(tgamma must be thread-safe, signgam is for lgamma* functions)
* SYNOPSIS:
*
* long double x, y, tgammal();
* SYNOPSIS:
*
* long double x, y, tgammal();
* DESCRIPTION:
*
* Returns gamma function of the argument. The result is
* DESCRIPTION:
*
* Returns gamma function of the argument. The result is
- * correctly signed, and the sign (+1 or -1) is also
- * returned in a global (extern) variable named signgam.
- * This variable is also filled in by the logarithmic gamma
- * function lgamma().
*
* Arguments |x| <= 13 are reduced by recurrence and the function
* approximated by a rational function of degree 7/8 in the
*
* Arguments |x| <= 13 are reduced by recurrence and the function
* approximated by a rational function of degree 7/8 in the
long double tgammal(long double x)
{
long double p, q, z;
long double tgammal(long double x)
{
long double p, q, z;
if (isnan(x))
return NAN;
if (x == INFINITY)
if (isnan(x))
return NAN;
if (x == INFINITY)
return x - x;
q = fabsl(x);
if (q > 13.0) {
return x - x;
q = fabsl(x);
if (q > 13.0) {
if (q > MAXGAML)
goto goverf;
if (x < 0.0) {
if (q > MAXGAML)
goto goverf;
if (x < 0.0) {
return (x - x) / (x - x);
i = p;
if ((i & 1) == 0)
return (x - x) / (x - x);
i = p;
if ((i & 1) == 0)
z = q - p;
if (z > 0.5L) {
p += 1.0;
z = q - p;
if (z > 0.5L) {
p += 1.0;
z = fabsl(z) * stirf(q);
if (z <= PIL/LDBL_MAX) {
goverf:
z = fabsl(z) * stirf(q);
if (z <= PIL/LDBL_MAX) {
goverf:
- return signgam * INFINITY;
+ return sign * INFINITY;
}
z = PIL/z;
} else {
z = stirf(x);
}
}
z = PIL/z;
} else {
z = stirf(x);
}
p = __polevll(x, P, 7);
q = __polevll(x, Q, 8);
z = z * p / q;
p = __polevll(x, P, 7);
q = __polevll(x, Q, 8);
z = z * p / q;
- if(z < 0)
- signgam = -1;
if (x < 0.0) {
x = -x;
q = z / (x * __polevll(x, SN, 8));
if (x < 0.0) {
x = -x;
q = z / (x * __polevll(x, SN, 8));
} else
q = z / (x * __polevll(x, S, 8));
return q;
} else
q = z / (x * __polevll(x, S, 8));
return q;