double gamma ( double x )
{
double ret;
if ( x<=0.0 )
{
ret = 0.0;
}
#if 0
else if ( x<0.5 )
{
ret = gamma_kernel(x+1.0)/x; /* Puts x in [0.5,1.5) */
}
else if ( x<1.5 )
{
ret = gamma_kernel(x); /* Puts x in [0.5,1.5) */
}
else
{
ret = (x-1.0) * gamma(x-1.0); /* Recurse till x in [0.5,1.5) */
}
#else
else if ( x<1.0 )
double gamma ( double x )
{
double ret;
if ( x<=0.0 )
{
ret = 0.0;
}
else if ( x<1.0 )
{
ret = gamma_kernel(x);
}
else
{
ret = (x-1.0) * gamma(x-1.0);
}
END:
return ret;
}
else if ( x<0.5 )
{
ret = gamma_kernel(x+1.0)/x; /* Puts x in [0.5,1.5) */
}
else if ( x<1.5 )
{
ret = gamma_kernel(x); /* Puts x in [0.5,1.5) */
}
else
{
ret = (x-1.0) * gamma(x-1.0); /* Recurse till x in [0.5,1.5) */
}
#else
else if ( x<1.0 )
{
ret = gamma_kernel(x);
}
else
{
ret = (x-1.0) * gamma(x-1.0);
}
#endif
END:
return ret;
}
double my_pow_f ( double base, double exp )
{
return exponential ( exp * natural_log(base) );
}
