recip ( x -- y )
Factor handbook » The language » Numbers » Mathematical functions » Arithmetic functions

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Vocabulary
math

Inputs

x

a number

Outputs

y

a number

Word description
Computes a number's multiplicative inverse.

Errors
Throws an error if x is the integer 0.

Definition

IN: math

GENERIC: recip ( x -- y )

Methods

USING: kernel math math.ratios math.ratios.private ;

M: integer recip
    1 swap
    [ division-by-zero ]
    [ dup 0 < [ [ neg ] bi@ ] when fraction> ] if-zero ;


USING: math math.matrices math.matrices.extras.private ;

M: matrix recip (specialized-inverse) ; inline


USING: kernel math ;

M: number recip 1 swap / ; inline


USING: kernel math math.ratios.private ;

M: ratio recip
    >fraction swap dup 0 < [ [ neg ] bi@ ] when fraction> ;


USING: math math.matrices math.matrices.extras.private ;

M: square-matrix recip (square-inverse) ; inline


USING: math math.matrices ;

M: zero-matrix recip transpose ; inline


USING: math math.matrices ;

M: zero-square-matrix recip ; inline