Gamma Function and Related Functions
Routines
Factorial Function
Evaluates the factorial, n!
, FAC Evaluates the binomial coefficient.
, BINOM Gamma Function
Evaluates the real or complex gamma function, Γ(
x)
, GAMMA Evaluates the reciprocal of the real or complex gamma function, 1/ Γ(
x)
, GAMR Evaluates the real or complex function, ln
ǀγ(
x)
ǀ, ALNGAM Evaluates the log abs gamma function and its sign
, ALGAMS Incomplete Gamma Function
Evaluates the incomplete gamma function, γ(
a,
x)
, GAMI Evaluates the complementary incomplete gamma function, Γ(
a,x)
, GAMIC Evaluates Tricomi’s incomplete gamma function, γ*(
a,
x)
, GAMIT Psi Function
Evaluates the real or complex psi function, ψ(
x)
, PSI Evaluates the real psi1 function, ψ
1(
x)
, PSI1 Pochhammer’s Function
Evaluates Pochhammer’s generalized symbol, (
a)
x, POCH Evaluates Pochhammer’s symbol starting from the first order
, POCH1 Beta Function
Evaluates the real or complex beta function, β(
a,
b)
, BETA Evaluates the log of the real or complex beta function, ln β(
a,
b)
, ALBETA Evaluates the incomplete beta function,
Ix(
a,
b)
, BETAI 
