3 * Gamma distribution function
9 * double a, b, x, y, gdtr();
11 * y = gdtr( a, b, x );
17 * Returns the integral from zero to x of the gamma probability
29 * The incomplete gamma integral is used, according to the
41 * message condition value returned
42 * gdtr domain x < 0 0.0
47 * Complemented gamma distribution function
53 * double a, b, x, y, gdtrc();
55 * y = gdtrc( a, b, x );
61 * Returns the integral from x to infinity of the gamma
62 * probability density function:
73 * The incomplete gamma integral is used, according to the
85 * message condition value returned
86 * gdtrc domain x < 0 0.0
94 Cephes Math Library Release 2.8: June, 2000
95 Copyright 1984, 1987, 1995, 2000 by Stephen L. Moshier
100 extern double igam ( double, double );
101 extern double igamc ( double, double );
103 double igam(), igamc();
106 double gdtr( a, b, x )
112 mtherr( "gdtr", DOMAIN );
115 return( igam( b, a * x ) );
120 double gdtrc( a, b, x )
126 mtherr( "gdtrc", DOMAIN );
129 return( igamc( b, a * x ) );