sigmoid ( x -- y ) (original) (raw)

sigmoid ( x -- y )
Factor handbook » The language » Numbers » Mathematical functions » Powers and logarithms

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Vocabulary
math.functions

Inputs

x a number

Outputs

y a number

Word description
Outputs the sigmoid, an S-shaped "logistic" function, from 0 to 1, of the number x.

Definition

USING: math ;

IN: math.functions

: sigmoid ( x -- y ) neg e^ 1 + recip ; inline