Creating an Array

Creating an Array
You are encouraged to solve this task according to the task description, using any language you may know.

This task is about numeric arrays. For hashes or associative arrays, please see Creating an Associative Array.

In this task, the goal is to create an array. Mention if the array base begins at a number other than zero.

ActionScript

//  ActionScript arrays are zero-based
// 
//  creates an empty array
var arr1:Array = new Array();
//  creates an array with 3 numerical values
var arr2:Array = new Array(1,2,3);
// 
// or just use the shorthand
var u:Array = [];
var v:Array = [1,2,3];

Ada

Compiler: GCC 4.1.2

Ada array indices may begin at any value, not just 0 or 1

type Arr is array (Integer range <>) of Integer;
Uninitialized : Arr (1 .. 10);
Initialized_1 : Arr (1 .. 20) := (others => 1);
Initialized_2 : Arr := (1 .. 30 => 2);
Const         : constant Arr := (1 .. 10 => 1, 11 .. 20 => 2, 21 | 22 => 3);
Centered      : Arr (-50..50) := (0 => 1, Others => 0);

Ada arrays may be indexed by enumerated types, which are discrete non-numeric types

type Days is (Mon, Tue, Wed, Thu, Fri, Sat, Sun);
type Activities is (Work, Fish);
type Daily_Activities is array(Days) of Activities;
This_Week : Daily_Activities := (Mon..Fri => Work, Others => Fish);

AppleScript

AppleScript arrays are called lists:

set empty to {}
set ints to {1, 2, 3}

Lists can contain any objects including other lists:

set any to {1, "foo", 2.57, missing value, ints}

BASIC

Interpeter: QuickBasic 4.5, PB 7.1

REM Force index to start at 1..n
OPTION BASE 1

REM Force index to start at 0..n
OPTION BASE 0

REM Specify that the array is dynamic and not static
'$DYNAMIC
DIM SHARED myArray(-10 TO 10, 10 TO 30) AS STRING
REDIM SHARED myArray(20, 20) AS STRING
myArray(1,1) = "Item1"
myArray(1,2) = "Item2"

C

Compiler: gcc, MSVC, BCC, Watcom

Dynamic

#include <stdlib.h> /* for malloc */
#include <string.h> /* for memset */
int n = 10 * sizeof(int);
int *myArray = (int*)malloc(n);
if(myArray != NULL)
{
  memset(myArray, 0, n);
  myArray[0] = 1;
  myArray[1] = 2;
  free(myArray);
  myArray = NULL;
}

Static

 int myArray2[10] = { 1, 2, 0}; /* 3..9 := 0 */

C++

Compiler: g++, Visual C++, BCC, Watcom

Using dynamically-allocated memory:

 const int n = 10;
 int* myArray = new int[n];
 if(myArray != NULL)
 {
   myArray[0] = 1;
   myArray[1] = 2;
   delete[] myArray;
   myArray = NULL;
 }

Using fixed memory:

 int myArray2[10] = { 1, 2, 0}; /* 3..9 := 0 */

Libraries: STL

 // STL
 std::vector<int> myArray3(10);
 myArray3.push_back(1);
 myArray3.push_back(2);

Libraries: Qt

 // Qt
 QVector<int> myArray4(10);
 myArray4.push_back(1);
 myArray4.push_back(2);

Libraries: Microsoft Foundation Classes

 // MFC
 CArray<int,int> myArray5(10);
 myArray5.Add(1);
 myArray5.Add(2);

C#

Example of array of 10 int types:

 int[] numbers = new int[10];

Example of array of 3 string types:

 string[] words = { "these", "are", "arrays" };

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

 int[] more_numbers = new int[3]{ 21, 14 ,63 };

For Multi-Deminsional arrays you declare them the same except for a comma in the type declaration.

The following creates a 3x2 int matrix

 int[,] number_matrix = new int[3,2];

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.

 string[,] string_matrix = { {"I","swam"}, {"in","the"}, {"freezing","water"} };

or

 string[,] funny_matrix = new string[2,2]{ {"clowns", "are"} , {"not", "funny"} };

Clean

Array denotations are overloaded in Clean, therefore we explicitly specify the types. There are lazy, strict, and unboxed array.

Lazy array

Create a lazy array of strings using an array denotation.

array :: {String}
array = {"Hello", "World"}

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

array :: {Real}
array = createArray 10 3.1415

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

array :: {Int}
array = {x \\ x <- [1 .. 10]}

Strict array

Create a strict array of integers.

array :: {!Int}
array = {x \\ x <- [1 .. 10]}

Unboxed array

Create an unboxed array of characters, also known as String.

array :: {#Char}
array = {x \\ x <- ['a' .. 'z']}

ColdFusion

Creates a one-dimensional Array

<cfset arr1 = ArrayNew(1)>

Creates a two-dimensional Array in CFScript

<cfscript>
  arr2 = ArrayNew(2);
</cfscript>

ColdFusion Arrays are NOT zero-based, they begin at index 1

Common Lisp

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

(make-array 10)

Creates a two-dimensional array with dimensions 10x20.

(make-array '(10 20))

make-array may be called with a number of optional arguments.

(make-array 4 :element-type 'integer :initial-contents '(1 2 3 4) :adjustable t)

D

Compiler: DMD,GDC

// dynamic array
int[] numbers = new int[5];

// static array
int[5] = [0,1,2,3,4];

E

[]                 # immutable, empty
[1,9,17]           # immutable, 3 elements
[].diverge()       # mutable, empty
[].diverge(int)    # mutable, integers only

Forth

Forth has a variety of ways to allocate arrays of data, though it has no built-in array handling words, favoring pointer manipulation.

Static array of 200 cells, uninitialized:

create MyArray 200 cells allot
here MyArray - cell / constant MyArraySize

Static array containing the numbers 1 to 5

create MyArray   1 , 2 , 3 , 4 , 5 ,
here MyArray - cell / constant MyArraySize

Dynamic array allocation:

0 value MyArray
200 cells allocate throw to MyArray

Dynamic array free:

MyArray free throw
0 to MyArray

Fortran

Default case:

      integer a(10)

this will have ten elements. Counting starts at 1. If a zero-based array is needed, declare like this:

      integer a(0:9)

this mechanism can be extended to any numerical indices, and allowed number of dimensions (and of course to other data types than integers). For example

      real*8 (25:29,12)

will be an two-dimensional, 5x12-array of 8-byte floats, where the first dimension can be addressed numerically as 25, 26, 27, 28 or 29 (and the second dimension as 1 .. 12).

IDL

IDL doesn't really distinguish between scalars and arrays - the same operations that can create the one can usually create the other as well.

 a = 3
 help,a
 A               INT       =        3
 print,a^2
      9

 a = [3,5,8,7]
 help,a
 A               INT       = Array[4]
 print,a^2
      9      25      64      49

Java

For example for an array of 10 int values:

 int[] intArray = new int[10];

Creating an array of Strings:

 String[] s = {"hello" , "World" };

JavaScript

 var myArray = new Array();
 var myArray2 = new Array("Item1","Item2");
 var myArray3 = ["Item1", "Item2"];

LSE64

10 myArray :array

MAXScript

Interpreter: 3D Studio Max 8

 myArray = #()
 myArray2 = #("Item1", "Item2")

mIRC Scripting Language

Interpeter: mIRC Script Editor Libraries: mArray Snippet

alias creatmearray { .echo -a $array_create(MyArray, 5, 10) }

OCaml

Using an array literal:

 let array = [| 1; 2; 3; 4; 5 |];;

To create an array of five elements with the value 0:

 let num_items = 5 and initial_value = 0;;
 let array = Array.make num_items initial_value

To create an array with contents defined by passing each index to a callback (in this example, the array is set to the squares of the numbers 0 through 4):

 let callback index = index * index;;
 let array = Array.init 5 callback

Perl

Interpreter: Perl 5

my @empty;
my @empty_too = ();

my @populated   = ('This', 'That', 'And', 'The', 'Other');
print $populated[2];
# And

my $aref = ['This', 'That', 'And', 'The', 'Other'];
print aref->[2];
# And

# having to quote like that really sucks, and that's why we got syntactic sugar
my @wakey_wakey = qw(coffee sugar cream);

push @wakey_wakey, 'spoon';
# add spoon to right-hand side
my $cutlery = pop @wakey_wakey;
# remove spoon

unshift @wakey_wakey, 'cup';
# add cup to left-hand side
my $container = shift @wakey_wakey;
# remove cup

my @multi_dimensional = (
    [0, 1, 2, 3],
    [qw(a b c d e f g)],
    [qw(! $ %

Pop11

Pop11 distinguishes between vectors and arrays. Vectors are one dimensional and the lowest index is 1. There is special shorthand syntax to create vectors:

;;; General creation of vectors, create initialized vector.
lvars v1 = consvector(1, 'a', "b", 3);
;;; Shorthand notation
lvars v2 = {1 'a' b};
;;; Create vector filled with word undef (to signal that elements
;;; are uninitialized)
lvars v3 = initv(3)

Pop11 arrays may have arbitrary lower and upper bounds:

;;; Create array with first index ranging from 2 to 5 and second
;;; index from -1 to 1, initialized with 0
vars a1 = newarray([2 5 -1 1], 0);

Python

List are mutable arrays. You can put anything into a list, including other lists.

empty = []
numbers = [1, 2, 3, 4, 5]
zeros = [0] * 10
anything = [1, 'foo', 2.57, None, zeros]
digits = range(10)  # 0, 1 ... 9
evens  = range(0,10,2)  # 0, 2, 4 ... 8
evens = [x for x in range(10) if not x % 2]  # same using list comprehension
words = 'perl style'.split()

Tuples are immutable arrays. Note hat tuples are defined by the "," - the parenthesis are optional:

empty = ()
numbers = (1, 2, 3, 4, 5)
zeros = (0,) * 10
anything = (1, 'foo', 2.57, None, zeros)

Both lists and tuples can be created from other iterateables:

>>> list('abc')
['a', 'b', 'c']
>>> tuple('abc')
('a', 'b', 'c')
>>> list({'a': 1, 'b': 2, 'c': 3})
['a', 'c', 'b']
>>> open('file', 'w').write('1\n2\n3\n')
>>> list(open('file'))
['1\n', '2\n', '3\n']

Raven

[ 1 2 3.14 'a' 'b' 'c' ] as a_list
a_list print

list (6 items)
 0 => 1
 1 => 2
 2 => 3.14
 3 => "a"
 4 => "b"
 5 => "c"

Ruby

I've used the same examples as the Python-example above. .

 empty = []
 #or:
 empty = Array.new
 numbers = [1, 2, 3, 4, 5]
 zeros = [0] * 10
 anything = [1, 'foo', 2.57, zeros]

Toka

Toka allows creation of an array using is-array. Access to the elements is done using get-element, put-element, get-char-element, and put-char-element functions. You can not initialize the values automatically using the core array functions.

 100 cells is-array foo
 100 chars is-array bar