Reference/do

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do (do control word)

Syntax

The do statement has the form:

do[count;exp1;...;expn]

where count must evaluate to an integer. The remaining expressions are run in order, count times.

do does not return a result.

Example

Continued fraction for pi, for 7 steps:

q)r:()
q)t:2*asin 1
q)do[7;r,:q:floor t;t:reciprocal t-q]
q)r
3 7 15 1 292 1 1

do can be used for accurate timing of expressions, e.g. time log of first 100,000 numbers, over 100 trials:

q)\t do[100;log til 100000]
396

See also


For a complete list of functions, see the kdb+ Function Reference.

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