8.96 GAMMA
— Gamma function
- Description:
-
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)!.
- Standard:
- Fortran 2008 and later
- Class:
- Elemental function
- Syntax:
-
X = GAMMA(X)
- Arguments:
-
X |
Shall be of type REAL and neither zero nor a negative integer. |
- Return value:
- The return value is of type
REAL
of the same kind as 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 |
GAMMA(X) |
REAL(4) X |
REAL(4) |
GNU Extension |
DGAMMA(X) |
REAL(8) X |
REAL(8) |
GNU Extension |
- See also:
- Logarithm of the Gamma function: LOG_GAMMA