f(lgamma/1)

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- Packages

Availability:Arithmetic function (see is/2)

lgamma(+Expr)

Return the natural logarithm of the absolute value of the Gamma function.^{133Some interfaces also
provide the sign of the Gamma function. We cannot do that in an
arithmetic function. Future versions may provide a predicate
lgamma/3 that returns both the value and the sign.}