tgamma(), tgammaf(), tgammal() — Calculate gamma function
Standards
Standards / Extensions | C or C++ | Dependencies |
---|---|---|
C99 |
both | z/OS V1R5 |
Format
#define _ISOC99_SOURCE
#include <math.h>
double tgamma(double x);
float tgammaf(float x);
long double tgammal(long double x);
C++
TR1 C99
#define _TR1_C99
#include <math.h>
float tgamma(float x);
long double tgamma(long double x);
General description
The tgamma functions
compute the gamma function of x. A domain
error occurs if x is a negative integer or when x is zero and the
result cannot be represented. A range error occurs if the magnitude
of x is too large or too small.
Note: The
following table shows the viable formats for these functions. See IEEE binary floating-point for more information about IEEE
Binary Floating-Point.
Function | Hex | IEEE |
---|---|---|
tgamma | X | X |
tgammaf | X | X |
tgammal | X | X |
Special behavior for IEEE: A pole error occurs if the input of tgammaf is 0 and sets errno to ERANGE. A domain error occurs if the input of tgammaf is a negative integer and sets errno to EDOM.
Returned value
The tgamma functions return G(x).