gamma ( x -- value )


Vocabulary
picomath

Inputs and outputs
xan object
valuean object


Definition


:: gamma ( x -- value )
x 0 <= [ "Invalid input" throw ] when x {
{ [ dup 0.001 < ] [ GAMMA * 1.0 + x * 1.0 swap / ] }
{ [ dup 12.0 < ] [ (gamma) ] }
{ [ dup 171.624 > ] [ drop 1/0. ] }
[ log-gamma e^ ]
} cond ;