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/***************************************************************
    $Id: gexp.c,v 1.13 2015/12/14 01:14:25 uratec Exp $

    Generalized Exponential Function (real argument)

    double gexp(r, x)

    double r : gamma
    double x : argument

*****************************************************************/

#include <math.h>

double gexp(const double r, const double x)
{
   if (r == 0.0) {
      return (exp(x));
   } else {
      if (r < 0.0)
         return (pow(1 / (1 + r * x), -1 / r));
      else
         return (pow(1 + r * x, 1 / r));
   }
}
