This comparison of programming languages (array) compares the features of array data structures or matrix processing for various computer programming languages.

Syntax

Array dimensions

The following list contains syntax examples of how to determine the dimensions (index of the first element, the last element or the size in elements).

Note particularly that some languages index from zero while others index from one while others carry no such restriction or even allow indexing by any enumerated type, not just integers.

Languages Size First Last
Ada name'Lengthname'Firstname'Last
ALGOL 68 UPB name - LWB name+1
2 UPB name - 2 LWB name+1
etc.		LWB name
2 LWB name
etc.		UPB name

2 UPB name
etc.

APL ⍴ name
(⍴ name)[index]		⎕IO(⍴ name)-~⎕IO
(⍴ name)[index]-~⎕IO
AWK length1asorti
C#, Visual Basic .NET, Windows PowerShell, F# name.Lengthname.GetLowerBound(dimension)name.GetUpperBound(dimension)
CFML arrayLen(name)
name.len()		1name.len()
Ch max(shape(name))0max(shape(name))-1
Common Lisp (length name)0(1- (length name))
D name.length0name.length-1
$-1
Fortran size(name)lbound(name)ubound(name)
Go len(name)0len(name) - 1
Haskell rangeSize (bounds name)fst (bounds name)snd (bounds name)
ISLISP (length name)0(1- (length name))
Icon *name1*name
Cobra, D, Haxe, Java, JavaScript, Scala name.length0name.length - 1
J #name0<:@#name
Julia length(name)
size(name)		begin
first.(axes(name))		end
last.(axes(name))
Lingo count(name)1getLast(name)
LiveCode length(name)1
first		-1
last
Lua #name1 by convention; any integer[1]#name
Mathematica Length[name]1
First[name]		-1
Last[name]
MATLAB, GNU Octave length(name)1end
Nim name.lenname.low[2]name.high
Oberon LEN(name)0LEN(name) - 1
Object Pascal Length(name)0
low(name)		Length(name)-1
high(name)
Objective-C (NSArray * only) [name count]0[name count] - 1
OCaml Array.length name0Array.length name - 1
Perl scalar(@name)$[$#name
PHP count(name)0count(name) - 1
PL/I dim(name[,dim])lbound(name[,dim])hbound(name[,dim])
Python len(name)0-1
len(name) - 1
R length(name)1length(name)
Raku @name.elems0@name.end
Red length? namename/1
first name		last name
Ruby name.size0
name.first		-1
name.size - 1
name.last
Rust name.len()0name.len() - 1
S-Lang length(name)0-1
length(name)-1
Scheme (vector-length vector)0(- (vector-length vector) 1)
Smalltalk name size1
name first		name size
name last
Swift name.count 0 name.count - 1
Unicon *name1*name
Visual Basic UBound(name)-LBound(name)+1LBound(name)UBound(name)
Wolfram Language Length[name]1
First[name]		-1
Last[name]
Xojo UBound(name)0UBound(name)
XPath/XQuery count($name)1count($name)
last()
array:size(name)[3]

Indexing

The following list contains syntax examples of how to access a single element of an array.

Format Languages
name[index] or name[index1, index2] etc. ALGOL 58, ALGOL 60, ALGOL 68, AWK, Julia, Modula, Pascal, Object Pascal, C#, S-Lang[4] Icon, Unicon
name[index] or name[index1; index2] etc.
or index⌷name or index1 index2⌷name etc.		 APL
name[index] ActionScript, C, CFML, Ch, Cobra, C++, D, Go, Haxe, Java, JavaScript, Lingo, Lua, Nim, Objective-C (NSArray *), Perl,[4] PHP, Python,[4] R, Ruby,[4] Rust, Swift
$name[index] Perl,[4] Windows PowerShell,[4] XPath/XQuery[3]
@name[index] Raku
name(index) or name(index1, index2) etc. Ada, ALGOL W, BASIC, COBOL, Fortran, RPG, GNU Octave, MATLAB, PL/I, Scala, Visual Basic, Visual Basic .NET, Xojo
$name(index) XPath/XQuery[3]
name.(index) OCaml
name.[index] F#, OCaml
name/index Red
name ! index Haskell
$name ? index XPath/XQuery[3]
(vector-ref name index) Scheme
(aref name index) Common Lisp
(elt name index) ISLISP
name[[index]] Mathematica,[4] Wolfram Language
name at:index Smalltalk
[name objectAtIndex:index] Objective-C (NSArray * only)
index{name J
name.item(index) or name @ index[5] Eiffel

Slicing

The following list contains syntax examples of how a range of element of an array can be accessed.

In the following table:

  • first – the index of the first element in the slice
  • last – the index of the last element in the slice
  • end – one more than the index of last element in the slice
  • len – the length of the slice (= end - first)
  • step – the number of array elements in each (default 1)
Format Languages
name[first:last] ALGOL 68,[6] Julia, Icon, Unicon
name[first+(⍳len)-⎕IO] APL
name[first:end:step] Python[7][8]
name[first:end] Go
name[first..last] Pascal, Object Pascal, Delphi, Nim
$name[first..last] Windows PowerShell
@name[first..last] Perl[9]
name[first..last]
name[first...end]
name[first, len]		 Ruby[8]
copy/part skip name first len Red
name(first..last) Ada[6]
name(first:last) Fortran,[6][7] GNU Octave, MATLAB[6][9]
name[[first;;last;;step]] Mathematica,[6][7][8] Wolfram Language
name[[first:last]] S-Lang[6][7][9]
name.[first..step..last] F#
name.slice(first, end) Haxe, JavaScript, Scala
name.slice(first, len) CFML
array_slice(name, first, len) PHP[8]
(subseq name first end) Common Lisp
(subseq name first end) ISLISP
Array.sub name first len OCaml
[name subarrayWithRange:NSMakeRange(first, len)] Objective-C (NSArray * only)
(first([+i.@(-~)end){name J
name[first..<end]
name[first...last]		 Swift
name copyFrom: first to:last
name copyFrom: first count:len 		Smalltalk
name[first..end] D, C#[10][11]
name[first..end]
name[first..=last] 		Rust
name[first:end] Cobra
table.move(name, first, last, 1, {}) Lua[12]

Array system cross-reference list

Language Default
base index		 Specifiable
index type[13]		 Specifiable
base index		 Bound check Multidimensional Dynamically-sized Vectorized operations
Ada index type[14] yes yes checked yes init[15] some, others definable[16]
ALGOL 68 1 no[17] yes varies yes yes user definable
APL 1  ? 0 or 1[18] checked yes yes yes
AWK 1 yes, implicitly no unchecked yes, as delimited string yes, rehashed no
BASIC 0  ? no checked no init[15]  ?
C 0 no no[19] unchecked partially init,[15][20] heap[21] no
Ch 0 no no checked yes, also array of array[22] init,[15][20] heap[21] yes
C++[16] 0 no no[19] unchecked yes, also array of array[22] heap[21] no
C# 0 no partial[23] checked yes heap[21][24] yes (LINQ select)
CFML 1 no no checked yes, also array of array[22] yes no
COBOL 1 no[25] no checked array of array[22][26] no[27] some intrinsics
Cobra 0 no no checked array of array[22] heap  ?
Common Lisp 0  ? no checked[28] yes yes yes (map or map-into)
D 0 yes[29] no varies[30] yes yes  ?
F# 0 no partial[23] checked yes heap[21][24] yes (map)
FreeBASIC 0 no yes checked yes init,[15] init[31]  ?
Fortran 1 yes yes varies[32] yes yes yes
FoxPro 1  ? no checked yes yes  ?
Go 0 no no checked array of array[22] no[33] no
Hack 0 yes yes checked yes yes yes
Haskell 0 yes[34] yes checked yes, also array of array[22] init[15]  ?
IDL 0  ? no checked yes yes yes
ISLISP 0  ? no checked yes init[15] yes (map or map-into)
J 0  ? no checked yes yes yes
Java[16] 0 no no checked array of array[22] init[15]  ?
JavaScript 0 no no checked[35] array of array[22] yes yes
Julia 1 yes yes checked (can be skipped locally; or globally by user) yes, also array of array yes yes
Lingo 1  ?  ? unchecked yes yes yes
Lua 1  ? partial[36] checked array of array[22] yes  ?
Mathematica 1 no no checked yes yes yes
MATLAB 1  ? no checked yes[37] yes yes
Nim 0 yes[2] yes optional[38] array of array[22] yes yes[39]
Oberon 0  ? no checked yes no  ?
Oberon-2 0  ? no checked yes yes  ?
Objective-C[16] 0 no no checked array of array[22] yes no
OCaml 0 no no checked by default array of array[22] init[15]  ?
Pascal, Object Pascal index type[14] yes yes varies[40] yes varies[41] some
Perl 0 no yes ($[) checked[35] array of array[22] yes no[42]
Raku 0 no no checked[35] yes yes yes
PHP 0 yes[43] yes[43] checked[43] yes yes yes
PL/I 1 yes yes optional yes no yes[44]
Python 0 no no checked array of array[22] yes no[45]
RPG 1 no no  ? no no  ?
R 1  ? no unchecked yes, also array of array yes yes
Ring 1  ? partial[36] checked array of array[22] yes  ?
Ruby 0 no no checked[35] array of array[22] yes  ?
Rust 0 no no checked array of array[22] no  ?
Sass 1 no no checked array of array[22] init[30]  ?
S-Lang 0  ? no checked yes yes yes
Scala 0 no no checked array of array[22] init[15] yes (map)
Scheme 0  ? no checked array of array[22] init[15] yes (map)
Smalltalk[16] 1  ? no checked array of array[22] yes[46]  ?
Swift 0 no no checked array of array[22] yes  ?
Visual Basic 0, 1, or index type[47] no yes checked yes yes  ?
Visual Basic .NET 0 or index type[47] no partial[23] checked yes yes yes (LINQ select)
Wolfram Language 1 no no checked yes yes yes
Windows PowerShell 0 no no checked yes heap  ?
Xojo 0 no no checked yes yes no
XPath/XQuery 1 no no checked array of array[3][22] yes yes

Vectorized array operations

Some compiled languages such as Ada and Fortran, and some scripting languages such as IDL, MATLAB, and S-Lang, have native support for vectorized operations on arrays. For example, to perform an element by element sum of two arrays, a and b to produce a third c, it is only necessary to write

c = a + b

In addition to support for vectorized arithmetic and relational operations, these languages also vectorize common mathematical functions such as sine. For example, if x is an array, then

y = sin (x)

will result in an array y whose elements are sine of the corresponding elements of the array x.

Vectorized index operations are also supported. As an example,

even = x(2::2);
odd = x(::2);

is how one would use Fortran to create arrays from the even and odd entries of an array. Another common use of vectorized indices is a filtering operation. Consider a clipping operation of a sine wave where amplitudes larger than 0.5 are to be set to 0.5. Using S-Lang, this can be done by

y = sin(x);
y[where(abs(y)>0.5)] = 0.5;

Mathematical matrix operations

Language/
Library		 Create Determinant Transpose Element Column Row Eigenvalues
APL m←dims⍴x11 x12 ... -.×m ⍉m m[i;j] or i j⌷m m[;j] or j⌷[2]m or
j⌷⍤1⊢m or j⌷⍉m		 m[i;] or i⌷m ⌹⍠1⊢m
Fortran m = RESHAPE([x11, x12, ...], SHAPE(m)) TRANSPOSE(m) m(i,j) m(:,j) m(i,:)
Ch[48] m = {...} determinant(m) transpose(m) m[i-1][j-1] shape(m,0) shape(m,1) eigen(output, m, NULL)
Mathematica /
Wolfram Language		 {{x11, x12, ...}, ...} Det[m] Transpose[m] m[[i,j]] m[[;;,j]] m[[i]] Eigenvalues[m]
MATLAB /
GNU Octave		 m = [...] det(m) m.' m(i,j) m(:,j) m(i,:) eig(m)
NumPy m = mat(...) linalg.det(m) m.T m[i-1,j-1] m[:,j-1] m[i-1,:] linalg.eigvals(m)
R m <- matrix(...) or m <- array(...) det(m) t(m) m[i, j] m[, j] m[i, ] eigen(m)
S-Lang m = reshape([x11, x12, ...], [new-dims]) m = transpose(m) m[i,j] m[*,j] m[j,*]
SymPy m = Matrix(...) m.T m[i-1,j-1]

References

  1. ↑ "Programming in Lua : 11.1".
  2. 1 2 "Nim Tutorial (Part I)".
  3. 1 2 3 4 5 XPath/XQuery has two kinds of arrays. Sequences (1,2,3) which cannot nest and in the XPath/XQuery 3.1 version arrays array { 1,2,3 } or [1,2,3] which can.
  4. 1 2 3 4 5 6 7 The index may be a negative number, indicating the corresponding number of places before the end of the array.
  5. ↑ "Eiffeldoc : ARRAY".
  6. 1 2 3 4 5 6 Slices for multidimensional arrays are also supported and defined similarly.
  7. 1 2 3 4 Slices of the type first:last:step are also supported.
  8. 1 2 3 4 last or end may be a negative number, indicating to stop at the corresponding number of places before the end of the array.
  9. 1 2 3 More generally, for 1-d arrays Perl and S-Lang allow slices of the formarray[indices], where indices can be a range such mentioned in footnote 2 or an explicit list of indices, e.g., '[0,9,3,4]', or a mix of both, e.g., A[[[0:3]],7,9,[11:2:-3]]].
  10. ↑ C# 8.0 proposed feature (as of 29 August 2019)
  11. ↑ "Ranges - C# 8.0 language proposals". Microsoft Docs. Microsoft. Retrieved 29 August 2019.
  12. ↑ "Lua 5.3 Reference Manual". www.lua.org. Retrieved 2022-04-02.
  13. ↑ The index type can be a freely chosen integer type, enumerated type, or character type. For arrays with non-compact index types see: Associative array
  14. 1 2 The default base index is the lowest value of the index type used
  15. 1 2 3 4 5 6 7 8 9 10 11 Size can only be chosen on initialization after which it is fixed.
  16. 1 2 3 4 5 This list is strictly comparing language features. In every language (even assembler) it is possible to provide improved array handling via add on libraries. This language has improved array handling as part of its standard library
  17. ↑ ALGOL 68 arrays must be subscripted (and sliced) by type INT. However a hash function could be used to convert other types to INT. e.g. name[hash("string")]
  18. ↑ The indexing base can be 0 or 1 as per the System Variable ⎕IO. This value may apply to the whole "workspace", or be localized to a user-defined function or a single primitive function by use of the Variant operator (⍠).
  19. 1 2 Because C does not bound-check indices, a pointer to the interior of any array can be defined that will symbolically act as a pseudo-array that accommodates negative indices or any integer index origin.
  20. 1 2 C99 allows for variable size arrays; however there is almost no compiler available to support this new feature
  21. 1 2 3 4 5 Size can only be chosen on initialization when memory is allocated on the heap, as distinguished from when it is allocated on the stack. This note need not be made for a language that always allocates arrays on the heap.
  22. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Allows arrays of arrays which can be used to emulate most—but not all—aspects multi-dimensional arrays
  23. 1 2 3 The base can be changed when initializing with System.Array.CreateInstance (which returns System.Array), but not when using the language syntax. Arrays with non-zero base indices are not the same type as those with zero base indices and cannot be manipulated using language syntax (the GetValue and SetValue methods must be used instead) or downcast to a specific type (T[] in C#, or T() in VB.NET), preventing breakage of code assuming base indices of zero.
  24. 1 2 Allows creating fixed-size arrays in "unsafe" code, allowing enhanced interoperability with other language
  25. ↑ COBOL arrays may be indexed with "INDEX" types, distinct from integer types
  26. ↑ While COBOL only has arrays-of-arrays, array elements can be accessed with a multi-dimensional-array-like syntax, where the language automatically matches the indexes to the arrays enclosing the item being referenced
  27. ↑ COBOL provides a way to specify that the usable size of an array is variable, but this can never be greater than the declared maximum size, which is also the allocated size
  28. ↑ Most Common Lisp implementations allow checking to be selectively disabled
  29. ↑ Associative Arrays - D Programming Language
  30. 1 2 Behaviour can be tuned via compiler switches. As in DMD 1.0 bounds are checked in debug mode and unchecked in release mode for efficiency
  31. ↑ FreeBASIC supports both variable array lengths and fixed length arrays. Arrays declared with no index range are created as variable-length arrays, while arrays with a declared range are created as fixed-length arrays
  32. ↑ Almost all Fortran implementations offer bounds checking options via compiler switches. However by default, bounds checking is usually turned off for efficiency
  33. ↑ While Golang's Array type is not dynamically sized, the data type Slice is dynamically-sized and is much more common in use than arrays.
  34. ↑ Haskell arrays (Data.Array) allow using any type which is an instance of Ix as index type. So a custom type can be defined and used as an index type as long as it instances Ix. Also, tuples of Ix types are also Ix types; this is commonly used to implement multi-dimensional arrays
  35. 1 2 3 4 In these languages, one can access or write to an array index greater than or equal to the length of the array, and the array will implicitly grow to that size. This may appear at first as if the bounds are not checked; however, the bounds are checked in order to decide to grow the array, and you do not have unsafe memory access like you do in C.
  36. 1 2 By specifying a base index, arrays at an arbitrary base can be created. However, by default, Lua's length operator does not consider the base index of the array when calculating the length. This behavior can be changed via metamethods.
  37. ↑ At least 2 dimensions (scalar numbers are 1×1 arrays, vectors are 1×n or n×1 arrays).
  38. ↑ "Nim Compiler User Guide".
  39. ↑ "Vectorization - R-style logical vector operation in Nim".
  40. ↑ Many implementations (Turbo Pascal, Object Pascal (Delphi), FreePascal) allow the behaviour to be changed by compiler switches and in-line directives
  41. ↑ Varies by implementation. Newer implementations (FreePascal, Object Pascal (Delphi)) allow heap-based dynamic arrays.
  42. ↑ Standard Perl array data types do not support vectorized operations as defined here. However, the Perl Data Language extension adds array objects with this ability.
  43. 1 2 3 PHP's "arrays" are associative arrays. You can use integers and strings as the keys (indexes); floats can also be used as the key but are truncated to integers. There is not really any "base index" or "bounds"
  44. ↑ Size can be chosen when the array is declared, or when it is allocated, after which it is fixed.
  45. ↑ The standard Python array type, list, does not support vectorized operations as defined here. However, the numpy extension adds array objects with this ability
  46. ↑ The class Array is fixed-size, but OrderedCollection is dynamic
  47. 1 2 Microsoft QBASIC, QuickBASIC, Visual Basic, and VBA all had/have the ability to specify Option Base 1, which caused all arrays in the module to default starting at 1 instead of 0. Support for Option Base was phased out in Visual Basic .NET. In various Microsoft BASIC implementations, arrays can be DIMensioned using to in order to specify the minimum and maximum index values (e.g. DIM MyArray(2 to 50) AS STRING would have the first index at 2 instead of the default).
  48. ↑ Ch numerical features
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