### gamma -- Gamma Function

Format

>     #include <math.h>
>     double gamma(double x);

Language Level: Extension
gamma computes ln( |G(x)| ), where

Return Value
gamma returns the value of ln(|G(x)|). If x is a negative value, errno is set to EDOM. If the result causes an overflow, gamma returns HUGE_VAL and sets errno to ERANGE.

Example
This example uses gamma to calculate ln(|G(x)|), where x = 42.

    #include <math.h>
    #include <stdio.h>

    int main(void)
    {
       double x=42, g_at_x;

       g_at_x = exp(gamma(x));       /* g_at_x = 3.345253e+49 */
       printf ("The value of G(%4.2lf) is %7.2e\n", x, g_at_x);

       /********************************************************
          The output should be:

          The value of G(42.00) is 3.35e+49
       ********************************************************/
    }

Bessel Functions -- Solve Differential Equations
erf - erfc -- Calculate Error Functions
<math.h>