/* btdtr.c * * Beta distribution * * * * SYNOPSIS: * * double a, b, x, y, btdtr(); * * y = btdtr( a, b, x ); * * * * DESCRIPTION: * * Returns the area from zero to x under the beta density * function: * * * x * - - * | (a+b) | | a-1 b-1 * P(x) = ---------- | t (1-t) dt * - - | | * | (a) | (b) - * 0 * * * This function is identical to the incomplete beta * integral function incbet(a, b, x). * * The complemented function is * * 1 - P(1-x) = incbet( b, a, x ); * * * ACCURACY: * * See incbet.c. * */ /* btdtr() */ /* * Cephes Math Library Release 2.0: April, 1987 * Copyright 1984, 1987, 1995 by Stephen L. Moshier */ #include "mconf.h" double btdtr(a, b, x) double a, b, x; { return (incbet(a, b, x)); }