log ( 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
Natural logarithm function. Outputs negative infinity if x is 0.

Definition

IN: math.functions

GENERIC: log ( x -- y )

Methods

USING: math math.functions math.functions.private ;

M: bignum log [ log ] log-2 (bignum-log) ;


USING: kernel math math.functions math.libm ;

M: complex log >polar [ flog ] dip rect> ; inline


USING: kernel math math.functions math.libm ;

M: float log dup 0.0 >= [ flog ] [ 0.0 rect> log ] if ; inline


USING: math math.functions ;

M: real log >float log ; inline