The earliest high-level programming languages, including FORTRAN (1957), Lisp (1958), COBOL (1960), and ALGOL 60 (1960), had support for multi-dimensional arrays, and so has C (1972). Īssembly languages generally have no special support for arrays, other than what the machine itself provides. Some mainframes designed in the 1960s, such as the Burroughs B5000 and its successors, used memory segmentation to perform index-bounds checking in hardware. p. 159 Array indexing was originally done by self-modifying code, and later using index registers and indirect addressing. John von Neumann wrote the first array-sorting program ( merge sort) in 1945, during the building of the first stored-program computer. The first digital computers used machine-language programming to set up and access array structures for data tables, vector and matrix computations, and for many other purposes. The term is also used, especially in the description of algorithms, to mean associative array or 'abstract array', a theoretical computer science model (an abstract data type or ADT) intended to capture the essential properties of arrays. Array types are often implemented by array structures however, in some languages they may be implemented by hash tables, linked lists, search trees, or other data structures. The term 'array' may also refer to an array data type, a kind of data type provided by most high-level programming languages that consists of a collection of values or variables that can be selected by one or more indices computed at run-time. The set of valid index tuples and the addresses of the elements (and hence the element addressing formula) are usually, but not always, fixed while the array is in use. For that reason, the elements of an array data structure are required to have the same size and should use the same data representation. Among other things, this feature allows a single iterative statement to process arbitrarily many elements of an array.

Processors, especially vector processors, are often optimized for array operations.Īrrays are useful mostly because the element indices can be computed at run time. In most modern computers and many external storage devices, the memory is a one-dimensional array of words, whose indices are their addresses. They effectively exploit the addressing logic of computers. They are also used to implement many other data structures, such as lists and strings. Tables are often implemented in the form of arrays, especially lookup tables the word 'table' is sometimes used as a synonym of array.Īrrays are among the oldest and most important data structures, and are used by almost every program. In some cases the term 'vector' is used in computing to refer to an array, although tuples rather than vectors are the more mathematically correct equivalent. The memory address of the first element of an array is called first address, foundation address, or base address.īecause the mathematical concept of a matrix can be represented as a two-dimensional grid, two-dimensional arrays are also sometimes called 'matrices'. , 0x7F4) so that the element with index i has the address 2000 + ( i × 4). The simplest type of data structure is a linear array, also called one-dimensional array.įor example, an array of ten 32-bit (4-byte) integer variables, with indices 0 through 9, may be stored as ten words at memory addresses 2000, 2004, 2008. An array is stored such that the position of each element can be computed from its index tuple by a mathematical formula. In computer science, an array is a data structure consisting of a collection of elements ( values or variables), of same memory size, each identified by at least one array index or key. JSTOR ( September 2008) ( Learn how and when to remove this template message).Unsourced material may be challenged and removed.įind sources: 'Array' data structure – news Please help improve this article by adding citations to reliable sources. This article needs additional citations for verification.

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