sgn ( x -- n )
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Vocabulary
math

Inputs

x

a real

Outputs

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

USING: kernel ;

IN: math

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