GAMMA — Gamma function

GAMMA(X)

GAMMA(X) computes Gamma (Gamma) of X. For positive, integer values of X the Gamma function simplifies to the factorial function Gamma(x)=(x-1)!.

Parameters:

X – Shall be of type REAL and neither zero nor a negative integer.

Returns:

The return value is of type REAL of the same kind as X.

Standard:

Fortran 2008 and later

Class:

Elemental function

Syntax:

X = GAMMA(X)

Example:

program test_gamma
  real :: x = 1.0
  x = gamma(x) ! returns 1.0
end program test_gamma

Specific names:

Name	Argument	Return type	Standard
DGAMMA(X)	REAL(8) X	REAL(8)	GNU extension

See also:

Logarithm of the Gamma function: LOG_GAMMA