sgn ( x -- n )
Factor handbook > The language > Numbers > Mathematical functions > Arithmetic functions

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Vocabulary
math

Inputs and outputs
xa real
n-1, 0 or 1


Word description
Outputs one of the following:
-1 if x is negative
0 if x is equal to 0
1 if x is positive


Definition


: sgn ( x -- n ) dup 0 < [ drop -1 ] [ 0 > 1 0 ? ] if ; inline