Arrays: Difference between revisions

This task is about arrays.

{{trans|Python}}

 

array.append(1)

array.append(3)

 

=={{header|360 Assembly}}==

ARRAYS PROLOG

* we use TA array with 1 as origin. So TA(1) to TA(20)

An array is little more than just a contiguous section of memory. Whether or not an array is mutable depends solely on whether it is defined in ROM or RAM. The syntax will be discussed in further detail in the Two-Dimensional Arrays section.

 

db 5,10,15,20,25,30,35,40,45,50</syntaxhighlight>

 

Looking up a value in an array is fairly straightforward. The best addressing modes for doing so are <code>LDA $????,x</code>,<code>LDA $????,y</code>, and <code>LDA ($??),y</code>. In this case, x or y represents the index into the array. To put it in terms of C:

 

{

char array[5] = {3,6,9,12,15};

 

would (theoretically) compile to the following in 6502 Assembly:

foo:

LDX #2 ;load the desired index

One important thing to note is a hardware bug involving <code>LDA $??,x</code>. If the sum of $?? and x would exceed 255, instead of continuing past $100, the CPU will actually wrap around back to $00. This does not happen with absolute addressing modes or indexed indirect with Y. Here's an example:

 

LDA $80,x ;evaluates to LDA $00

LDA $0480,x ;evaluates to LDA $0500</syntaxhighlight>

===Arrays of 16-Bit Data===

You can have arrays of 16-bit data as well as 8-bit ones. There are a few ways to do this, and we'll go over the "naive" way first:

dw $ABCD,$BEEF,$CAFE,$DADA</syntaxhighlight>

 

The 6502 is little-endian, so the above would be exactly the same as the following:

db $CD,$AB,$EF,$BE,$FE,$CA,$DA,$DA</syntaxhighlight>

 

To properly index a 16-bit array that's formatted as in the above example, you'll need to double your index. In this example, we'll be loading the offset of <code>$BEEF</code>:

LDA wordArray,X ;evaluates to LDA #$EF

STA $00 ;store in a zero page temporary variable

 

However, if you split the word table into two byte tables, you can actually get more bang for your buck, and it takes the same amount of memory no matter which way you store the data.

db $CD,$EF,$FE,$DA

 

If both wordArray_Lo and wordArray_Hi were 256 bytes each, you'd be able to index both of them no problem, where you wouldn't be able to do that if it were one array. Let's try loading <code>$BEEF</code> again:

 

LDA wordArray_Lo,x ;evaluates to LDA #$EF

STA $00

I'll let you in on a little secret: two-dimensional arrays don't exist. This is just as true for modern computers as it is the 6502.

In the first section I had this example of an array:

db 5,10,15,20,25,30,35,40,45,50</syntaxhighlight>

 

In the eyes of the CPU, this is the same as ANY of the following:

db 5

db 10

db 50</syntaxhighlight>

 

db 5,10

db 15,20

or any other way to write it you can imagine. All that matters is the order of the bytes in the array - as long as that is the same you can write it however you want. It's best to write it in the way it's meant to be interpreted, however. But in order to explain that to the computer you'll need a little bit of finesse. Let's pretend that the "correct" interpretation is this 5 by 2 array:

 

db 5,10

db 15,20

 

For this example, we want row 3 and column 1 (zero-indexed for both) which means we want to load 40.

LDA #3 ;desired row

ASL A ;Times 2 bytes per row (if the array's row size wasn't a multiple of 2 we'd need to actually do multiplication)

Creating an array is as simple as declaring its base address. Note that all bounds checking must be done by the programmer and is not built in by default. You also will need to have some sort of knowledge about what is stored nearby, so that you don't clobber it.

 

 

Defining an array in ROM (or RAM if you're making a program that is loaded from disk) is very simple:

MyArray:

DC.B 1,2,3,4,5

 

Strings are also arrays and most assemblers accept single or double quotes. The following are equivalent:

DC.B "Hello World",0

even

The base address can be offset by the value in a data register, to allow for assigning values to an array. The offset is always measured in bytes, so if your array is intended to contain a larger data size you will need to adjust it accordingly.

 

 

LEA myArray,A0 ;load the base address of the array into A0

 

This is the equivalent of the [[C]] code:

myArray[3] = 23;</syntaxhighlight>

 

Loading an element is very similar to storing it.

 

 

;load element 4

Inserting an element at a desired position is a bit more tricky. First of all, an array has no "end" in hardware. So how do you know where to stop? For this example, assume this array is currently contains 6 total elements (0,1,2,3,4,5) and we want to extend it.

 

 

;insert a new element into the 2nd slot and push everything behind it back.

<li>In external RAM - element retrieval/altering is most efficiently done sequentially, necessary for large arrays or peripherals</ul>

Dynamic (resizable) arrays are possible to implement, but are error-prone since bounds checking must be done by the programmer.

myarray db 'Array' ; db = define bytes - initializes 5 bytes with values 41, 72, 72, etc. (the ascii characters A,r,r,a,y)

myarray2 dw 'A','r','r','a','y' ; dw = define words - initializes 5 words (1 word = 2 bytes) with values 41 00 , 72 00, 72 00, etc.

 

Arrays are declared using JSON syntax, and are dynamic (but not sparse)

[ 1 , 2 ,3 ] \ an array holding three numbers

1 a:@ \ this will be '2', the element at index 1

=={{header|AArch64 Assembly}}==

{{works with|as|Raspberry Pi 3B version Buster 64 bits}}

/* ARM assembly AARCH64 Raspberry PI 3B */

/* program areaString64.s */

=={{header|ABAP}}==

There are no real arrays in ABAP but a construct called internal tables.

TYPES: tty_int TYPE STANDARD TABLE OF i

WITH NON-UNIQUE DEFAULT KEY.

 

=={{header|ACL2}}==

(assign array-example

(compress1 'array-example

 

=={{header|Action!}}==

BYTE i

 

 

=={{header|ActionScript}}==

var array1:Array = new Array(10);

//creates an array with the values 1, 2

 

=={{header|Ada}}==

 

A, B : array (1..20) of Integer;

=={{header|Aikido}}==

Aikido arrays (or vectors) are dynamic and not fixed in size. They can hold a set of any defined value.

var arr1 = [1,2,3,4] // initialize with array literal

var arr2 = new [10] // empty array of 10 elements (each element has value none)

=={{header|Aime}}==

The aime ''list'' is a heterogeneous, dynamic sequence. No special creation procedure, only declaration is needed:

Values (numbers, strings, collections, functions, etc) can be added in a type generic fashion:

l_append(l, "arrays");

l_append(l, pow);</syntaxhighlight>

The insertion position can be specified:

l_push(l, 4, __type(l));</syntaxhighlight>

More aptly, values (of selected types) can be inserted in a type specific fashion:

l_p_real(l, 6, 88);</syntaxhighlight>

Similarly, values can be retrieved in a type generic fashion:

or is type specific fashion:

l_q_text(l, 1);</syntaxhighlight>

 

=={{header|ALGOL 60}}==

{{trans|Simula}}

comment arrays - Algol 60;

 

 

=={{header|ALGOL 68}}==

(

[1:20]INT a;

 

=={{header|ALGOL W}}==

% declare an array %

integer array a ( 1 :: 10 );

 

=={{header|AmigaE}}==

da: PTR TO CHAR,

la: PTR TO CHAR

 

=={{header|AntLang}}==

arr: <1;2;3>

 

 

=={{header|Apex}}==

array[0] = 42;

System.debug(array[0]); // Prints 42</syntaxhighlight>

Dynamic arrays can be made using <code>List</code>s. <code>List</code>s and array can be used interchangeably in Apex, e.g. any method that accepts a <code>List<String></code> will also accept a <code>String[]</code>

aList.add(5);// appends to the end of the list

aList.add(1, 6);// assigns the element at index 1

=={{header|APL}}==

Arrays in APL are one dimensional matrices, defined by seperating variables with spaces. For example:

 

=={{header|App Inventor}}==

=={{header|AppleScript}}==

AppleScript arrays are called lists:

set ints to {1, 2, 3}</syntaxhighlight>

 

Lists can contain any objects including other lists:

 

Items can be appended to the beginning or end of a list:

 

set beginning of any to false

set end of any to Wednesday

Or a new list containing the items can be created through concatenation:

 

set any to false & any & Wednesday

--> {false, 1, "foo", 2.57, missing value, {1, 2, 3}, Wednesday}</syntaxhighlight>

List indices are 1-based and negative numbers can be used to index items from the end of the list instead of from the beginning. Items can be indexed individually or by range:

 

item -1 of any --> {1, 2, 3}

items 1 thru 3 of any --> {1, "foo", 2.57}</syntaxhighlight>

If required, items can be specified by class instead of the generic 'item' …

 

number 2 of any -- 2.57 (ie. the second number in the list)</syntaxhighlight>

 

… and some fairly complex range specifiers are possible:

 

integers from text 1 to list 1 of any --> {5, 4, 38}</syntaxhighlight>

 

The length of a list can be determined in any of three ways, although only the first two below are now recommended:

 

length of any -- Property.

number of any -- Property.</syntaxhighlight>

The number of items of a specific class can also be obtained:

 

length of any's integers</syntaxhighlight>

 

Through AppleScriptObjC, AppleScript is also able to make use of Objective-C arrays and many of their methods, with bridging possible between lists and NSArrays:

 

use framework "Foundation" -- Allows access to NSArrays and other Foundation classes.

 

=={{header|Argile}}==

{{works with|Argile|1.0.0}}

(:::::::::::::::::

 

{{works with|Argile|1.1.0}}

let x = @["foo" "bar" "123"]

print x[2]

=={{header|ARM Assembly}}==

{{works with|as|Raspberry Pi}}

/* ARM assembly Raspberry PI */

/* program areaString.s */

 

=={{header|Arturo}}==

arrA: []

{{works with|AutoHotkey_L}}

The current, official build of AutoHotkey is called AutoHotkey_L. In it, arrays are called Objects, and associative/index based work hand-in-hand.

myArray[1] := "foo"

myArray[2] := "bar"

However, variable names could be concatenated, simulating associative arrays.

By convention, based on built-in function stringsplit, indexes are 1-based and "0" index is the length.

arrayX1 = first

arrayX2 = second

=={{header|AutoIt}}==

Create an userdefined array.

#include <Array.au3> ;Include extended Array functions (_ArrayDisplay)

 

=={{header|Avail}}==

Avail supports tuples as its primary ordered collection.

 

Tuple indices (officially referred to as "subscripts") are 1-based. One can provide an alternative if there is no element at a subscript using an else clause.

<3, 2, 1>[100] else [0]</syntaxhighlight>

 

Tuples are immutable, however one can quickly create a new tuple with a specified element replaced.

 

=={{header|AWK}}==

An ordered array just uses subscripts as integers. Array subscripts can start at 1, or any other integer. The built-in split() function makes arrays that start at 1.

 

# to make an array, assign elements to it

array[1] = "first"

 

=={{header|Axe}}==

2→{L₁+1}

3→{L₁+2}

There are two kinds of array in Babel: value-arrays and pointer-arrays. A value-array is a flat array of data words. A pointer-array is an array of pointers to other things (including value-arrays). You can create a data-array with plain square-brackets. You can create a value-array with the [ptr ] list form:

 

 

 

 

===Get a single array element===

 

 

{{Out}}

Changing a value-array element:

 

</syntaxhighlight>

 

Changing a pointer-array element:

 

 

{{Out}}

===Select a range of an array===

 

 

{{Out}}

You can concatenate arrays of same type:

 

 

 

Concatenation creates a new array - it does not add to an array in-place. Instead, Babel provides operators and standard utilities for converting an array to a list in order to manipulate it, and then convert back.

Convert a value-array to a list of values:

 

 

{{Out}}

Convert a list of values to a value-array:

 

 

{{Out}}

Convert a pointer-array to a list of pointers:

 

 

{{Out}}

Convert a list of pointers to a pointer-array:

 

 

{{Out}}

Note: We need to use quotes in DATA

 

DATA "January", "February", "March", "April", "May", "June", "July"

DATA "August", "September", "October", "November", "December"

 

2.) A modern BaCon approach to do arrays using strings

DECLARE A$[11] = {"January", "February", "March", "April", "May", \

"June", "July", "August", "September", "October", "November", "December"} TYPE STRING

name this '''split.bac'''

 

SPLIT ARGUMENT$ BY " " TO TOK$ SIZE len_array

 

in the terminal

./split January February March April May June July August September October November December

</syntaxhighlight>

 

The default array base (lower bound) can be set with OPTION BASE. If OPTION BASE is not set, the base may be either 0 or 1, depending on implementation. The value given in DIM statement is the upper bound. If the base is 0, then DIM a(100) will create an array containing 101 elements.

DIM myArray(100) AS INTEGER </syntaxhighlight>

 

Alternatively, the lower and upper bounds can be given while defining the array:

 

Dynamic arrays:

'$DYNAMIC

DIM SHARED myArray(-10 TO 10, 10 TO 30) AS STRING

BASIC does not generally have option for initializing arrays to other values, so the initializing is usually done at run time.

DATA and READ statements are often used for this purpose:

DATA January, February, March, April, May, June, July

DATA August, September, October, November, December

 

FreeBASIC has an option to initialize array while declaring it.

 

20 REM ELEMENT NUMBERS TRADITIONALLY START AT ONE

30 DIM A%(11): REM ARRAY OF ELEVEN INTEGER ELEMENTS

===Static===

 

 

staticArray(0) = -1

Note that BASIC dynamic arrays are not stack-based; instead, their size must be changed in the same manner as their initial declaration -- the only difference between static and dynamic arrays is the keyword used to declare them (<code>DIM</code> vs. <code>REDIM</code>). [[QBasic]] lacks the <code>PRESERVE</code> keyword found in some modern BASICs; resizing an array without <code>PRESERVE</code> zeros the values.

 

 

dynamicArray(0) = -1

 

==={{header|Applesoft BASIC}}===

20 LET A%(0) = -1

30 LET A%(11) = 1

 

=={{header|BASIC256}}==

dim numbers(10)

for t = 0 to 9

Arrays can be approximated, in a style similar to REXX

 

@echo off

setlocal ENABLEDELAYEDEXPANSION

 

=={{header|BBC BASIC}}==

DIM array(6), array%(6), array$(6)

 

The following is a transcript of an interactive session:

g[3] = 42

/* Look at some other elements in g */

'''Note:''' Variables in BML can either be placed in a prefix group($, @, and &) or in the world. Placing variables in the world is not recommended since it can take large sums of memory when using said variable.

 

% Define an array(containing the numbers 1-3) named arr in the group $

in $ let arr hold 1 2 3

 

=={{header|Boo}}==

myArray as (int) = (1, 2, 3) // Size based on initialization

fixedArray as (int) = array(int, 1) // Given size(1 in this case)

 

All arrays are variable length, and can contain any types of values.

arr ← 1‿2‿'a'‿+‿5

# General List Syntax:

# Modifying the array(↩):

arr ↩ "hello"⌾(4⊸⊑) arr</syntaxhighlight>

⟨ 1 2 'a' + 5 ⟩

⟨ 1 2 'a' + 5 ⟩

To delete and array (and therefore the variable with the array's name), call <code>tbl</code> with a size <code>0</code>.

 

& 5:?(30$mytable)

& 9:?(31$mytable)

Note that Brainf*** does not natively support arrays, this example creates something that's pretty close, with access of elements at each index, altering elements, and changing size of list at runtime.

 

===========[

ARRAY DATA STRUCTURE

=={{header|C}}==

Fixed size static array of integers with initialization:

float myFloats[] ={1.2, 2.5, 3.333, 4.92, 11.2, 22.0 }; /* automatically sizes */</syntaxhighlight>

 

When no size is given, the array is automatically sized. Typically this is how initialized arrays are defined. When this is done, you'll often see a definition that produces the number of elements in the array, as follows.

 

When defining autosized multidimensional arrays, all the dimensions except the first (leftmost) need to be defined. This is required in order for the compiler to generate the proper indexing for the array.

float my2Dfloats[][3] = {

1.0, 2.0, 0.0,

When the size of the array is not known at compile time, arrays may be dynamically

allocated to the proper size. The <code>malloc()</code>, <code>calloc()</code> and <code>free()</code> functions require the header <code>stdlib.h</code>.

int *myArray = malloc(sizeof(int) * numElements); /* array of 10 integers */

if ( myArray != NULL ) /* check to ensure allocation succeeded. */

 

The first element of a C array is indexed with 0. To set a value:

myArray[1] = 3;</syntaxhighlight>

 

And to retrieve it (e.g. for printing, provided that the <tt>stdio.h</tt> header was included for the printf function)

 

The <tt>array[index]</tt> syntax can be considered as a shortcut for <tt>*(index + array)</tt> and

thus the square brackets are a commutative binary operator:

printf("%d\n", *(array + index));

3[array] = 5;</syntaxhighlight>

 

There's no bounds check on the indexes. Negative indexing can be implemented as in the following.

double *kernel = malloc(sizeof(double)*2*XSIZE+1);

if (kernel) {

Typically dynamic allocation is used and the allocated array is sized to the maximum that might be needed. A additional variable is

declared and used to maintain the current number of elements used. In C, arrays may be dynamically resized if they were allocated:

int *array = malloc (sizeof(int) * 20);

....

</syntaxhighlight>

A Linked List for chars may be implemented like this:

#include <stdlib.h>

#include <stdio.h>

Example of array of 10 int types:

 

 

Example of array of 3 string types:

 

 

You can also declare the size of the array and initialize the values at the same time:

 

 

 

 

The following creates a 3x2 int matrix

 

As with the previous examples you can also initialize the values of the array, the only difference being each row in the matrix must be enclosed in its own braces.

 

 

or

 

 

 

array[0] = 1;

Dynamic

 

using System.Collections.Generic;

 

<code>std::vector<T></code> is a resizable array of <code>T</code> objects.

The memory for the array will be allocated from the heap (unless a custom allocator is used).

#include <vector>

 

=={{header|Ceylon}}==

{{works with|Ceylon|1.3.0}}

 

ArrayList

 

=={{header|ChucK}}==

int array[0]; // instantiate int array

array << 1; // append item

===Lazy array===

Create a lazy array of strings using an array denotation.

array = {"Hello", "World"}</syntaxhighlight>

Create a lazy array of floating point values by sharing a single element.

array = createArray 10 3.1415</syntaxhighlight>

Create a lazy array of integers using an array (and also a list) comprehension.

array = {x \\ x <- [1 .. 10]}</syntaxhighlight>

===Strict array===

Create a strict array of integers.

array = {x \\ x <- [1 .. 10]}</syntaxhighlight>

===Unboxed array===

Create an unboxed array of characters, also known as <tt>String</tt>.

array = {x \\ x <- ['a' .. 'z']}</syntaxhighlight>

 

=={{header|Clipper}}==

Clipper arrays aren't divided to fixed-length and dynamic. Even if we declare it with a certain dimensions, it can be resized in the same way as it was created dynamically. The first position in an array is 1, not 0, as in some other languages.

Local arr1 := { { "NITEM","N",10,0 }, { "CONTENT","C",60,0} }

// Create an empty array

arr4 := ASize( arr4, 80 )</syntaxhighlight>

Items, including nested arrays, can be added to existing array, deleted from it, assigned to it

Aadd( arr1, { "LBASE","L",1,0 } )

// Delete the first item of arr3, The size of arr3 remains the same, all items are shifted to one position, the last item is replaced by Nil:

arr3[1,1,1] := 11.4</syntaxhighlight>

Retrieve items of an array:

// The retrieved item can be nested array, in this case it isn't copied, the pointer to it is assigned

</syntaxhighlight>

There is a set of functions to manage arrays in Clipper, including the following:

AFill( arr4, 0, 5, 20 )

//Copy 10 items from arr4 to arr3[2], starting from the first position:

 

=={{header|Clojure}}==

;is, instead clojure creates a new array with an added value using (conj...)

;in the example below the my-list does not change.

=={{header|COBOL}}==

In COBOL, arrays are called ''tables''. Also, indexes begin from 1.

PROGRAM-ID. arrays.

 

 

=={{header|CoffeeScript}}==

array1[0] = "Dillenidae"

array1[1] = "animus"

=={{header|ColdFusion}}==

Creating a one-dimensional Array:

 

Creating a two-dimensional Array in CFScript:

arr2 = ArrayNew(2);

</cfscript></syntaxhighlight>

=={{header|Common Lisp}}==

 

(setf (aref array 0) 1

(aref array 1) 3)

Dynamic

 

(vector-push-extend 1 array)

(vector-push-extend 3 array)

 

Creates a one-dimensional array of length 10. The initial contents are undefined.

Creates a two-dimensional array with dimensions 10x20.

<tt>make-array</tt> may be called with a number of optional arguments.

(make-array 20 :initial-element nil)

; Makes an integer array of 4 elements containing 1 2 3 and 4 initially which can be resized

 

 

MODULE TestArray;

(* Implemented in BlackBox Component Builder *)

===Fixed-length array===

We have finished iterating through the array when the next load instruction would be <tt>LDA ary+length(ary)</tt>.

ADD sum

STA sum

10</syntaxhighlight>

===Zero-terminated array===

BRZ done

 

 

=={{header|Crystal}}==

# create an array with one object in it

a = ["foo"]

 

=={{header|D}}==

 

import std.stdio, core.stdc.stdlib;

D) Element 1: 3</pre>

One more kind of built-in array:

 

void main() {

 

=={{header|Dao}}==

a = [ 1, 2, 3 ] # a vector

b = [ 1, 2; 3, 4 ] # a 2X2 matrix

 

=={{header|Dart}}==

main(){

// Dart uses Lists which dynamically resize by default

 

=={{header|DBL}}==

; Arrays for DBL version 4 by Dario B.

;

=={{header|Delphi}}==

This example creates a static and dynamic array, asks for a series of numbers storing them in the static one, puts in the dynamic one the numbers in reverse order, concatenates the number in two single string variables and display those strings in a popup window.

procedure TForm1.Button1Click(Sender: TObject);

var

 

=={{header|Diego}}==

set_base(0);

 

 

=={{header|Dragon}}==

array[0] = 42

showln array[2] </syntaxhighlight>

=={{header|DWScript}}==

 

// dynamic array, extensible, this a reference type

var d : array of Integer;

=={{header|Dyalect}}==

 

var empty = []

var xs = [1, 2, 3]

=={{header|Déjà Vu}}==

In Déjà Vu, the relevant datatype is called list, which is basically a stack with random element access for getting and setting values.

local :l []

 

Literal lists are <code>ConstList</code>s.

 

# value: []

 

Note that each of these operations returns a different list object rather than modifying the original. You can, for example, collect values:

 

# value: []

 

FlexLists can be created explicitly, but are typically created by ''diverging'' another list. A ConstList can be gotten from a FlexList by ''snapshot''.

 

# value: [1, 2].diverge()

 

Creating a FlexList with a specific size, generic initial data, and a type restriction:

 

 

Note that this puts the same value in every element; if you want a collection of some distinct mutable objects, see [[N distinct objects#E]].

=={{header|EasyLang}}==

 

for i range len f[]

f[i] = i

 

'''Fixed-length array'''

array int[10]; //optionally, add a braced list of values. E.g. array int[10]{1, 2, 3};

array[1] = 42;

 

=={{header|Eiffel}}==

class

APPLICATION

 

Static array

Generic array

array[0] := 1;

array[1] := 2;

array[2] := 3;</syntaxhighlight>

Stack allocated array

stackAllocatedArray[0] := 1;

stackAllocatedArray[1] := 2;

stackAllocatedArray[2] := 3;</syntaxhighlight>

Dynamic array

dynamicArray.append:1;

dynamicArray.append:2;

dynamicArray[2] := 3;</syntaxhighlight>

Printing an element

system'console.writeLine(stackAllocatedArray[1]);

system'console.writeLine(dynamicArray[2]);</syntaxhighlight>

The elixir language has array-like structures called ''tuples''. The values of tuples occur sequentially in memory, and can be of any type. Tuples are represented with curly braces:

 

 

Elements of tuples are indexed numerically, starting with zero.

 

elem(ret, 0) == :ok

put_elem(ret, 2, "pi") # => {:ok, "fun", "pi"}

Elements can be appended to tuples with <tt>Tuple.append/2</tt>, which returns a new tuple, without having modified the tuple given as an argument.

 

 

New tuple elements can be inserted with <tt>Tuple.insert/3</tt>, which returns a new tuple with the given value inserted at the indicated position in the tuple argument.

 

 

Elixir also has structures called ''lists'', which can contain values of any type, and are implemented as linked lists. Lists are represented with square brackets:

 

 

Lists can be indexed, appended, added, subtracted, and list elements can be replaced, updated, and deleted. In all cases, new lists are returned without affecting the list being operated on.

 

my_list ++ [4, :five] # => [1, :two, "three", 4, :five]

 

Lists have a ''head'', being the first element, and a ''tail'', which are all the elements of the list following the head.

 

[:apple, :banana, :cherry]

iex(2)> hd(fruit)

 

=={{header|Erlang}}==

%% Create a fixed-size array with entries 0-9 set to 'undefined'

A0 = array:new(10).

 

=={{header|Euphoria}}==

--Arrays task for Rosetta Code wiki

--User:Lnettnay

=={{header|F Sharp|F#}}==

'''Fixed-length arrays:'''

val it : char [] = [|'A'; 'A'; 'A'; 'A'; 'A'; 'A'|]

> Array.init 8 (fun i -> i * 10) ;;

 

If dynamic arrays are needed, it is possible to use the .NET class <code>System.Collections.Generic.List<'T></code> which is aliased as <code>Microsoft.FSharp.Collections.ResizeArray<'T></code>:

val arr : ResizeArray<int>

> arr.Add(42);;

 

Directly in the listener :

{

[ "The initial array: " write . ]

{ 1 "coucou" f [ ] }

Arrays of growable length are called Vectors.

{

[ "The initial vector: " write . ]

For example, a static array of 10 cells in the dictionary, 5 initialized and 5 uninitialized:

 

here constant MyArrayEnd

 

: .array MyArrayEnd MyArray do I @ . cell +loop ;</syntaxhighlight>

 

: array ( n -- )

create

.MyArray \ 1 2 3 4 5 0 30 0 0 0

</syntaxhighlight>

: array create dup , dup cells here swap 0 fill cells allot ;

: [size] @ ;

 

Basic array declaration:

Arrays are one-based. These declarations are equivalent:

Other bases can be used:

Arrays can have any type (intrinsic or user-defined), e.g.:

Multidimensional array declaration:

Allocatable array declaration:

Array allocation:

Array deallocation:

Array initialisation:

integer, dimension (10) :: a = (/(i * i, i = 1, 10)/)</syntaxhighlight>

integer, dimension (10, 10) :: a = reshape ((/(i * i, i = 1, 100)/), (/10, 10/))</syntaxhighlight>

Constant array declaration:

integer, dimension (10), parameter :: a = (/(i * i, i = 1, 10)/)</syntaxhighlight>

Element assignment:

Array assignment (note that since Fortran 2003 array assignment also allocates or reallocates if necessary):

Array section assignment:

Element retrieval:

Array section retrieval:

Size retrieval:

Size along a single dimension retrieval:

Bounds retrieval:

Bounds of a multidimensional array retrieval:

 

=={{header|FreeBASIC}}==

 

'''The default lower bound is always 0'''

' compile with: FBC -s console -exx to have boundary checks.

 

=={{header|Frink}}==

In Frink, all arrays are dynamically resizable. Arrays can be created as literals or using <CODE>new array</CODE>

a = new array

a@0 = 10

Multidimensional regular arrays are a built-in datatype in Futhark. They can be written as array literals:

 

[1, 2, 3]

</syntaxhighlight>

Or created by an assortment of built-in functions:

 

replicate 5 3 == [3,3,3,3,3]

iota 5 = [0,1,2,3,4]

Uniqueness types are used to permit in-place updates without violating referential transparency. For example, we can write a function that writes an element to a specific index of an array as such:

 

fun update(as: *[]int, i: int, x: int): []int =

let as[i] = x

In Gambas, there is no need to dimension arrays. The first element of an array is numbered zero, and the DIM statement is optional and can be omitted:

 

DIM mynumbers AS INTEGER[]

myfruits AS STRING[]

 

'''[https://gambas-playground.proko.eu/?gist=5061d7f882a4768d212080e416c25e27 Click this link to run this code]'''

Dim sFixedArray As String[] = ["Rosetta", "code", "is", "a", "programming", "chrestomathy", "site"]

Dim sFixedArray1 As New String[10]

 

=={{header|GAP}}==

v := [ 10, 7, "bob", true, [ "inner", 5 ] ];

# [ 10, 7, "bob", true, [ "inner", 5 ] ]

 

=={{header|Genie}}==

/*

Arrays, in Genie

====Example of Fixed Length Array====

Array containing a space (" "), "A", "B", and "C":

array[1] = 'A'

array[2] = 'B'

====Example of Arbitrary Length Array====

Array containing the set of all natural numbers from 1 through k:

array[i] = i + 1</syntaxhighlight>

 

====Example of Fixed Length Array====

Array containing the multiplication table of 1 through 4 by 1 through 3:

array[1,2] = 2

array[1,3] = 3

====Example of Arbitrary Length Array====

Array containing the multiplication table of 1 through k by 1 through h:

for(j = 1; j <= h; j += 1)

array[i,j] = i * j</syntaxhighlight>

 

=={{header|Go}}==

 

import (

In Golfscript, arrays are created writing their elements between []. Arrays can contain any kind of object. Once created, they are pushed on the stack, as any other object.

 

10,:a; # assign to a [0 1 2 3 4 5 6 7 8 9]

a 0= puts # pick element at index 0 (stack: 0)

=={{header|Groovy}}==

Arrays and lists are synonymous in Groovy. They can be initialized with a wide range of operations and Groovy enhancements to the Collection and List classes.

def a = [0] * 100 // list of 100 zeroes

def b = 1..9 // range notation

 

Here is a more interesting example showing a function that creates and returns a square identity matrix of order N:

(1..n).collect { i -> (1..n).collect { j -> i==j ? 1.0 : 0.0 } }

}</syntaxhighlight>

 

Test program:

def i15 = identity(15)

 

Groovy, like every other C-derived language in the known universe, uses ZERO-based array/list indexing.

 

 

println strings

Negative indices are valid. They indicate indexing from the end of the list towards the start.

 

 

{{out}}

Groovy lists can be resequenced and subsequenced by providing lists or ranges of indices in place of a single index.

 

println strings[0..4]

println strings[0..3, -5]</syntaxhighlight>

Graphical User Interface Support Script does not have variables or array storage of its own. However, it can make use of installed applications, so it is possible to utilize an installed spreadsheet application to create and manipulate arrays. Here we assume that a spreadsheet is installed and create an array containing three names:

 

 

=={{header|GW-BASIC}}==

(GW-BASIC User's Guide)

 

20 DIM A(9) ' Array with size 10 (9 is maximum subscript), all elements are set to 0

30 FOR I = 0 TO 9

 

=={{header|Halon}}==

$array[] = 1;

=={{header|Harbour}}==

Harbour arrays aren't divided to fixed-length and dynamic. Even if we declare it with a certain dimensions, it can be resized in the same way as it was created dynamically. The first position in an array is 1, not 0, as in some other languages.

local arr1 := { { "NITEM", "N", 10, 0 }, { "CONTENT", "C", 60, 0 } }

// Create an empty array

arr4 := ASize( arr4, 80 )</syntaxhighlight>

Items, including nested arrays, can be added to existing array, deleted from it, assigned to it

AAdd( arr1, { "LBASE", "L", 1, 0 } )

// Delete the first item of arr3, The size of arr3 remains the same, all items are shifted to one position, the last item is replaced by Nil:

arr3[ 1, 1, 1 ] := 11.4</syntaxhighlight>

Retrieve items of an array:

// The retrieved item can be nested array, in this case it isn't copied, the pointer to it is assigned

</syntaxhighlight>

There is a set of functions to manage arrays in Clipper, including the following:

AFill( arr4, 0, 5, 20 )

// Copy 10 items from arr4 to arr3[ 2 ], starting from the first position:

=={{header|Haskell}}==

You can read all about Haskell arrays [http://haskell.org/haskellwiki/Arrays here]. The following example is taken from that page:

 

main = do arr <- newArray (1,10) 37 :: IO (IOArray Int Int)

 

=={{header|hexiscript}}==

let a[0] 123 # index starting at 0

let a[1] "test" # can hold different types

 

=={{header|HicEst}}==

 

Astat(2) = 2.22222222

 

=={{header|HolyC}}==

U8 array[10] = 1, 2, 3, 4, 5, 6, 7, 8, 9, 10;

 

==Icon and Unicon==

==={{header|Icon}}===

 

procedure main()

==={{header|Unicon}}===

This Icon solution works in Unicon.

# insert and delete work on lists allowing changes in the middle

# possibly others

 

=={{header|i}}==

//Fixed-length arrays.

f $= array.integer[1]()

 

=={{header|Io}}==

foo at(1) println // bar

foo append("Foobarbaz")

=={{header|J}}==

In J, all data occurs in the form of rectangular (or generally [[wp:Hyperrectangle|orthotopic]]) arrays. This is true for both named and anonymous data.

1

NB. invoking any array produces that array as the result

Note also that J's arrays are (with some obscure exceptions) "constants". We can append to an existing array, creating a new array, but if we kept a reference to the original it would have remained unchanged.

 

B=: A, 9 5

B

7 11</syntaxhighlight>

 

B=: A_:, 1 3 9 5

B

 

=={{header|Java}}==

array[0] = 42;

System.out.println(array[3]);</syntaxhighlight>

Dynamic arrays can be made using <code>List</code>s:

 

list.add(5); // appends to the end of the list

list.add(1, 6); // inserts an element at index 1

JavaScript arrays are Objects that inherit from Array prototype and have a special length property that is always one higher than the highest non–negative integer index. Methods inherited from Array.prototype are mostly generic and can be applied to other objects with a suitable length property and numeric property names.

Note that if the Array constructor is provided with one argument, it is treated as specifying the length of the new array, if more than one argument is supplied, they are treated as members of the new array.

var myArray = new Array();

 

jq arrays have the same syntax as JSON arrays, and there are similarities with Javascript arrays. For example, the index origin is 0; and if a is an array and if n is an integer less than the array's length, then a[n] is the n-th element. The length of any array, a, can be ascertained using the length filter: a|length.

 

[]

 

=={{header|Jsish}}==

From Javascript, with the differences that Jsi treats ''typeof [elements]'' as "array", not "object".

// Create a new array with length 0

var myArray = new Array();

 

=={{header|KonsolScript}}==

Array:New array[3]:Number;

 

 

=={{header|Kotlin}}==

var a = arrayOf(1, 2, 3, 4)

println(a.asList())

 

=={{header|Lambdatalk}}==

// Create a new array with length 0

{def myArray1 {A.new}}

 

=={{header|lang5}}==

1 append

['foo 'bar] append

Langur uses 1-based indexing.

 

val .a2 = series 4..10

val .a3 = .a1 ~ .a2

Lasso Array [http://lassoguide.com/operations/containers.html?#array] objects store zero or more elements and provide random access to those elements by position. Positions are 1-based integers. Lasso Arrays will grow as needed to accommodate new elements. Elements can be inserted and removed from arrays at any position. However, inserting an element anywhere but at the end of an array results in all subsequent elements being moved down.

 

local(array1) = array

Lasso also supports Static Arrays[http://lassoguide.com/operations/containers.html#staticarray]. A Lasso staticarray is a container object that is not resizable. Staticarrays are created with a fixed size. Objects can be reassigned within the staticarray, but new positions cannot be added or removed.

 

local(mystaticArray) = staticarray('a','b','c','d','e')

 

 

Like everything in Latitude, arrays are simply objects. In particular, arrays store their elements in numerical slots rather than traditional symbolic ones. The translation scheme used to store them enables constant-time push and pop operations on either side of the array.

foo := [1, 2, 3].

 

 

Using the LFE REPL, you can explore arrays in the following manner:

; Create a fixed-size array with entries 0-9 set to 'undefined'

> (set a0 (: array new 10))

DATA is READ into variables. It cannot be READ directly into arrays.

<br>To fill arrays with DATA items, first READ the item into a variable, then use that variable to fill an index of the array.

dim Array(10)

 

For filter and foreach, the VARNAME fields are optional, LIL creates defaults inside the code block of '''x''' for filter and '''i''' for foreach if user names are not given.

 

set a [list abc def ghi]

set b [list 4 5 6]

 

=={{header|Lingo}}==

put a[2] -- or: put a.getAt(2)

-- 2

In addition to the 'list' type shown above, for arrays of bytes (i.e. integers between 0 and 255) there is also the bytearray data type:

 

put ba

-- <ByteArrayObject length = 2 ByteArray = 0xff, 0xff >

 

=={{header|Lisaac}}==

a := ARRAY(INTEGER).create 0 to 9;

a.put 1 to 0;

=={{header|Little}}==

Arrays in Little are list of values of the same type and they grow dynamically.

 

They are zero-indexed. You can use END to get the last element of an array:

puts(fruit[0]);

puts(fruit[1]);

 

=={{header|Logo}}==

(array 5 0) ; custom origin

make "a {1 2 3 4 5} ; array literal

 

=={{header|LOLCODE}}==

BTW declaring array

I HAS A array ITZ A BUKKIT

 

=={{header|LSE64}}==

0 array 5 [] ! # store 0 at the sixth cell in the array

array 5 [] @ # contents of sixth cell in array</syntaxhighlight>

=={{header|LSL}}==

LSL does not have Arrays, but it does have [http://wiki.secondlife.com/wiki/List lists] which can function similar to a one dimensional ArrayList in Java or C#.

default {

state_entry() {

=={{header|Lua}}==

Lua does not differentiate between arrays, lists, sets, dictionaries, maps, etc. It supports only one container: Table. Using Lua's simple yet powerful syntax, any of these containers can be emulated. All tables are dynamic. If a static array is necessary, that behavior can be created.

l[1] = 1 -- Index starts with 1, not 0.

l[0] = 'zero' -- But you can use 0 if you want

We can copy multiple items from an array to another array (ore the same) with statement Stock. We can copy from memory to strings and place them to other address.

 

Module CheckArray {

\\ Array with parenthesis in name

===Passing Arrays By Reference===

By default arrays passed by value. Here in make() we read reference in a variable A, which interpreter put then pointer to array, so it is a kind of reference (like in C). Using & we have normal reference. A ++ operator in a pointer of array add one to each element.

Dim a(10)=1

Print a() ' 1 1 1 1 1 1 1 1 1 1

 

=={{header|Maple}}==

a := Array (1..5);

a := [ 0 0 0 0 0 ]

 

=={{header|Mathematica}} / {{header|Wolfram Language}}==

a[[1]]

Delete[a, 2]</syntaxhighlight>

Variables are not typed until they are initialized. So, if you want to create an array you simply assign a variable name the value of an array. Also, memory is managed by MATLAB so an array can be expanded, resized, and have elements deleted without the user dealing with memory. Array elements can be retrieved in two ways. The first way is to input the row and column indicies of the desired elements. The second way is to input the subscript of the array elements.

 

 

a =

 

=={{header|Maxima}}==

array(a, flonum, 20, 20, 3)$

 

Mercury's arrays are a mutable non-functional type, and therefore are slightly more troublesome than functional types to A) accept as parameters to predicates, and B) involve in higher-order code, and C) include as a member of a composite data type. All of this is still very possible, but it requires an understanding of Mercury's variable instantiation system, as you can't just have 'in' and 'out' modes for parameters that involve arrays. Mercury has a 'bt_array' module with performance characteristics very similar to that of arrays, but which is a functional type and therefore is easier to work with. Especially if you're just starting out with Mercury, going with bt_array can be a big win for 'whippitupitude'.

 

:- interface.

:- import_module io.

 

Example:

print arr[0]

 

 

=={{header|MIPS Assembly}}==

.data

array: .word 1, 2, 3, 4, 5, 6, 7, 8, 9 # creates an array of 9 32 Bit words.

 

=={{header|Modula-3}}==

Defines a static array of 10 elements, indexed 1 through 10.

 

Static arrays can also be given initial values:

VAR staticArray2 := ARRAY [1..10] OF INTEGER {1, ..} (* Initialize all elements to 1. *)</syntaxhighlight>

 

Open (dynamic) arrays can be be defined by creating a reference to an array of an unspecified size:

VAR openArray: TOpenIntArray;</syntaxhighlight>

Defines an open array of a currently unknown size.

Open arrays must first be initialized via a call to the built-in function NEW, passing in the type and the size of the array.

The allocation is performed on the heap and all elements are initialized to 0:

Initializes the open array to hold 10 elements, indexed 0 through 9. Modula-3 uses garbage collection for heap allocated data by default, so once all references to the open array go out of scope, the memory it occupied is de-allocated automatically.

 

Retrieval or insertion of elements and determining array bounds is performed using the same built-in functions regardless of the array kind. Though open arrays must first be de-referenced when passing them to such functions. Assuming we have made the declarations above, we can do the following:

staticArraySize := NUMBER(staticArray);

staticArrayElement := staticArray[4];

openArrayElement := openArray[9];</syntaxhighlight>

 

openArray[1] := 200;</syntaxhighlight>

 

=={{header|Monte}}==

 

 

To retrieve a value:

 

 

To change a value:

 

 

Now myArray is ['a','b','c','z'].

 

=={{header|Nanoquery}}==

arr = array(10)

 

 

=={{header|Neko}}==

 

$print(myArray[0]);</syntaxhighlight>

 

=={{header|Nemerle}}==

using System.Console;

using System.Collections;

=={{header|NetRexx}}==

'''Note:''' Dynamic arrays can be simulated via the [[Java]] [http://download.oracle.com/javase/6/docs/technotes/guides/collections/index.html Collections Framework] or by using [[NetRexx]] ''indexed strings'' (AKA: [[Creating an Associative Array|associative arrays]]).

options replace format comments java crossref symbols nobinary

 

=={{header|NewLISP}}==

This creates an array of 5 elements, initialized to <code>nil</code>:

→ (nil nil nil nil nil)</syntaxhighlight>

The example below creates a multi-dimensional array (a 3-element array of 4-element arrays), initialized using the values returned by the function sequence (a list containing whole numbers from 1 to 12) and stores the newly created array in a variable called myarray. The return value of the set function is the array.

→ ((1 2 3 4) (5 6 7 8) (9 10 11 12))</syntaxhighlight>

 

=={{header|Nim}}==

x = [1,2,3,4,5,6,7,8,9,10] # type and size automatically inferred

y: array[1..5, int] = [1,2,3,4,5] # starts at 1 instead of 0

 

=={{header|NS-HUBASIC}}==

20 A(1)=10

30 PRINT A(1)</syntaxhighlight>

NSIS does not have native support for arrays. Array support is provided by the [http://nsis.sourceforge.net/Arrays_in_NSIS NSISArray] plugin.

</div>

!include NSISArray.nsh

Function ArrayTest

 

=={{header|Oberon-2}}==

MODULE Arrays;

IMPORT

 

=={{header|Objeck}}==

bundle Default {

class Arithmetic {

 

=={{header|Objective-C}}==

 

// Create an array of NSString objects.

=={{header|OCaml}}==

in the toplevel:

- : char array = [|'A'; 'A'; 'A'; 'A'; 'A'; 'A'|]

 

To create a mutable array, #new is used.

 

 

Array new dup addAll( [1, 2, 3] ) dup put( 2, 8.1 ) .

The last element in a vector is indexed by minus one, and the first element is indexed by minus length of the vector.

 

; making a vector

> #(1 2 3 4 5)

=={{header|ooRexx}}==

ooRexx arrays hold object references. Arrays will automatically increase in size if needed.

b = .array~new(10) -- create an array with initial size of 10

c = .array~of(1, 2, 3) -- create a 3 element array holding objects 1, 2, and 3

to all compound variables with that stem.

 

XXX.='*'

Say 'xxx.1='xxx.1 -- shows xxx.1=*

must not exceed 250 bytes no longer applies to ooRexx and Regina.

XXX.u.v...='something'

v='John Doe'

XXX.u.v...='some value'

 

When using a stem for storing structured data, as in

person.last='Pachl'</syntaxhighlight>

it is advisable to use constant symbols such as 0first and 0last in the tail

 

=={{header|OxygenBasic}}==

 

'CREATING A STATIC ARRAY

=={{header|Oz}}==

 

Arr = {Array.new 1 %% lowest index

10 %% highest index

 

=={{header|PARI/GP}}==

v=concat(v,7);

v[1]</syntaxhighlight>

=={{header|Pascal}}==

A modification of the Delphi example:

Program ArrayDemo;

uses

In-line

 

my @empty_too = ();

Dynamic

 

 

push @arr, 1;

Two-dimensional

 

[0, 1, 2, 3],

[qw(a b c d e f g)],

without any need to worry about memory management issues.

 

<span style="color: #000080;font-style:italic;">-- simple one-dimensional arrays:</span>

<span style="color: #004080;">sequence</span> <span style="color: #000000;">s1</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">0.5</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">1</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">4.7</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">9</span><span style="color: #0000FF;">},</span> <span style="color: #000080;font-style:italic;">-- length(s1) is now 4</span>

 

=={{header|Phixmonti}}==

 

0 tolist /# create an empty array/list. '( )' is equivalent #/

===Writing To An Array===

====Single Dimension====

$LetterArray = array("a", "b", "c", "d", "e", "f");

$simpleForm = ['apple', 'orange'];</syntaxhighlight>

 

====Multi-Dimensional====

array(0, 0, 0, 0, 0, 0),

array(1, 1, 1, 1, 1, 1),

====Array push====

 

array_push($arr, 'pear');

print implode(',', $arr); // Returns apple,orange,pear</syntaxhighlight>

====Single Dimension====

Read the 5th value in the array:

echo $LetterArray[5]; // Returns f</syntaxhighlight>

====Multi-Dimensional====

Read the 2nd line, column 5

===Print a whole array===

This is useful while developing to view the contents of an array:

Which would give us:

0 => array(

0 => 0

=== Set custom keys for values===

This example starts the indexing from 1 instead of 0

This example shows how you can apply any key you want

 

To read the 3rd value of the second array:

 

===Other Examples===

Create a blank array:

 

Set a value for the next key in the array:

 

Assign a value to a certain key:

 

=={{header|Picat}}==

 

Here are some examples how to use arrays.

 

go =>

 

{{trans|Prolog}}

List = new_list(5), % create a list of length 5

nth(1,List,a), % put an a at position 1 , nth/3 uses indexing from 1

=={{header|PicoLisp}}==

PicoLisp has no built-in array data type. Lists are used instead.

(mapc println A) # Show it</syntaxhighlight>

{{out}}

((d e) NIL 777)</pre>

Replace 'b' with 'B' in middle row:

(mapc println A)</syntaxhighlight>

{{out}}

((d e) NIL 777)</pre>

Insert '1' in front of the middle row:

(mapc println A)</syntaxhighlight>

{{out}}

((d e) NIL 777)</pre>

Append '9' to the middle row:

(mapc println A)</syntaxhighlight>

{{out}}

 

=={{header|Pike}}==

// Initial array, few random elements.

array arr = ({3,"hi",84.2});

 

=={{header|PL/I}}==

declare A(10) float initial (1, 9, 4, 6, 7, 2, 5, 8, 3, 10);

 

Arrays are a bit of a sticking point for Plain English, because its creators have not as yet devised a sufficiently elegant way to work with them within the constraints of the language. Only lists have high-level routine support. Nevertheless, the capability to build arrays ourselves exists within the language. Following is an example of how it could be done.

 

Start up.

Write "Creating an array of 100 numbers..." on the console.

 

Arrays are homogenous.

 

- - -

 

=={{header|PostScript}}==

%Declaring array

 

=={{header|PowerShell}}==

Empty array:

Array initialized with only one member:

$a = @(2) # alternative</syntaxhighlight>

Longer arrays can simply be created by separating the values with commas:

A value can be appended to an array using the <code>+=</code> operator:

Since arrays are immutable this simply creates a new array containing one more member.

 

Values can be retrieved using a fairly standard indexing syntax:

Similarly, those values can also be replaced:

The range operator <code>..</code> can be used to create contiguous ranges of integers as arrays:

Indexing for retrieval allows for arrays as well, the following shows a fairly complex example combining two ranges and an arbitrary array in the indexer:

Indexing from the end of the array can be done with negative numbers:

 

=={{header|Prolog}}==

retrieve and set elements.

 

singleassignment:-

functor(Array,array,100), % create a term with 100 free Variables as arguments

programming languages, setarg/3 can be used.

 

destructive:-

functor(Array,array,100), % create a term with 100 free Variables as arguments

Lists can be used as arrays.

 

listvariant:-

length(List,100), % create a list of length 100

'''Dim''' is used to create new arrays and initiate each element will be zero. An array in PureBasic can be of any types, including structured, and user defined types. Once an array is defined it can be resized with '''ReDim'''. Arrays are dynamically allocated which means than a variable or an expression can be used to size them.

 

Dim MyArray.i(22)

MyArray(0) = 7

MyArray(7) = 23</syntaxhighlight>

'''ReDim''' is used to 'resize' an already declared array while preserving its content. The new size can be both larger or smaller, but the number of dimension of the array can not be changed after initial creation.

ReDim MyArray(55)

MyArray(22) = 7

MyArray(33) = 11

MyArray(44) = 23</syntaxhighlight>

For i=0 To ArraySize(MyArray())

If MyArray(i)

EndIf

Next</syntaxhighlight>

Dim MultiArray.i(800, 600)

MultiArray(100, 200) = 640

MultiArray(130, 40) = 120</syntaxhighlight>

PrintN( Str(ArraySize(MultiArray2(), 2)) ; Will tell that second dimension size is '128'</syntaxhighlight>

 

=={{header|Python}}==

Python lists are dynamically resizeable.

 

array.append(1)

A simple, single-dimensional array can also be initialized thus:

 

 

However this will not work as intended if one tries to generalize from the syntax:

 

 

This creates a list of "height" number of references to one list object ... which is a list of width instances of the number zero. Due to the differing semantics of immutables (strings, numbers) and mutables (dictionaries, lists), a change to any one of the "rows" will affect the values in all of them. Thus we need to ensure that we initialize each row with a newly generated list.

To initialize a list of lists one could use a pair of nested list comprehensions like so:

 

 

That is equivalent to:

 

for x in range(height):

myArray.append([0] * width)</syntaxhighlight>

To retrieve an element in an array, use any of the following methods:

 

# Retrieve an element directly from the array.

item = array[index]

 

Python produces an IndexError when accessing elements out of range:

try:

# This will cause an exception, which will then be caught.

 

=={{header|QB64}}==

'Task

'Show basic array syntax in your language.

Dynamic

 

 

arr <- append(arr,3)

 

=={{header|Racket}}==

 

;; import dynamic arrays

At its most basic, an array in Raku is quite similar to an array in Perl 5.

 

push @arr, 1;

 

=={{header|REBOL}}==

a: [] ; Empty.

b: ["foo"] ; Pre-initialized.

Inserting and appending.

 

append a ["up" "down"] ; -> ["up" "down"]

insert a [left right] ; -> [left right "up" "down"]

Getting specific values.

 

first a ; -> left

third a ; -> "up"

you can even assign to it without destroying the list.

 

a ; -> [left right "up" "down"]

next a ; -> [right "up" "down"]

 

=={{header|Red}}==

arr2: ["apple" "orange" 1 2 3] ;create an array with data

>> insert arr1 "blue"

The allowable item types are: integer! float! char! percent!

Vectors of string! are not allowed.

== make vector! [20 30 70]

>> vec1/2

=={{header|ReScript}}==

 

 

let _ = Js.Array2.push(arr, 4)

Retro has a vocabulary for creating and working with arrays.

 

needs array'

 

 

===simple arrays===

a.='not found' /*value for all a.xxx (so far).*/

do j=1 to 100 /*start at 1, define 100 elements*/

 

===simple arrays, mimic other languages===

a. = 'not found' /*value for all a.xxx (so far). */

do j=1 to 100 /*start at 1, define 100 elements*/

 

===simple arrays, assigned default===

a. = 00 /*value for all a.xxx (so far). */

do j=1 to 100 /*start at 1, define 100 elements*/

 

===arrays with non-unity index start===

array. = 'out of range' /*define ALL elements to this. */

 

 

===arrays, disjoint===

yr. = 'year not supported' /*value for all yr.xxx (so far).*/

 

 

===sparse arrays and special indices===

yyy = -55 /*REXX must use this mechanism···*/

a.yyy = 1e9 /*··· when assigning neg indices.*/

Dynamic

 

a = ['foo']

 

 

=={{header|RLaB}}==

// 1-D (row- or column-vectors)

// Static:

Robotic does not natively support arrays of any kind.

However, using [https://www.digitalmzx.net/wiki/index.php?title=Counter_interpolation Counter Interpolation], we can create a simple (faux) array.

set "index" to 0

. "Assign random values to array"

 

You can even create multi-dimensional arrays using the Counter Interpolation method.

set "xx" to 0

set "yy" to 0

{{works with|ILE RPG}}

 

//-Static array

//--def of 10 el array of integers, initialised to zeros

Dynamic

 

a = ['foo']

 

 

=={{header|Run BASIC}}==

print "Enter array 2 greater than 0"; : input a2

By default, arrays are immutable unless defined otherwise.

 

let mut m = [1, 2, 3]; // mutable array

let zeroes = [0; 200]; // creates an array of 200 zeroes</syntaxhighlight>

To get the length and iterate,

 

a.len();

for e in a.iter() {

Accessing a particular element uses subscript notation, starting from 0.

 

names[1]; // second element</syntaxhighlight>

 

Dynamic arrays in Rust are called vectors.

 

 

However, this defines an immutable vector. To add elements to a vector, we need to define v to be mutable.

 

v.push(4);

v.len(); // 4</syntaxhighlight>

 

=={{header|Sather}}==

a :ARRAY{INT};

-- create an array of five "void" elements

=={{header|Scala}}==

Arrays are not used often in Scala, since they are mutable and act differently to other collections with respect to type erasure, but are necessary for interoperability with Java. Alternatives such as List, Seq, and Vector are more commonly used.

val a = new Array[Int](10)

 

val c = b(2)</syntaxhighlight>

Dynamic arrays can be made using <code>ArrayBuffer</code>s:

a += 5 // Append value 5 to the end of the list

a(0) = 6 // Assign value 6 to element 0</syntaxhighlight>

Lists are more often used in Scheme than vectors.

 

(array2 (make-vector 5)) ; default is unspecified

(array3 (make-vector 5 0))) ; default 0

Every type, which can be mapped to integer, can be used as index type.

 

 

const type: charArray is array [char] string; # Define an array type for arrays with char index.

Creating simple vectors:

 

A polymorphic vector:

 

Using a vector:

"creates an vector that holds up to 20 elements"

v: vector copySize: 20.

 

Enumeration:

v copy mapBy: [:each | each squared].

v copy filterBy: [:each | each > 10].</syntaxhighlight>

 

Using a squence:

"creates a new sequence"

s: sequence copyRemoveAll.

 

=={{header|SenseTalk}}==

set a to (1, 2, 3)

 

 

=={{header|Sidef}}==

var arr = [];

 

 

=={{header|Simula}}==

PROCEDURE STATIC;

</pre>

One can write an ArrayList class like Java has in package java.util.

 

CLASS ITEM;;

 

=={{header|Slate}}==

{1. 2. 3}

slate[2]> x

Literal Arrays (Array constants):

a polymorphic array containing integers, a string, a float, booleans, a nil, another array with integers and a character constant.

 

Programatic use:

"creates an array that holds up to 20 elements"

array := Array new: 20 .

array at: 2 put: 'orange'.</syntaxhighlight>

 

"suppose array is bound to an array of 20 values"

array at: 5 put: 'substitute fifth element'.

do: [ :sig | 'Out of range!' displayNl ].</syntaxhighlight>

 

#($a $b $c) at: 2</syntaxhighlight>

 

Enumeration:

array collect:[:each | each squared|

array select:[:each | each > 10]</syntaxhighlight>

{{works with|Squeak}}

Constructing an Array from evaluated expressions:

this construct evaluates each expression and creates a 4-element array containing a time, int, date and string object.

 

OrderedCollection:

oc add:1. oc add:2. oc add:3.

foo := oc removeFirst.

=={{header|SNOBOL4}}==

SNOBOL4 supports multi-dimensional arrays and array initialization.

fill i = LT(i, 3) i + 1 :F(display)

ar<i,1> = i

 

=={{header|SPL}}==

a[2] = 3

a[3] = "Result is "

done: ; program continues</pre>

We are now in a position to translate this algorithm into SSEM instructions and run it. As always, the SSEM version is a bit fiddlier than the pseudocode because the SSEM has no <tt>load</tt> or <tt>add</tt> instructions; but it follows the pseudocode as closely as the instruction set allows, so it should be comparatively readable. As a test, we shall sum an array of the first four positive integers—a very significant operation for the Pythagoreans of old—and halt with the accumulator holding the result.

11101000000000010000000000000000 1. Sub. 23

00101000000001100000000000000000 2. c to 20

 

=={{header|Standard ML}}==

(* create first array and assign elements *)

-val first = Array.tabulate (10,fn x=>x+10) ;

 

=== Matrix command ===

display det(a)

matrix svd u d v = a

 

=== Mata ===

a = 2,9,4\7,5,3\6,1,8

det(a)

 

=={{header|Suneido}}==

array.Add('three')

array.Add('five', at: 5)

 

=={{header|Swift}}==

var anyArray = [Any]()

anyArray.append("foo") // Adding to an Array

 

=={{header|Tailspin}}==

// arrays are created as literals, by simply listing elements, or by a generator expression, or a combination.

def a: [1, 2, 3..7:2, 11];

=={{header|Tcl}}==

Tcl's lists are really dynamic array values behind the scenes. (Note that Tcl uses the term “array” to refer to an associative collection of variables.)

 

lappend ary 1

puts [lindex $ary 0]</syntaxhighlight>

Note also that serialization is automatic on treating as a string:

 

=={{header|Tern}}==

Arrays and lists are synonymous in Tern.

 

for(i in list) {

<br>'''List'''<br>

One dimensional arrays are lists, they can be set as a whole with the syntax:

using only numerical values separated by commas and enclosed by curly braces.<br>

Lists can be accessed as a whole using L1-L6 or a custom list name

You can also retrieve a single value from a list using the name of the list and

the position of the value, which starts at 1 on the left.

Disp L1(3)

0→L1(4)</syntaxhighlight>

This would return 3 and set the fourth list element to 0.

<br>You can dynamically define or delete lists by:

DelVar L1

5→dim(∟MYLIST)

'''Matrix'''<br>

Two dimensional arrays are matrices. Similar, set them and retrieve numbers using the syntax:

Disp [A](1,3)

0→[A](4,2)</syntaxhighlight>

This would return 13 and set the element (4,2) to 0.

<br>You can dynamically define or delete matrices by:

DelVar [A]</syntaxhighlight>

 

Arrays in TorqueScript:

 

$array[0] = "hi";

$array[1] = "hello";

=> hello

 

$array["Greet",0] = "hi";

$array["Greet",1] = "hello";

Vectors can be created as empty containers, or they can be initialized with some values at the time of creation.

 

v1: Vector<Int>(),

v2: Vector<String>(),

Individual elements in a vector can be read, appended, and deleted.

 

(textout (get v 1)) // <= 2

(erase v 1)

All standard container operations can be applied to vectors:

 

(textout (reverse v)) // <= [4, 2, 5, 1, 3]

(textout (sort v)) // <= [1, 2, 3, 4, 5]

A complete program which turns comma-separated into tab-separated,

where the first and last field from each line are exchanged:

@line

@(bind f @(split-str line ","))

=={{header|uBasic/4tH}}==

uBasic/4tH has only one single, global array of 256 integers. Since it's fixed, it can't be declared.

 

=={{header|Unicon}}==

Unicon's arrays are provided by the list type, which is a hybrid list/array type.

Lists of integers or reals, if not polluted by other types nor changed in size, may use a C-compatible internal representation (long and double).

 

=={{header|UNIX Shell}}==

 

To create an array:

declare -a list2 # declare an empty list called "list2"

declare -a list3[0] # empty list called "list3"; the subscript is ignored

list5=([3]=apple [2]=cherry [1]=banana [0]=strawberry)</syntaxhighlight>

To obtain the number of items in an array:

echo "The number of items in alist is ${#alist[*]}"</syntaxhighlight>

To iterate up over the items in the array:

while [[ $x < ${#alist[*]} ]]; do

echo "Item $x = ${alist[$x]}"

done</syntaxhighlight>

To iterate down over theitems in an array:

while [[ $x > 0 ]]; do # while there are items left

: $((x--)) # decrement first, because indexing is zero-based

done</syntaxhighlight>

To append to an array, use the current number of items in the array as the next index:

To make appending easier, use a little shell function, let's call it "push", and design it to allow appending multiple values, while also preserving quoted values:

# push LIST VALUES ...

push() {

push alist many words to add</syntaxhighlight>

To delete a single array item, the first item:

To delete and return the last item in an array (e.g., "pop" function):

 

pop() {

No items in alist</syntaxhighlight>

To delete all the items in an array:

To delete the array itself (and all items in it, of course):

 

=={{header|உயிர்/Uyir}}==

இருபரிமாணணி வகை எண் அணி {3, 3};

இருபரிமாணணி2 வகை எண் அணி {3} அணி {3};

=={{header|Vala}}==

Non-dynamic arrays:

int[] array = new int[10];

 

{{libheader|Gee}}

Dynamic Arrays with Gee:

var array = new ArrayList<int> ();

 

=={{header|VBA}}==

The Option Base statement is used at the module level to declare the default lower bound for array subscripts.

'create an array,

Dim a(3) As Integer

 

=={{header|VBScript}}==

 

'create a static array

 

=={{header|VHDL}}==

entity Array_Test is

end entity Array_Test;

=={{header|Vim Script}}==

Lists can be used for dynamic arrays. Indexing starts at 0.

let array = [3, 4]

 

 

=={{header|Visual Basic .NET}}==

Dim numbers As Integer() = New Integer(9) {}

'Example of array of 4 string types:

 

=={{header|Vlang}}==

// Tectonics: v run arrays.v

module main

 

=={{header|Wee Basic}}==

let array$(1)="Hello!"

let array$(2)="Goodbye!"

 

=={{header|Wren}}==

arr.add(1)

arr.add(2)

 

=={{header|X86 Assembly}}==

section .text

global _start

=={{header|XBS}}==

Arrays in [[XBS]] are very similar to [[JavaScript]].

log(Array[0]);

Array.push("Test");

=={{header|XLISP}}==

Like some other languages, XLISP refers to one-dimensional arrays as vectors. Examples of vector and array syntax, from a REPL (interactive session):

 

A

 

=={{header|XPL0}}==

char A(10); \creates a static array of 10 bytes, pointed to by "A"

char B; \declares a variable for a pointer to a dynamic array

 

=={{header|Yabasic}}==

// Indexed at your preference (0 to 9 or 1 to 10)

print arraysize(a(), 1) // this function return the element's higher number of an array

 

An array is nothing more than a contiguous section of memory. Whether an array is mutable or not is solely determined by whether its memory location is in ROM or RAM.

byte 0,0,0,0,0

byte 0,0,0,0,0

 

This code will assign a value of decimal 20 to the 1st (zero-indexed) row and 2nd (zero-indexed) column. The resulting array will look like this:

byte 0,0,0,0,0

byte 0,0,20,0,0

 

 

 

ld hl,Array ;hl points to the 0th element of row 0.

In the example below, we wish to load the 13th (zero-indexed) element from the array MyTable.

 

;>LABEL means "the high byte of the address represented by LABEL

LD L,13 ;this was a lot faster than doing LD HL,&0400 and adding the desired index later.

 

That might have been a bit confusing, so let's visualize the concept. Here's a practical example of storing a sine wave pattern. Instead of storing 16-bit data together like you normally would:

word &8000,&8327,&864e,&8973,&8c98,&8fba,&92da,&95f7

word &9911,&9c27,&9f38,&a244,&a54c,&a84d,&ab48,&ae3c

 

You can instead store it like this:

byte <&8000,<&8327,<&864e,<&8973,<&8c98,<&8fba,<&92da,<&95f7

byte <&9911,<&9c27,<&9f38,<&a244,<&a54c,<&a84d,<&ab48,<&ae3c

 

So let's say we want to read the last entry in "the table".

LD L,&1F ;desired index

ld a,(hl)

=={{header|zkl}}==

Core zkl does not support arrays or vectors of one type. It does support heterogeneous lists, which are usually a super set at the cost of space.

array=(0).pump(10,List().write,5).copy(); // [writable] array of size 10 filled with 5

array[3]=4;

 

=={{header|zonnon}}==

var

a: array 10 of integer;

 

=={{header|ZX Spectrum Basic}}==

20 LET a(2)=128

30 PRINT a(2)</syntaxhighlight>