The general form of the DO WHILE statement is as follows:
With a WHILE clause, the expression is evaluated at the beginning of each loop, with iterations continuing until the expression is false (that is, until the expression contains a zero or a missing value). Note that if the expression is false the first time it is evaluated, the loop is not executed.
For example, the following statements initialize count
to 1 and then increment count
four times:
count = 1; do while(count<5); count = count+1; end;