r in c:
  for i in r:
    stdout.write i, " "
  echo ""
Output:
 0  5  1 
 1  6  0 
 2  7  0 
 3  8  0 
 4  9 42 

For dynamically sized seqs:

proc transpose[T](s: seq[seq[T]]): seq[seq[T]] =
  result = newSeq[seq[T]](s[0].len)
  for i in 0 .. s[0].high:
    result[i] = newSeq[T](s.len)
    for j in 0 .. s.high:
      result[i][j] = s[j][i]
 
let a = @[@[ 0, 1, 2, 3,  4],
          @[ 5, 6, 7, 8,  9],
          @[ 1, 0, 0, 0, 42]]
echo transpose(a)
Output:
@[@[0, 5, 1], @[1, 6, 0], @[2, 7, 0], @[3, 8, 0], @[4, 9, 42]]

Nu

Works with: Nushell version 0.97.1
def 'matrix transpose' [] {
  each { into record } | values
}

[[1 5 9] [2 6 10] [3 7 11] [4 8 12]] | matrix transpose | to nuon
Output:
[[1, 2, 3, 4], [5, 6, 7, 8], [9, 10, 11, 12]]

Objeck

bundle Default {
  class Transpose {
    function : Main(args : String[]) ~ Nil {
      input := [[1, 1, 1, 1]
        [2, 4, 8, 16]
        [3, 9, 27, 81]
        [4, 16, 64, 256]
        [5, 25, 125, 625]];
      dim := input->Size();

      output := Int->New[dim[0],dim[1]];
      for(i := 0; i < dim[0]; i+=1;) {
        for(j := 0; j < dim[1]; j+=1;) {
          output[i,j] := input[i,j];
        };
      };

      Print(output);
    }

    function : Print(matrix : Int[,]) ~ Nil {
      dim := matrix->Size();
      for(i := 0; i < dim[0]; i+=1;) {
        for(j := 0; j < dim[1]; j+=1;) {
          IO.Console->Print(matrix[i,j])->Print('\t');
        };
        '\n'->Print();
      };
    }
  }
}
Output:
1	2	3	4	5	
1	4	9	16	25	
1	8	27	64	125	
1	16	81	256	625

OCaml

Matrices can be represented in OCaml as a type 'a array array, or using the module Bigarray. The implementation below uses a bigarray:

open Bigarray

let transpose b =
  let dim1 = Array2.dim1 b
  and dim2 = Array2.dim2 b in
  let kind = Array2.kind b
  and layout = Array2.layout b in
  let b' = Array2.create kind layout dim2 dim1 in
  for i=0 to pred dim1 do
    for j=0 to pred dim2 do
      b'.{j,i} <- b.{i,j}
    done;
  done;
  (b')
;;

let array2_display print newline b =
  for i=0 to Array2.dim1 b - 1 do
    for j=0 to Array2.dim2 b - 1 do
      print b.{i,j}
    done;
    newline();
  done;
;;

let a = Array2.of_array int c_layout [|
  [| 1; 2; 3; 4 |];
  [| 5; 6; 7; 8 |];
|]
;;

array2_display (Printf.printf " %d") print_newline (transpose a) ;;
Output:
 1 5
 2 6
 3 7
 4 8

A version for lists:

let rec transpose m =
  assert (m <> []);
  if List.mem [] m then
    []
  else
    List.map List.hd m :: transpose (List.map List.tl m)

Example:

# transpose [[1;2;3;4];
             [5;6;7;8]];;
- : int list list = [[1; 5]; [2; 6]; [3; 7]; [4; 8]]

Octave

a = [ 1, 1, 1, 1 ;
      2, 4, 8, 16 ;
      3, 9, 27, 81 ;
      4, 16, 64, 256 ;
      5, 25, 125, 625 ];
tranposed = a.'; % tranpose
ctransp = a'; % conjugate transpose

OxygenBasic

function Transpose(double *A,*B, sys nx,ny)
'==========================================
  sys x,y
  indexbase 0
  for x=0 to <nx
    for y=0 to <ny
      B[y*nx+x]=A[x*ny+y]
    next
  next
end function

function MatrixShow(double*A, sys nx,ny) as string
'=================================================
  sys x,y
  indexbase 0
  string pr="",tab=chr(9),cr=chr(13)+chr(10)
  for y=0 to <ny
    for x=0 to <nx
      pr+=tab A[x*ny+y]
    next
    pr+=cr
  next
  return pr
end function

'====
'DEMO
'====

double A[5*4],B[4*5]
'columns x
'rows    y

A <= 'y minor, x major
11,12,13,14,15,
21,22,23,24,25,
31,32,33,34,35,
41,42,43,44,45

print MatrixShow A,5,4
Transpose        A,B,5,4
print MatrixShow B,4,5

PARI/GP

The GP function for matrix (or vector) transpose is mattranspose, but it is usually invoked with a tilde:

M~

In PARI the function is

gtrans(M)

though shallowtrans is also available when deep copying is not desired.

Pascal

Program Transpose;

const
  A: array[1..3,1..5] of integer = (( 1,  2,  3,  4,  5), 
                                    ( 6,  7,  8,  9, 10),
				    (11, 12, 13, 14, 15)
				   );
var
  B: array[1..5,1..3] of integer;
  i, j: integer;

begin
  for i := low(A) to high(A) do
    for j := low(A[1]) to high(A[1]) do
      B[j,i] := A[i,j];

  writeln ('A:');
  for i := low(A) to high(A) do
  begin
    for j := low(A[1]) to high(A[1]) do
      write (A[i,j]:3);
    writeln;
  end;

  writeln ('B:');
  for i := low(B) to high(B) do
  begin
    for j := low(B[1]) to high(B[1]) do
      write (B[i,j]:3);
    writeln;
  end;
end.
Output:
% ./Transpose
A:
  1  2  3  4  5
  6  7  8  9 10
 11 12 13 14 15
B:
  1  6 11
  2  7 12
  3  8 13
  4  9 14
  5 10 15

PascalABC.NET

uses NumLibABC;

begin
  var A := new Matrix(4, 3, 
          1, 2, 3, 
          4, 5, 6, 
          7, 8, 9, 
          10, 11, 12);
  'Original:'.Println;
  A.Println(3, 0);
  'Transposed:'.Println;
  A.Transpose.Println(3, 0);
end.
Output:
Original:
  1  2  3
  4  5  6
  7  8  9
 10 11 12
Transposed:
  1  4  7 10
  2  5  8 11
  3  6  9 12

Perl

use Math::Matrix;

$m = Math::Matrix->new(
  [1, 1, 1, 1],
  [2, 4, 8, 16],
  [3, 9, 27, 81],
  [4, 16, 64, 256],
  [5, 25, 125, 625],
);

$m->transpose->print;
Output:
 1.00000    2.00000    3.00000    4.00000    5.00000 
 1.00000    4.00000    9.00000   16.00000   25.00000 
 1.00000    8.00000   27.00000   64.00000  125.00000 
 1.00000   16.00000   81.00000  256.00000  625.00000

Manually:

my @m = (
  [1, 1, 1, 1],
  [2, 4, 8, 16],
  [3, 9, 27, 81],
  [4, 16, 64, 256],
  [5, 25, 125, 625],
);

my @transposed;
foreach my $j (0..$#{$m[0]}) {
  push(@transposed, [map $_->[$j], @m]);
}

Phix

with javascript_semantics
function matrix_transpose(sequence mat)
    integer rows = length(mat),
            cols = length(mat[1])
    sequence res = repeat(repeat(0,rows),cols)
    for r=1 to rows do
        for c=1 to cols do
            res[c][r] = mat[r][c]
        end for
    end for
    return res
end function

PHP

Up to PHP version 5.6

function transpose($m) {
  if (count($m) == 0) // special case: empty matrix
    return array();
  else if (count($m) == 1) // special case: row matrix
    return array_chunk($m[0], 1);

  // array_map(NULL, m[0], m[1], ..)
  array_unshift($m, NULL); // the original matrix is not modified because it was passed by value
  return call_user_func_array('array_map', $m);
}


Starting with PHP 5.6

function transpose($m) { 
    return count($m) == 0 ? $m : (count($m) == 1 ? array_chunk($m[0], 1) : array_map(null, ...$m)); 
}

Picat

Picat has a built-in function transpose/1 (in the util module).

import util.

go =>
  M = [[0.0, 0.1, 0.2, 0.3],
       [0.4, 0.5, 0.6, 0.7],
       [0.8, 0.9, 1.0, 1.1]],
  print_matrix(M),

  M2 = [[a,b,c,d,e],
        [f,g,h,i,j],
        [k,l,m,n,o],
        [p,q,r,s,t],
        [u,v,w,z,y]],
  print_matrix(M2),

  M3 = make_matrix(1..24,8),
  print_matrix(M3),
  nl.


%
% Print original matrix and its transpose
%
print_matrix(M) =>
  println("Matrix:"),
  foreach(Row in M) println(Row) end,
  println("\nTransposed:"),
  foreach(Row in M.transpose()) println(Row) end,
  nl.

%
% Make a matrix of list L with Rows rows 
% (and L.length div Rows columns)
%
make_matrix(L,Rows) = M =>
  M = [],
  Cols = L.length div Rows,
  foreach(I in 1..Rows)
     NewRow = new_list(Cols),
     foreach(J in 1..Cols)
       NewRow[J] := L[ (I-1)*Cols + J]
     end,
     M := M ++ [NewRow]
  end.
Output:
Matrix:
[0.0,0.1,0.2,0.3]
[0.4,0.5,0.6,0.7]
[0.8,0.9,1.0,1.1]

Transposed:
[0.0,0.4,0.8]
[0.1,0.5,0.9]
[0.2,0.6,1.0]
[0.3,0.7,1.1]

Matrix:
abcde
fghij
klmno
pqrst
uvwzy

Transposed:
afkpu
bglqv
chmrw
dinsz
ejoty

Matrix:
[1,2,3]
[4,5,6]
[7,8,9]
[10,11,12]
[13,14,15]
[16,17,18]
[19,20,21]
[22,23,24]

Transposed:
[1,4,7,10,13,16,19,22]
[2,5,8,11,14,17,20,23]
[3,6,9,12,15,18,21,24]

PicoLisp

(de matTrans (Mat)
   (apply mapcar Mat list) )

(matTrans '((1 2 3) (4 5 6)))
Output:
-> ((1 4) (2 5) (3 6))

PL/I

/* The short method: */
declare A(m, n) float, B (n,m) float defined (A(2sub, 1sub));
/* Any reference to B gives the transpose of matrix A. */

Traditional method:

/* Transpose matrix A, result at B. */
transpose: procedure (a, b);
   declare (a, b) (*,*) float controlled;
   declare (m, n) fixed binary;

   if allocation(b) > 0 then free b;

   m = hbound(a,1); n = hbound(a,2);

   allocate b(n,m);

   do i = 1 to m;
      b(*,i) = a(i,*);
   end;
end transpose;

Pop11

define transpose(m) -> res;
    lvars bl = boundslist(m);
    if length(bl) /= 4 then
        throw([need_2d_array ^a])
    endif;
    lvars i, i0 = bl(1), i1 = bl(2);
    lvars j, j0 = bl(3), j1 = bl(4);
    newarray([^j0 ^j1 ^i0 ^i1], 0) -> res;
    for i from i0 to i1 do
        for j from j0 to j1 do
            m(i, j) -> res(j, i);
        endfor;
    endfor;
enddefine;

PostScript

Library: initlib
/transpose {
    [ exch {
        { {empty? exch pop} map all?} {pop exit} ift
        [ exch {} {uncons {exch cons} dip exch} fold counttomark 1 roll] uncons
    } loop ] {reverse} map
}.

PowerBASIC

PowerBASIC has the MAT statement to simplify Matrix Algebra calculations; in conjunction with the TRN operation the actual transposition is just a one-liner.

#COMPILE EXE
#DIM ALL
#COMPILER PBCC 6
'----------------------------------------------------------------------
SUB TransposeMatrix(InitMatrix() AS DWORD, TransposedMatrix() AS DWORD)
LOCAL l1, l2, u1, u2 AS LONG
  l1 = LBOUND(InitMatrix, 1)
  l2 = LBOUND(InitMatrix, 2)
  u1 = UBOUND(InitMatrix, 1)
  u2 = UBOUND(InitMatrix, 2)
  REDIM TransposedMatrix(l2 TO u2, l1 TO u1)
  MAT TransposedMatrix() = TRN(InitMatrix())
END SUB
'----------------------------------------------------------------------
SUB PrintMatrix(a() AS DWORD)
LOCAL l1, l2, u1, u2, r, c AS LONG
LOCAL s AS STRING * 8
  l1 = LBOUND(a(), 1)
  l2 = LBOUND(a(), 2)
  u1 = UBOUND(a(), 1)
  u2 = UBOUND(a(), 2)
  FOR r = l1 TO u1
    FOR c = l2 TO u2
      RSET s = STR$(a(r, c))
      CON.PRINT s;
    NEXT c
  CON.PRINT
  NEXT r
END SUB
'----------------------------------------------------------------------
SUB TranspositionDemo(BYVAL DimSize1 AS DWORD, BYVAL DimSize2 AS DWORD)
LOCAL r, c, cc AS DWORD
LOCAL a() AS DWORD
LOCAL b() AS DWORD
  cc = DimSize2
  DECR DimSize1
  DECR DimSize2
  REDIM a(0 TO DimSize1, 0 TO DimSize2)
  FOR r = 0 TO DimSize1
    FOR c = 0 TO DimSize2
      a(r, c)= (cc * r) + c + 1
    NEXT c
  NEXT r
  CON.PRINT "initial matrix:"
  PrintMatrix a()
  TransposeMatrix a(), b()
  CON.PRINT "transposed matrix:"
  PrintMatrix b()
END SUB
'----------------------------------------------------------------------
FUNCTION PBMAIN () AS LONG
  TranspositionDemo 3, 3
  TranspositionDemo 3, 7
END FUNCTION
Output:
initial matrix:
       1       2       3
       4       5       6
       7       8       9
transposed matrix:
       1       4       7
       2       5       8
       3       6       9
initial matrix:
       1       2       3       4       5       6       7
       8       9      10      11      12      13      14
      15      16      17      18      19      20      21
transposed matrix:
       1       8      15
       2       9      16
       3      10      17
       4      11      18
       5      12      19
       6      13      20
       7      14      21

PowerShell

Any Matrix

function transpose($a) {
    $arr = @()
    if($a) { 
        $n = $a.count - 1 
        if(0 -lt $n) { 
            $m = ($a | foreach {$_.count} | measure-object -Minimum).Minimum - 1
            if( 0 -le $m) {
                if (0 -lt $m) {
                    $arr =@(0)*($m+1)
                    foreach($i in 0..$m) {
                        $arr[$i] = foreach($j in 0..$n) {@($a[$j][$i])}    
                    }
                } else {$arr = foreach($row in $a) {$row[0]}}
            }
        } else {$arr = $a}
    }
    $arr
} 
function show($a) {
    if($a) { 
        0..($a.Count - 1) | foreach{ if($a[$_]){"$($a[$_])"}else{""} }
    }
}
 
$a = @(@(2, 0, 7, 8),@(3, 5, 9, 1),@(4, 1, 6, 3))
"`$a ="
show $a
""
"transpose `$a ="
show (transpose $a)
""
$a = @(1)
"`$a ="
show $a
""
"transpose `$a ="
show (transpose $a)
""
"`$a ="
$a = @(1,2,3)
show $a
""
"transpose `$a ="
"$(transpose $a)"
""
"`$a ="
$a = @(@(4,7,8),@(1),@(2,3))
show $a
""
"transpose `$a ="
"$(transpose $a)"
""
"`$a ="
$a = @(@(4,7,8),@(1,5,9,0),@(2,3))
show $a
""
"transpose `$a ="
show (transpose $a)

Output:

$a =
2 0 7 8
3 5 9 1
4 1 6 3

transpose $a =
2 3 4
0 5 1
7 9 6
8 1 3

$a =
1

transpose $a =
1

$a =
1
2
3

transpose $a =
1 2 3

$a =
4 7 8
1
2 3

transpose $a =
4 1 2

$a =
4 7 8
1 5 9 0
2 3

transpose $a =
4 1 2
7 5 3

Square Matrix

function transpose($a) {
    if($a) { 
        $n = $a.Count - 1 
        foreach($i in 0..$n) { 
            $j = 0
            while($j -lt $i) {
                $a[$i][$j], $a[$j][$i] = $a[$j][$i], $a[$i][$j]
                $j++
            }    
        }
    }
    $a
}
function show($a) {
    if($a) { 
        0..($a.Count - 1) | foreach{ if($a[$_]){"$($a[$_])"}else{""} }
    }
}
$a = @(@(2, 4, 7),@(3, 5, 9),@(4, 1, 6))
show $a
""
show (transpose $a)

Output:

 
2 4 7
3 5 9
4 1 6

2 3 4
4 5 1
7 9 6

Prolog

Predicate transpose/2 exists in libray clpfd of SWI-Prolog.
In Prolog, a matrix is a list of lists. transpose/2 can be written like that.

Works with: SWI-Prolog
% transposition of a rectangular matrix
% e.g.   [[1,2,3,4], [5,6,7,8]]
% give [[1,5],[2,6],[3,7],[4,8]]

transpose(In, Out) :-
    In = [H | T],
    maplist(initdl, H, L),
    work(T, In, Out).

% we use the difference list to make "quick" appends (one inference)
initdl(V, [V | X] - X).

work(Lst, [H], Out) :-
	maplist(my_append_last, Lst, H, Out).

work(Lst, [H | T], Out) :-
    maplist(my_append, Lst, H, Lst1),
    work(Lst1, T, Out).

my_append(X-Y, C, X1-Y1) :-
    append_dl(X-Y, [C | U]- U, X1-Y1).

my_append_last(X-Y, C, X1) :-
	append_dl(X-Y, [C | U]- U, X1-[]).

% "quick" append
append_dl(X-Y, Y-Z, X-Z).

PureBasic

Matrices represented by integer arrays using rows as the first dimension and columns as the second dimension.

Procedure transposeMatrix(Array a(2), Array trans(2))
  Protected rows, cols
  
  Protected ar = ArraySize(a(), 1) ;rows in original matrix
  Protected ac = ArraySize(a(), 2) ;cols in original matrix
  
  ;size the matrix receiving the transposition
  Dim trans(ac, ar)
  
  ;copy the values
  For rows = 0 To ar
    For cols = 0 To ac
      trans(cols, rows) = a(rows, cols)
    Next
  Next  
EndProcedure

Procedure displayMatrix(Array a(2), text.s = "")
  Protected i, j 
  Protected cols = ArraySize(a(), 2), rows = ArraySize(a(), 1)
  
  PrintN(text + ": (" + Str(rows + 1) + ", " + Str(cols + 1) + ")")
  For i = 0 To rows
    For j = 0 To cols
      Print(LSet(Str(a(i, j)), 4, " "))
    Next
    PrintN("")
  Next
  PrintN("")
EndProcedure

;setup a matrix of arbitrary size
Dim m(random(5), random(5))

Define rows, cols
;fill matrix with 'random' data
For rows = 0 To ArraySize(m(),1)      ;ArraySize() can take a dimension as its second argument
  For cols = 0 To ArraySize(m(), 2)
    m(rows, cols) = random(10) - 10 
  Next
Next

Dim t(0,0) ;this will be resized during transposition
If OpenConsole()
  displayMatrix(m(), "matrix before transposition")
  transposeMatrix(m(), t())
  displayMatrix(t(), "matrix after transposition")
   
  Print(#CRLF$ + #CRLF$ + "Press ENTER to exit")
  Input()
  CloseConsole()
EndIf
Output:
matrix m, before: (3, 4)
-4  -9  -7  -9
-3  -6  -4  -6
-1  -2  0   -6

matrix m after transposition: (4, 3)
-4  -3  -1
-9  -6  -2
-7  -4  0
-9  -6  -6

Python

m=((1,  1,  1,   1),
   (2,  4,  8,  16),
   (3,  9, 27,  81),
   (4, 16, 64, 256),
   (5, 25,125, 625))
print(zip(*m))
# in Python 3.x, you would do:
# print(list(zip(*m)))
Output:
 [(1, 2, 3, 4, 5),
  (1, 4, 9, 16, 25),
  (1, 8, 27, 64, 125),
  (1, 16, 81, 256, 625)]

Note, however, that zip, while very useful, doesn't give us a simple type-safe transposition – it is actually a 'transpose + coerce' function rather than a pure transpose function; polymorphic in its inputs, but not in its outputs.

zip accepts matrices in any of the 4 permutations of (outer lists or tuples) * (inner lists or tuples), but it always and only returns a zip of tuples, losing any information about what the input type was.

For type-specific transpositions without coercion (and for a richer set of matrix types, and higher level of efficiency – transpositions are an inherently expensive operation) we can turn to numpy.

Meanwhile, for the four basic types of Python matrices (the cartesian product of (inner type, container type) * (tuple, list), the simplest (though not necessarily most efficient) approach (in the absence of numpy) may be to write a type-sensitive wrapper, which retains and restores the type information that zip discards.

Perhaps, for example, something like:

# transpose :: Matrix a -> Matrix a
def transpose(m):
    if m:
        inner = type(m[0])
        z = zip(*m)
        return (type(m))(
            map(inner, z) if tuple != inner else z
        )
    else:
        return m


if __name__ == '__main__':

    # TRANSPOSING FOUR BASIC TYPES OF PYTHON MATRIX
    # Cartesian product of (Outer, Inner) with (List, Tuple)

    # Matrix any = Tuple of Tuples of any type
    tts = ((1, 2, 3), (4, 5, 6), (7, 8, 9))

    # Matrix any = Tuple of Lists of any  type
    tls = ([1, 2, 3], [4, 5, 6], [7, 8, 9])

    emptyTuple = ()

    # Matrix any = List of Lists of any type
    lls = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]

    # Matrix any = List of Tuples of any type
    lts = [(1, 2, 3), (4, 5, 6), (7, 8, 9)]

    emptyList = []

    print('transpose function :: (Transposition without type change):\n')
    for m in [emptyTuple, tts, tls, emptyList, lls, lts]:
        tm = transpose(m)
        print (
            type(tm).__name__ + (
                (' of ' + type(tm[0]).__name__) if m else ''
            ) + ' :: ' + str(m) + ' -> ' + str(tm)
        )
Output:
transpose function :: (Transposition without type change):

tuple :: () -> ()
tuple of tuple :: ((1, 2, 3), (4, 5, 6), (7, 8, 9)) -> ((1, 4, 7), (2, 5, 8), (3, 6, 9))
tuple of list :: ([1, 2, 3], [4, 5, 6], [7, 8, 9]) -> ([1, 4, 7], [2, 5, 8], [3, 6, 9])
list :: [] -> []
list of list :: [[1, 2, 3], [4, 5, 6], [7, 8, 9]] -> [[1, 4, 7], [2, 5, 8], [3, 6, 9]]
list of tuple :: [(1, 2, 3), (4, 5, 6), (7, 8, 9)] -> [(1, 4, 7), (2, 5, 8), (3, 6, 9)]


Even with its type amnesia fixed, zip may still not be the instrument to reach for when it's possible that our matrices may contain gaps.

If any of the rows in a list of lists matrix are not wide enough for a full set of data for one or more of the columns, then zip(*xs) will drop all the data entirely, without warning or error message, returning no more than an empty list:

# Uneven list of lists
uls = [[10, 11], [20], [], [30, 31, 32]]

print (
    list(zip(*uls))
)

#  --> []

At this point, short of turning to numpy, we might need to write a custom function. An obvious approach is to return the full number of potential columns, each containing such data as the rows do have. For example:

Works with: Python version 3.7
'''Transposition of row sets with possible gaps'''

from collections import defaultdict


# listTranspose :: [[a]] -> [[a]]
def listTranspose(xss):
    '''Transposition of a matrix which may
       contain gaps.
    '''
    def go(xss):
        if xss:
            h, *t = xss
            return (
                [[h[0]] + [xs[0] for xs in t if xs]] + (
                    go([h[1:]] + [xs[1:] for xs in t])
                )
            ) if h and isinstance(h, list) else go(t)
        else:
            return []
    return go(xss)


# TEST ----------------------------------------------------
# main :: IO ()
def main():
    '''Tests with various lists of rows or non-row data.'''

    def labelledList(kxs):
        k, xs = kxs
        return k + ': ' + showList(xs)

    print(
        fTable(
            __doc__ + ':\n'
        )(labelledList)(fmapFn(showList)(snd))(
            fmapTuple(listTranspose)
        )([
            ('Square', [[1, 2, 3], [4, 5, 6], [7, 8, 9]]),
            ('Rectangle', [[1, 2, 3], [4, 5, 6], [7, 8, 9], [10, 11, 12]]),
            ('Rows with gaps', [[10, 11], [20], [], [31, 32, 33]]),
            ('Single row', [[1, 2, 3]]),
            ('Single row, one cell', [[1]]),
            ('Not rows', [1, 2, 3]),
            ('Nothing', [])
        ])
    )


# TEST RESULT FORMATTING ----------------------------------

# fTable :: String -> (a -> String) ->
#                     (b -> String) -> (a -> b) -> [a] -> String
def fTable(s):
    '''Heading -> x display function -> fx display function ->
                     f -> xs -> tabular string.
    '''
    def go(xShow, fxShow, f, xs):
        ys = [xShow(x) for x in xs]
        w = max(map(len, ys))
        return s + '\n' + '\n'.join(map(
            lambda x, y: y.rjust(w, ' ') + ' -> ' + fxShow(f(x)),
            xs, ys
        ))
    return lambda xShow: lambda fxShow: lambda f: lambda xs: go(
        xShow, fxShow, f, xs
    )


# fmapFn :: (a -> b) -> (r -> a) -> r -> b
def fmapFn(f):
    '''The application of f to the result of g.
       fmap over a function is composition.
    '''
    return lambda g: lambda x: f(g(x))


# fmapTuple :: (a -> b) -> (c, a) -> (c, b)
def fmapTuple(f):
    '''A pair in which f has been
       applied to the second item.
    '''
    return lambda ab: (ab[0], f(ab[1])) if (
        2 == len(ab)
    ) else None


# show :: a -> String
def show(x):
    '''Stringification of a value.'''
    def go(v):
        return defaultdict(lambda: repr, [
            ('list', showList)
            # ('Either', showLR),
            # ('Maybe', showMaybe),
            # ('Tree', drawTree)
        ])[
            typeName(v)
        ](v)
    return go(x)


# showList :: [a] -> String
def showList(xs):
    '''Stringification of a list.'''
    return '[' + ','.join(show(x) for x in xs) + ']'


# snd :: (a, b) -> b
def snd(tpl):
    '''Second member of a pair.'''
    return tpl[1]


# typeName :: a -> String
def typeName(x):
    '''Name string for a built-in or user-defined type.
       Selector for type-specific instances
       of polymorphic functions.
    '''
    if isinstance(x, dict):
        return x.get('type') if 'type' in x else 'dict'
    else:
        return 'iter' if hasattr(x, '__next__') else (
            type(x).__name__
        )

# MAIN ---
if __name__ == '__main__':
    main()
Output:
Transposition of row sets with possible gaps:

              Square: [[1,2,3],[4,5,6],[7,8,9]] -> [[1,4,7],[2,5,8],[3,6,9]]
Rectangle: [[1,2,3],[4,5,6],[7,8,9],[10,11,12]] -> [[1,4,7,10],[2,5,8,11],[3,6,9,12]]
   Rows with gaps: [[10,11],[20],[],[31,32,33]] -> [[10,20,31],[11,32],[33]]
                          Single row: [[1,2,3]] -> [[1],[2],[3]]
                    Single row, one cell: [[1]] -> [[1]]
                              Not rows: [1,2,3] -> []
                                    Nothing: [] -> []

Quackery

  [ ' [ [ ] ] 
    over 0 peek size of 
    [] rot
    witheach join
    witheach
      [ dip behead 
        nested join
        nested join ] ] is transpose ( [ --> [ )

  ' [ [ 1 2 ] [ 3 4 ] [ 5 6 ] ] 
  dup echo cr cr
  transpose dup echo cr cr
  transpose echo cr
Output:
[ [ 1 2 ] [ 3 4 ] [ 5 6 ] ]

[ [ 1 3 5 ] [ 2 4 6 ] ]

[ [ 1 2 ] [ 3 4 ] [ 5 6 ] ]

R

b <- 1:5
m <- matrix(c(b, b^2, b^3, b^4), 5, 4)
print(m)
tm <- t(m)
print(tm)

Racket

#lang racket
(require math)
(matrix-transpose (matrix [[1 2] [3 4]]))
Output:
(array #[#[1 3] #[2 4]])

(Another method, without math, and using lists is demonstrated in the Scheme solution.)

Raku

(formerly Perl 6)

Works with: rakudo version 2018.03
# Transposition can be done with the reduced zip meta-operator
# on list-of-lists data structures

say [Z] (<A B C D>, <E F G H>, <I J K L>);

# For native shaped arrays, a more traditional procedure of copying item-by-item
# Here the resulting matrix is also a native shaped array

my @a[3;4] =
  [
    [<A B C D>],
    [<E F G H>],
    [<I J K L>],
  ];

(my $n, my $m) = @a.shape;
my @b[$m;$n];
for ^$m X ^$n -> (\i, \j) {
   @b[i;j] = @a[j;i];
}

say @b;
Output:
((A E I) (B F J) (C G K) (D H L))
[[A E I] [B F J] [C G K] [D H L]]

Rascal

public rel[real, real, real] matrixTranspose(rel[real x, real y, real v] matrix){
    return {<y, x, v> | <x, y, v> <- matrix};
}

//a matrix
public rel[real x, real y, real v] matrixA = {
<0.0,0.0,12.0>, <0.0,1.0, 6.0>, <0.0,2.0,-4.0>, 
<1.0,0.0,-51.0>, <1.0,1.0,167.0>, <1.0,2.0,24.0>, 
<2.0,0.0,4.0>, <2.0,1.0,-68.0>, <2.0,2.0,-41.0>
};

REXX

/*REXX program transposes any sized rectangular matrix, displays before & after matrices*/
@.=;     @.1 =   1.02     2.03      3.04       4.05        5.06         6.07          7.08
         @.2 = 111     2222     33333     444444     5555555     66666666     777777777
w=0
                             do    row=1  while @.row\==''
                                do col=1  until @.row==''; parse var @.row A.row.col @.row
                                w=max(w, length(A.row.col) )    /*max width for elements*/
                                end   /*col*/                   /*(used to align ouput).*/
                             end      /*row*/    /* [↑]  build matrix A from the @ lists*/
row= row-1                                       /*adjust for  DO  loop index increment.*/
                             do    j=1  for row  /*process each    row    of the matrix.*/
                                do k=1  for col  /*   "      "    column   "  "     "   */
                                B.k.j= A.j.k     /*transpose the  A  matrix  (into  B). */
                                end   /*k*/
                             end      /*j*/
call showMat  'A', row, col                      /*display the   A   matrix to terminal.*/
call showMat  'B', col, row                      /*   "     "    B      "    "     "    */
exit                                             /*stick a fork in it,  we're all done. */
/*──────────────────────────────────────────────────────────────────────────────────────*/
showMat: arg mat,rows,cols;     say;       say center( mat  'matrix',  (w+1)*cols +4, "─")
                 do      r=1  for rows;    _=                                  /*newLine*/
                      do c=1  for cols;    _=_ right( value( mat'.'r"."c), w)  /*append.*/
                      end   /*c*/
                 say _                                                         /*1 line.*/
                 end        /*r*/;         return
output   when using the default input:
─────────────────────────────────A matrix─────────────────────────────────
      1.02      2.03      3.04      4.05      5.06      6.07      7.08
       111      2222     33333    444444   5555555  66666666 777777777

────────B matrix────────
      1.02       111
      2.03      2222
      3.04     33333
      4.05    444444
      5.06   5555555
      6.07  66666666
      7.08 777777777

Ring

load "stdlib.ring"
transpose = newlist(5,4)
matrix = [[78,19,30,12,36], [49,10,65,42,50], [30,93,24,78,10], [39,68,27,64,29]]
for i = 1 to 5
    for j = 1 to 4
        transpose[i][j] = matrix[j][i]
        see "" + transpose[i][j] + " "
    next
    see nl
next

Output:

78 49 30 39
19 10 93 68
30 65 24 27
12 42 78 64
36 50 10 29

RLaB

 >> m = rand(3,5)
  0.41844289   0.476591435    0.75054022   0.226388925   0.963880314
  0.91267171   0.941762397   0.464227895   0.693482786   0.203839405
 0.261512966   0.157981873    0.26582235    0.11557427  0.0442493069
>> m'
  0.41844289    0.91267171   0.261512966
 0.476591435   0.941762397   0.157981873
  0.75054022   0.464227895    0.26582235
 0.226388925   0.693482786    0.11557427
 0.963880314   0.203839405  0.0442493069

RPL

[[1 2 3 4][5 6 7 8][9 10 11 12]] TRN
Output:
[[1 5 9] [2 6 10] [3 7 11] [4 8 12]]

Ruby

m=[[1,  1,  1,   1],
   [2,  4,  8,  16],
   [3,  9, 27,  81],
   [4, 16, 64, 256],
   [5, 25,125, 625]]
puts m.transpose
Output:
 [[1, 2, 3, 4, 5], [1, 4, 9, 16, 25], [1, 8, 27, 64, 125], [1, 16, 81, 256, 625]]

or using 'matrix' from the standard library

require 'matrix'

m=Matrix[[1,  1,  1,   1],
         [2,  4,  8,  16],
         [3,  9, 27,  81],
         [4, 16, 64, 256],
         [5, 25,125, 625]]
puts m.transpose
Output:
 Matrix[[1, 2, 3, 4, 5], [1, 4, 9, 16, 25], [1, 8, 27, 64, 125], [1, 16, 81, 256, 625]]

or using zip:

def transpose(m)
  m[0].zip(*m[1..-1])
end
p transpose([[1,2,3],[4,5,6]])
Output:
  [[1, 4], [2, 5], [3, 6]]

Run BASIC

mtrx$ ="4, 3,   0, 0.10, 0.20, 0.30,   0.40, 0.50, 0.60, 0.70,  0.80, 0.90, 1.00, 1.10"
 
print "Transpose of matrix"
call DisplayMatrix mtrx$
print "         ="
MatrixT$ =MatrixTranspose$(mtrx$)
call DisplayMatrix MatrixT$

end

function MatrixTranspose$(in$)
  w	= val(word$(in$, 1, ","))    '   swap w and h parameters
  h	= val(word$(in$, 2, ","))
  t$	= str$(h); ","; str$(w); ","
  for i =1 to w
    for j =1 to h
      t$ = t$ +word$(in$, 2 +i +(j -1) *w, ",") +","
    next j
  next i
MatrixTranspose$ =left$(t$, len(t$) -1)
end function
    
sub DisplayMatrix in$   '   Display looking like a matrix!
html "<table border=2>"
  w	= val(word$(in$, 1, ","))
  h	= val(word$(in$, 2, ","))
  for i =0 to h -1
   html "<tr align=right>"
   for j =1 to w
      term$	= word$(in$, j +2 +i *w, ",")
      html "<td>";val(term$);"</td>"
    next j
html "</tr>"
next i
html "</table>"
end sub
Output:

Transpose of matrix

00.10.20.3
0.40.50.60.7
0.80.91.01.1

=

00.40.8
0.10.50.9
0.20.61.0
0.30.71.1

Rust

version 1

struct Matrix {
    dat: [[i32; 3]; 3]
}
 

 
impl Matrix {
    pub fn transpose_m(a: Matrix) -> Matrix
    {
        let mut out = Matrix {
            dat: [[0, 0, 0],
                  [0, 0, 0],
                  [0, 0, 0]
                  ]
        };
        
        for i in 0..3{
            for j in 0..3{
                
                    out.dat[i][j] = a.dat[j][i];
            }
        }
 
        out
    }
 
    pub fn print(self)
    {
        for i in 0..3 {
            for j in 0..3 {
                print!("{} ", self.dat[i][j]);
            }
            print!("\n");
        }
    }
}
 
fn main()
{
    let  a = Matrix {
        dat: [[1, 2, 3],
              [4, 5, 6],
              [7, 8, 9] ]
    };

let c = Matrix::transpose_m(a);
    c.print();
}

version 2

fn main() {
    let m = vec![vec![1, 2, 3], vec![4, 5, 6]];
    println!("Matrix:\n{}", matrix_to_string(&m));
    let t = matrix_transpose(m);
    println!("Transpose:\n{}", matrix_to_string(&t));
}

fn matrix_to_string(m: &Vec<Vec<i32>>) -> String {
    m.iter().fold("".to_string(), |a, r| {
        a + &r
            .iter()
            .fold("".to_string(), |b, e| b + "\t" + &e.to_string())
            + "\n"
    })
}

fn matrix_transpose(m: Vec<Vec<i32>>) -> Vec<Vec<i32>> {
    let mut t = vec![Vec::with_capacity(m.len()); m[0].len()];
    for r in m {
        for i in 0..r.len() {
            t[i].push(r[i]);
        }
    }
    t
}

Output:

Matrix:
	1	2	3
	4	5	6

Transpose:
	1	4
	2	5
	3	6

Scala

scala> Array.tabulate(4)(i => Array.tabulate(4)(j => i*4 + j))
res12: Array[Array[Int]] = Array(Array(0, 1, 2, 3), Array(4, 5, 6, 7), Array(8, 9, 10, 11), Array(12, 13, 14, 15))

scala> res12.transpose
res13: Array[Array[Int]] = Array(Array(0, 4, 8, 12), Array(1, 5, 9, 13), Array(2, 6, 10, 14), Array(3, 7, 11, 15))

scala> res12 map (_ map ("%2d" format _) mkString " ") mkString "\n"
res16: String =
 0  1  2  3
 4  5  6  7
 8  9 10 11
12 13 14 15

scala> res13 map (_ map ("%2d" format _) mkString " ") mkString "\n"
res17: String =
 0  4  8 12
 1  5  9 13
 2  6 10 14
 3  7 11 15

Scheme

(define (transpose m)
  (apply map list m))

Seed7

$ include "seed7_05.s7i";
  include "float.s7i";

const type: matrix is array array float;

const func matrix: transpose (in matrix: aMatrix) is func
  result
    var matrix: transposedMatrix is matrix.value;
  local
    var integer: i is 0;
    var integer: j is 0;
  begin
    transposedMatrix := length(aMatrix[1]) times length(aMatrix) times 0.0;
    for i range 1 to length(aMatrix) do
      for j range 1 to length(aMatrix[1]) do
        transposedMatrix[j][i] := aMatrix[i][j];
      end for;
    end for;
  end func;

const proc: write (in matrix: aMatrix) is func
  local
    var integer: line is 0;
    var integer: column is 0;
  begin
    for line range 1 to length(aMatrix) do
      for column range 1 to length(aMatrix[line]) do
        write(" " <& aMatrix[line][column] digits 2);
      end for;
      writeln;
    end for;
  end func;

const matrix: testMatrix is [] (
    [] (0.0, 0.1, 0.2, 0.3),
    [] (0.4, 0.5, 0.6, 0.7),
    [] (0.8, 0.9, 1.0, 1.1));

const proc: main is func
  begin
    writeln("Before Transposition:");
    write(testMatrix);
    writeln;
    writeln("After Transposition:");
    write(transpose(testMatrix));
  end func;
Output:
Before Transposition:
 0.00 0.10 0.20 0.30
 0.40 0.50 0.60 0.70
 0.80 0.90 1.00 1.10

After Transposition:
 0.00 0.40 0.80
 0.10 0.50 0.90
 0.20 0.60 1.00
 0.30 0.70 1.10

SETL

program matrix_transposition;
    mat := [[1,2,3,4], [5,6,7,8], [9,10,11,12]];
    print(mat);
    print(' -> ');
    print(transpose(mat));

    proc transpose(m);
        return [[m(y)(x) : y in [1..#m]] : x in [1..#m(1)]];
    end proc;
end program;
Output:
[[1 2 3 4] [5 6 7 8] [9 10 11 12]]
 ->
[[1 5 9] [2 6 10] [3 7 11] [4 8 12]]

Sidef

func transpose(matrix) {
    matrix[0].range.map{|i| matrix.map{_[i]}};
};

var m = [
  [1,  1,   1,   1],
  [2,  4,   8,  16],
  [3,  9,  27,  81],
  [4, 16,  64, 256],
  [5, 25, 125, 625],
];

transpose(m).each { |row|
    "%5d" * row.len -> printlnf(row...);
}
Output:
    1    2    3    4    5
    1    4    9   16   25
    1    8   27   64  125
    1   16   81  256  625

SPAD

Works with: FriCAS
Works with: OpenAxiom
Works with: Axiom
(1) -> originalMatrix := matrix [[1, 1, 1, 1],[2, 4, 8, 16], _
                                 [3, 9, 27, 81],[4, 16, 64, 256], _
                                 [5, 25, 125, 625]]

        +1  1    1    1 +
        |               |
        |2  4    8   16 |
        |               |
   (1)  |3  9   27   81 |
        |               |
        |4  16  64   256|
        |               |
        +5  25  125  625+
                                                        Type: Matrix(Integer)
(2) -> transposedMatrix := transpose(originalMatrix)

        +1  2   3    4    5 +
        |                   |
        |1  4   9   16   25 |
   (2)  |                   |
        |1  8   27  64   125|
        |                   |
        +1  16  81  256  625+
                                                        Type: Matrix(Integer)

Domain:Matrix(R)

Sparkling

function transpose(A) {
    return map(range(sizeof A), function(k, idx) {
        return map(A, function(k, row) {
            return row[idx];
        });
    });
}

Stata

Stata matrices are always real, so there is no ambiguity about the transpose operator. Mata matrices, however, may be real or complex. The transpose operator is actually a conjugate transpose, but there is also a transposeonly() function.

Stata matrices

. mat a=1,2,3\4,5,6
. mat b=a'
. mat list a

a[2,3]
    c1  c2  c3
r1   1   2   3
r2   4   5   6

. mat list b

b[3,2]
    r1  r2
c1   1   4
c2   2   5
c3   3   6

Mata

: a=1,1i

: a
        1    2
    +-----------+
  1 |   1   1i  |
    +-----------+

: a'
         1
    +-------+
  1 |    1  |
  2 |  -1i  |
    +-------+

: transposeonly(a)
        1
    +------+
  1 |   1  |
  2 |  1i  |
    +------+

Swift

@inlinable
public func matrixTranspose<T>(_ matrix: [[T]]) -> [[T]] {
  guard !matrix.isEmpty else {
    return []
  }

  var ret = Array(repeating: [T](), count: matrix[0].count)

  for row in matrix {
    for j in 0..<row.count {
      ret[j].append(row[j])
    }
  }

  return ret
}

@inlinable
public func printMatrix<T>(_ matrix: [[T]]) {
  guard !matrix.isEmpty else {
    print()

    return
  }

  let rows = matrix.count
  let cols = matrix[0].count

  for i in 0..<rows {
    for j in 0..<cols {
      print(matrix[i][j], terminator: " ")
    }

    print()
  }
}

let m1 = [
  [1, 2, 3],
  [4, 5, 6]
]

print("Input:")
printMatrix(m1)


let m2 = matrixTranspose(m1)

print("Output:")
printMatrix(m2)
Output:
Input:
1 2 3 
4 5 6 
Output:
1 4 
2 5 
3 6

Tailspin

templates transpose
  def a: $;
  [1..$a(1)::length -> $a(1..last;$)] !
end transpose
 
templates printMatrix&{w:}
  templates formatN
    @: [];
    $ -> #
    '$@ -> $::length~..$w -> ' ';$@(last..1:-1)...;' !
    when <1..> do ..|@: $ mod 10; $ ~/ 10 -> #
  end formatN
  $... -> '|$(1) -> formatN;$(2..last)... -> ', $ -> formatN;';|
' !
end printMatrix
 
def m: [[1, 2, 3, 4], [5, 6, 7, 8], [9, 10, 11, 12]];
'before:
' -> !OUT::write
$m -> printMatrix&{w:2} -> !OUT::write
 
def mT: $m -> transpose;
'
transposed:
' -> !OUT::write
$mT -> printMatrix&{w:2} -> !OUT::write

v0.5

transpose templates
  a is $;
  $a(1; .. as j; -> $a(..; $j)) !
end transpose

printMatrix templates
  formatN templates
    @ set [];
    $ -> !#
    '$@ -> $::length~..2 -> ' ';$@(..:-1)...;' !
    when <|1..> do ..|@ set $ mod 10; $ ~/ 10 -> !#
  end formatN
  $... -> '|$($::first) -> formatN;$(~..)... -> ', $ -> formatN;';|
' !
end printMatrix

m is [[1, 2, 3, 4], [5, 6, 7, 8], [9, 10, 11, 12]];
'before:
' !
$m -> printMatrix !
 
mT is $m -> transpose;
'
transposed:
' !
$mT -> printMatrix !
Output:
before:
| 1,  2,  3,  4|
| 5,  6,  7,  8|
| 9, 10, 11, 12|

transposed:
| 1,  5,  9|
| 2,  6, 10|
| 3,  7, 11|
| 4,  8, 12|

Tcl

With core Tcl, representing a matrix as a list of lists:

package require Tcl 8.5
namespace path ::tcl::mathfunc

proc size {m} {
    set rows [llength $m]
    set cols [llength [lindex $m 0]]
    return [list $rows $cols]
}
proc transpose {m} {
    lassign [size $m] rows cols 
    set new [lrepeat $cols [lrepeat $rows ""]]
    for {set i 0} {$i < $rows} {incr i} {
        for {set j 0} {$j < $cols} {incr j} {
            lset new $j $i [lindex $m $i $j]
        }
    }
    return $new
}
proc print_matrix {m {fmt "%.17g"}} {
    set max [widest $m $fmt]
    lassign [size $m] rows cols 
    for {set i 0} {$i < $rows} {incr i} {
        for {set j 0} {$j < $cols} {incr j} {
	    set s [format $fmt [lindex $m $i $j]]
            puts -nonewline [format "%*s " [lindex $max $j] $s]
        }
        puts ""
    }
}
proc widest {m {fmt "%.17g"}} {
    lassign [size $m] rows cols 
    set max [lrepeat $cols 0]
    for {set i 0} {$i < $rows} {incr i} {
        for {set j 0} {$j < $cols} {incr j} {
	    set s [format $fmt [lindex $m $i $j]]
            lset max $j [max [lindex $max $j] [string length $s]]
        }
    }
    return $max
}

set m {{1 1 1 1} {2 4 8 16} {3 9 27 81} {4 16 64 256} {5 25 125 625}}
print_matrix $m "%d"
print_matrix [transpose $m] "%d"
Output:
1  1   1   1 
2  4   8  16 
3  9  27  81 
4 16  64 256 
5 25 125 625 
1  2  3   4   5 
1  4  9  16  25 
1  8 27  64 125 
1 16 81 256 625
Library: Tcllib (Package: struct::matrix)
package require struct::matrix
struct::matrix M
M deserialize {5 4 {{1 1 1 1} {2 4 8 16} {3 9 27 81} {4 16 64 256} {5 25 125 625}}}
M format 2string
M transpose
M format 2string
Output:
1 1  1   1  
2 4  8   16 
3 9  27  81 
4 16 64  256
5 25 125 625
1 2 3 4 5
1 4 9 16 25
         
1 8 27 64 125
         
         
1 16 81 256 625
         
         

TI-83 BASIC , TI-89 BASIC

TI-83: Assuming the original matrix is in [A], place its transpose in [B]:

[A]T->[B]

The T operator can be found in the matrix math menu.

TI-89: The same except that matrix variables do not have special names:

AT → B


True BASIC

OPTION BASE 0
DIM matriz(3, 4)
DATA 78, 19, 30, 12, 36
DATA 49, 10, 65, 42, 50
DATA 30, 93, 24, 78, 10
DATA 39, 68, 27, 64, 29

FOR f = 0 TO 3
    FOR c = 0 TO 4
        READ matriz(f, c)
    NEXT c
NEXT f

DIM mtranspuesta(0 TO 4, 0 TO 3)

FOR fila = LBOUND(matriz,1) TO UBOUND(matriz,1)
    FOR columna = LBOUND(matriz,2) TO UBOUND(matriz,2)
        LET mtranspuesta(columna, fila) = matriz(fila, columna)
        PRINT matriz(fila, columna);
    NEXT columna
    PRINT
NEXT fila
PRINT

FOR fila = LBOUND(mtranspuesta,1) TO UBOUND(mtranspuesta,1)
    FOR columna = LBOUND(mtranspuesta,2) TO UBOUND(mtranspuesta,2)
        PRINT mtranspuesta(fila, columna);
    NEXT columna
    PRINT
NEXT fila
END


Ursala

Matrices are stored as lists of lists, and transposing them is a built in operation.

#cast %eLL

example = 

~&K7 <
   <1.,2.,3.,4.>,
   <5.,6.,7.,8.>,
   <9.,10.,11.,12.>>

For a more verbose version, replace the ~&K7 operator with the standard library function named transpose.

Output:
<
   <1.000000e+00,5.000000e+00,9.000000e+00>,
   <2.000000e+00,6.000000e+00,1.000000e+01>,
   <3.000000e+00,7.000000e+00,1.100000e+01>,
   <4.000000e+00,8.000000e+00,1.200000e+01>>

VBA

Function transpose(m As Variant) As Variant
    transpose = WorksheetFunction.transpose(m)
End Function

VBScript

'create and display the initial matrix
WScript.StdOut.WriteLine "Initial Matrix:"
x = 4 : y = 6 : n = 1
Dim matrix()
ReDim matrix(x,y)
For i = 0 To y
	For j = 0 To x
		matrix(j,i) = n
		If j < x Then
			WScript.StdOut.Write n & vbTab
		Else
			WScript.StdOut.Write n
		End If
		n = n + 1
	Next
	WScript.StdOut.WriteLine
Next

'display the trasposed matrix
WScript.StdOut.WriteBlankLines(1)
WScript.StdOut.WriteLine "Transposed Matrix:"
For i = 0 To x
	For j = 0 To y
		If j < y Then
			WScript.StdOut.Write matrix(i,j) & vbTab
		Else
			WScript.StdOut.Write matrix(i,j)
		End If
	Next
	WScript.StdOut.WriteLine
Next
Output:
Initial Matrix:
1	2	3	4	5
6	7	8	9	10
11	12	13	14	15
16	17	18	19	20
21	22	23	24	25
26	27	28	29	30
31	32	33	34	35

Transposed Matrix:
1	6	11	16	21	26	31
2	7	12	17	22	27	32
3	8	13	18	23	28	33
4	9	14	19	24	29	34
5	10	15	20	25	30	35

Visual Basic

Translation of: PowerBASIC
Works with: Visual Basic version 5
Works with: Visual Basic version 6
Option Explicit
'----------------------------------------------------------------------
Function TransposeMatrix(InitMatrix() As Long, TransposedMatrix() As Long)
Dim l1 As Long, l2 As Long, u1 As Long, u2 As Long, r As Long, c As Long
  l1 = LBound(InitMatrix, 1)
  l2 = LBound(InitMatrix, 2)
  u1 = UBound(InitMatrix, 1)
  u2 = UBound(InitMatrix, 2)
  ReDim TransposedMatrix(l2 To u2, l1 To u1)
  For r = l1 To u1
    For c = l2 To u2
      TransposedMatrix(c, r) = InitMatrix(r, c)
    Next c
  Next r
End Function
'----------------------------------------------------------------------
Sub PrintMatrix(a() As Long)
Dim l1 As Long, l2 As Long, u1 As Long, u2 As Long, r As Long, c As Long
Dim s As String * 8
  l1 = LBound(a(), 1)
  l2 = LBound(a(), 2)
  u1 = UBound(a(), 1)
  u2 = UBound(a(), 2)
  For r = l1 To u1
    For c = l2 To u2
      RSet s = Str$(a(r, c))
      Debug.Print s;
    Next c
  Debug.Print
  Next r
End Sub
'----------------------------------------------------------------------
Sub TranspositionDemo(ByVal DimSize1 As Long, ByVal DimSize2 As Long)
Dim r, c, cc As Long
Dim a() As Long
Dim b() As Long
  cc = DimSize2
  DimSize1 = DimSize1 - 1
  DimSize2 = DimSize2 - 1
  ReDim a(0 To DimSize1, 0 To DimSize2)
  For r = 0 To DimSize1
    For c = 0 To DimSize2
      a(r, c) = (cc * r) + c + 1
    Next c
  Next r
  Debug.Print "initial matrix:"
  PrintMatrix a()
  TransposeMatrix a(), b()
  Debug.Print "transposed matrix:"
  PrintMatrix b()
End Sub
'----------------------------------------------------------------------
Sub Main()
  TranspositionDemo 3, 3
  TranspositionDemo 3, 7
End Sub
Output:
initial matrix:
       1       2       3
       4       5       6
       7       8       9
transposed matrix:
       1       4       7
       2       5       8
       3       6       9
initial matrix:
       1       2       3       4       5       6       7
       8       9      10      11      12      13      14
      15      16      17      18      19      20      21
transposed matrix:
       1       8      15
       2       9      16
       3      10      17
       4      11      18
       5      12      19
       6      13      20
       7      14      21

Wortel

The @zipm operator zips together an array of arrays, this is the same as transposition if the matrix is represented as an array of arrays.

@zipm [[1 2 3] [4 5 6] [7 8 9]]

Returns:

[[1 4 7] [2 5 8] [3 6 9]]

Wren

Library: Wren-matrix
Library: Wren-fmt
import "./matrix" for Matrix
import "./fmt" for Fmt

var m = Matrix.new([
    [ 1,  2,  3],
    [ 4,  5,  6],
    [ 7,  8,  9],
    [10, 11, 12]
])

System.print("Original:\n")
Fmt.mprint(m, 2, 0)
System.print("\nTransposed:\n")
Fmt.mprint(m.transpose, 2, 0)
Output:
Original:

| 1  2  3|
| 4  5  6|
| 7  8  9|
|10 11 12|

Transposed:

| 1  4  7 10|
| 2  5  8 11|
| 3  6  9 12|

XPL0

Separate memory for the transposed matrix must be used because of XPL0's unusual array configuration. It can't simply reorder the elements stored in the original array's memory.

proc Transpose(M, R, C, N);     \Transpose matrix M to N
int  M, R, C, N;                \rows and columns
int  I, J;
[for I:= 0 to R-1 do
    for J:= 0 to C-1 do
        N(J,I):= M(I,J);
];

proc ShowMat(M, R, C);          \Display matrix M
int  M, R, C;                   \rows and columns
int  I, J;
[for I:= 0 to R-1 do
    [for J:= 0 to C-1 do
        RlOut(0, float(M(I,J)));
    CrLf(0);
    ];
];

int M, N(4,3);
[M:= [[1, 2, 3, 4],             \3 rows by 4 columns
      [5, 6, 7, 8],
      [9,10,11,12]];
Format(4, 0);
ShowMat(M, 3, 4);
CrLf(0);
Transpose(M, 3, 4, N);
ShowMat(N, 4, 3);
]
Output:
   1   2   3   4
   5   6   7   8
   9  10  11  12

   1   5   9
   2   6  10
   3   7  11
   4   8  12

Yabasic

Translation of: FreeBASIC
dim matriz(4,5)
dim mtranspuesta(5,4)

for fila = 1 to arraysize(matriz(), 1)
    for columna = 1 to arraysize(matriz(), 2)
	    read matriz(fila, columna)
		print matriz(fila, columna);
		mtranspuesta(columna, fila) = matriz(fila, columna)
	next columna
	print
next fila
print

for fila = 1 to arraysize(mtranspuesta(), 1)
    for columna = 1 to arraysize(mtranspuesta(), 2)
		print mtranspuesta(fila, columna);
    next columna
	print
next fila
end

data 78,19,30,12,36
data 49,10,65,42,50
data 30,93,24,78,10
data 39,68,27,64,29


zkl

Using the GNU Scientific Library:

var [const] GSL=Import("zklGSL");	// libGSL (GNU Scientific Library)
GSL.Matrix(2,3).set(1,2,3, 4,5,6).transpose().format(5).println();  // in place
println("---");
GSL.Matrix(2,2).set(1,2, 3,4).transpose().format(5).println();  // in place
println("---");
GSL.Matrix(3,1).set(1,2,3).transpose().format(5).println();  // in place
Output:
 1.00, 4.00
 2.00, 5.00
 3.00, 6.00
---
 1.00, 3.00
 2.00, 4.00
---
 1.00, 2.00, 3.00

Or, using lists:

Translation of: Wortel
fcn transpose(M){
   if(M.len()==1) M[0].pump(List,List.create); // 1 row --> n columns
   else M[0].zip(M.xplode(1));
}

The list xplode method pushes list contents on to the call stack.

m:=T(T(1,2,3),T(4,5,6));          transpose(m).println();
m:=L(L(1,"a"),L(2,"b"),L(3,"c")); transpose(m).println();
transpose(L(L(1,2,3))).println();
transpose(L(L(1),L(2),L(3))).println();
transpose(L(L(1))).println();
Output:
L(L(1,4),L(2,5),L(3,6))
L(L(1,2,3),L("a","b","c"))
L(L(1),L(2),L(3))
(L(1,2,3))
L(L(1))

zonnon

module MatrixOps;
type
	Matrix = array {math} *,* of integer;


	procedure WriteMatrix(x: array {math} *,* of integer);
	var
		i,j: integer;
	begin
		for i := 0 to len(x,0) - 1 do
			for j := 0 to len(x,1) - 1 do
				write(x[i,j]);
			end;
			writeln;
		end	
	end WriteMatrix;

	procedure Transposition;
	var
		m,x: Matrix;
	begin
		m := [[1,2,3],[3,4,5]]; (* matrix initialization *)
		x := !m; (* matrix trasposition *)
		WriteMatrix(x);
	end Transposition;

begin
	Transposition;
end MatrixOps.