Statements |
Valid: | in a DATA step |
Category: | Information |
Type: | Declarative |
Syntax |
ARRAY array-name { subscript } <$><length>
<array-elements> <(initial-value-list)>; |
specifies the name of the array.
Restriction: | Array-name must be a SAS name that is not the name of a SAS variable in the same DATA step. |
If you inadvertently use a function name as the name of the array, SAS treats parenthetical references that involve the name as array references, not function references, for the duration of the DATA step. A warning message is written to the SAS log.
describes the number and arrangement of elements in the array by using an asterisk, a number, or a range of numbers. Subscript has one of these forms:
specifies the number of elements in each dimension of the array. Dimension-size is a numeric representation of either the number of elements in a one-dimensional array or the number of elements in each dimension of a multidimensional array.
are the bounds of each dimension of an array, where lower is the lower bound of that dimension and upper is the upper bound.
specifies that SAS is to determine the subscript by counting the variables in the array. When you specify the asterisk, also include array-elements.
Restriction: | You cannot use the asterisk with _TEMPORARY_ arrays or when you define a multidimensional array. |
specifies that the elements in the array are character elements.
Tip: | The dollar sign is not necessary if the elements have been previously defined as character elements. |
specifies the length of elements in the array that have not been previously assigned a length.
specifies the names of the elements that make up the array. Array-elements must be either all numeric or all character, and they can be listed in any order. The elements can be
Range: | The names must be either variables that you define in the ARRAY statement or variables that SAS creates by concatenating the array name and a number. For example, when the subscript is a number (not the asterisk), you do not need to name each variable in the array. Instead, SAS creates variable names by concatenating the array name and the numbers 1, 2, 3, ...n. |
Tip: | These SAS variable lists enable you to reference variables that have been previously defined in the same DATA step: |
Restriction: | If you use _ALL_, all the previously defined variables must be of the same type. |
Featured in: | Defining Arrays |
creates a list of temporary data elements.
gives initial values for the corresponding elements in the array. The values for elements can be numbers or character strings. You must enclose all character strings in quotation marks. To specify one or more initial values directly, use the following format:
To specify an iteration factor and nested sublists for the initial values, use the following format:
<constant-iter-value*> <(>constant value | constant-sublist<)>
Restriction: | If you specify both an initial-value-list and array-elements, then array-elements must be listed before initial-value-list in the ARRAY statement. |
Tip: | You can assign initial values to both variables and temporary data elements. |
Tip: | Elements and values are matched by position. If there are more array elements than initial values, the remaining array elements receive missing values and SAS issues a warning. |
Featured in: | Assigning Initial Numeric Values, and Defining Initial Character Values |
Tip: | You can separate the values in the initial value list with either a comma or a blank space. |
Tip: | You can also use a shorthand notation for specifying a range of sequential integers. The increment is always +1. |
Tip: |
If you have not previously
specified the attributes of the array elements (such as length or type), the
attributes of any initial values that you specify are automatically assigned
to the corresponding array element.
Note: Initial values are retained until a new value is assigned to the array element. |
Tip: | When any (or all) elements are assigned initial values, all elements behave as if they were named on a RETAIN statement. |
Examples: | The following examples show how to use the iteration factor and nested sublists. All of these ARRAY statements contain the same initial value list: |
Details |
The ARRAY statement defines a set of elements that you plan to process as a group. You refer to elements of the array by the array name and subscript. Because you usually want to process more than one element in an array, arrays are often referenced within DO groups.
Comparisons |
Arrays in the SAS language are different from arrays in many other languages. A SAS array is simply a convenient way of temporarily identifying a group of variables. It is not a data structure, and array-name is not a variable.
An ARRAY statement defines an array. An array reference uses an array element in a program statement.
Examples |
array rain {5} janr febr marr aprr mayr;
array days{7} d1-d7;
array month{*} jan feb jul oct nov;
array x{*} _NUMERIC_;
array qbx{10};
array meal{3};
array test{4} t1 t2 t3 t4 (90 80 70 70);
array test{4} t1-t4 (90 80 2*70);
array test{4} _TEMPORARY_ (90 80 70 70);
array new{2:5} green jacobs denato fetzer;
array x{5,3} score1-score15;
array test{3:4,3:7} test1-test10;
array temp{0:999} _TEMPORARY_;
array x{10} (2*1:5);
The following example shows that you can create a range of variable names that have leading zeros. Each variable name has a length of three characters, and the names sort correctly (A01, A02, ... A10). Without leading zeros, the variable names would sort in the following order: A1, A10, A2, ... A9.
options pageno=1 nodate ps=64 ls=80; data test (drop=i); array a(10) A01-A10; do i=1 to 10; a(i)=i; end; run; proc print noobs data=test; run;
Array Names That Have Leading Zeros
The SAS System 1 A01 A02 A03 A04 A05 A06 A07 A08 A09 A10 1 2 3 4 5 6 7 8 9 10
See Also |
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Array Processing in SAS Language Reference: Concepts |
Copyright © 2011 by SAS Institute Inc., Cary, NC, USA. All rights reserved.