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@@ -21,7 +21,6 @@
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* SYNOPSIS:
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*
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* long double x, y, tgammal();
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- * extern int signgam;
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*
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* y = tgammal( x );
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*
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@@ -29,10 +28,7 @@
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* DESCRIPTION:
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*
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* Returns gamma function of the argument. The result is
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- * correctly signed, and the sign (+1 or -1) is also
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- * returned in a global (extern) variable named signgam.
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- * This variable is also filled in by the logarithmic gamma
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- * function lgamma().
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+ * correctly signed.
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*
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* Arguments |x| <= 13 are reduced by recurrence and the function
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* approximated by a rational function of degree 7/8 in the
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@@ -209,9 +205,8 @@ static long double stirf(long double x)
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long double tgammal(long double x)
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{
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long double p, q, z;
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- int i;
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+ int i, sign;
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- signgam = 1;
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if (isnan(x))
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return NAN;
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if (x == INFINITY)
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@@ -220,6 +215,7 @@ long double tgammal(long double x)
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return x - x;
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q = fabsl(x);
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if (q > 13.0) {
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+ sign = 1;
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if (q > MAXGAML)
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goto goverf;
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if (x < 0.0) {
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@@ -228,7 +224,7 @@ long double tgammal(long double x)
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return (x - x) / (x - x);
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i = p;
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if ((i & 1) == 0)
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- signgam = -1;
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+ sign = -1;
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z = q - p;
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if (z > 0.5L) {
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p += 1.0;
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@@ -238,13 +234,13 @@ long double tgammal(long double x)
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z = fabsl(z) * stirf(q);
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if (z <= PIL/LDBL_MAX) {
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goverf:
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- return signgam * INFINITY;
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+ return sign * INFINITY;
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}
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z = PIL/z;
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} else {
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z = stirf(x);
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}
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- return signgam * z;
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+ return sign * z;
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}
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z = 1.0;
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@@ -269,8 +265,6 @@ goverf:
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p = __polevll(x, P, 7);
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q = __polevll(x, Q, 8);
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z = z * p / q;
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- if(z < 0)
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- signgam = -1;
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return z;
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small:
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@@ -279,7 +273,6 @@ small:
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if (x < 0.0) {
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x = -x;
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q = z / (x * __polevll(x, SN, 8));
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- signgam = -1;
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} else
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q = z / (x * __polevll(x, S, 8));
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return q;
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