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/*
* ====================================================
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
*
* Developed at SunPro, a Sun Microsystems, Inc. business.
* Permission to use, copy, modify, and distribute this
* software is freely granted, provided that this notice
* is preserved.
* ====================================================
*/
/* double gamma(double x)
* Return the logarithm of the Gamma function of x.
*
* Method: call gamma_r
*/
#include <math.h>
#include "math_private.h"
double gamma(double x)
{
#ifdef _IEEE_LIBM
return __ieee754_lgamma_r(x, &signgam);
#else
double y = __ieee754_lgamma_r(x, &signgam);
if (_LIB_VERSION == _IEEE_)
return y;
if (!isfinite(y) && isfinite(x)) {
if (floor(x) == x && x <= 0.0)
return __kernel_standard(x, x, 41); /* gamma pole */
return __kernel_standard(x, x, 40); /* gamma overflow */
}
return y;
#endif
}
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