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DO WHILE |
Valid: | in a DATA step |
Category: | Control |
Type: | Executable |
Syntax | |
Arguments | |
Details | |
Comparisons | |
Examples | |
See Also |
Syntax |
DO WHILE (expression);
...more SAS statements... |
END; |
Details |
The expression is evaluated at the top of the loop before the statements in the DO loop are executed. If the expression is true, the DO loop iterates. If the expression is false the first time it is evaluated, the DO loop does not iterate even once.
Comparisons |
There are three other forms of the DO statement:
Note: If the expression is false,
the statements in a DO WHILE loop do not execute. However, because the DO
UNTIL expression is evaluated at the bottom of the loop, the statements in
the DO UNTIL loop always execute at least once.
Examples |
These statements repeat the loop while N is less than 5. The expression N<5 is evaluated at the top of the loop. There are five iterations in all (0, 1, 2, 3, 4).
n=0; do while(n<5); put n=; n+1; end;
See Also |
Statements:
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Copyright 1999 by SAS Institute Inc., Cary, NC, USA. All rights reserved.