From 7ce331c01ce6eb7b3f5c715a38a24359da9c6ee2 Mon Sep 17 00:00:00 2001 From: Eric Andersen Date: Thu, 22 Nov 2001 14:04:29 +0000 Subject: Totally rework the math library, this time based on the MacOs X math library (which is itself based on the math lib from FreeBSD). -Erik --- libm/double/chdtr.c | 200 ---------------------------------------------------- 1 file changed, 200 deletions(-) delete mode 100644 libm/double/chdtr.c (limited to 'libm/double/chdtr.c') diff --git a/libm/double/chdtr.c b/libm/double/chdtr.c deleted file mode 100644 index a29da7535..000000000 --- a/libm/double/chdtr.c +++ /dev/null @@ -1,200 +0,0 @@ -/* chdtr.c - * - * Chi-square distribution - * - * - * - * SYNOPSIS: - * - * double df, x, y, chdtr(); - * - * y = chdtr( df, x ); - * - * - * - * DESCRIPTION: - * - * Returns the area under the left hand tail (from 0 to x) - * of the Chi square probability density function with - * v degrees of freedom. - * - * - * inf. - * - - * 1 | | v/2-1 -t/2 - * P( x | v ) = ----------- | t e dt - * v/2 - | | - * 2 | (v/2) - - * x - * - * where x is the Chi-square variable. - * - * The incomplete gamma integral is used, according to the - * formula - * - * y = chdtr( v, x ) = igam( v/2.0, x/2.0 ). - * - * - * The arguments must both be positive. - * - * - * - * ACCURACY: - * - * See igam(). - * - * ERROR MESSAGES: - * - * message condition value returned - * chdtr domain x < 0 or v < 1 0.0 - */ - /* chdtrc() - * - * Complemented Chi-square distribution - * - * - * - * SYNOPSIS: - * - * double v, x, y, chdtrc(); - * - * y = chdtrc( v, x ); - * - * - * - * DESCRIPTION: - * - * Returns the area under the right hand tail (from x to - * infinity) of the Chi square probability density function - * with v degrees of freedom: - * - * - * inf. - * - - * 1 | | v/2-1 -t/2 - * P( x | v ) = ----------- | t e dt - * v/2 - | | - * 2 | (v/2) - - * x - * - * where x is the Chi-square variable. - * - * The incomplete gamma integral is used, according to the - * formula - * - * y = chdtr( v, x ) = igamc( v/2.0, x/2.0 ). - * - * - * The arguments must both be positive. - * - * - * - * ACCURACY: - * - * See igamc(). - * - * ERROR MESSAGES: - * - * message condition value returned - * chdtrc domain x < 0 or v < 1 0.0 - */ - /* chdtri() - * - * Inverse of complemented Chi-square distribution - * - * - * - * SYNOPSIS: - * - * double df, x, y, chdtri(); - * - * x = chdtri( df, y ); - * - * - * - * - * DESCRIPTION: - * - * Finds the Chi-square argument x such that the integral - * from x to infinity of the Chi-square density is equal - * to the given cumulative probability y. - * - * This is accomplished using the inverse gamma integral - * function and the relation - * - * x/2 = igami( df/2, y ); - * - * - * - * - * ACCURACY: - * - * See igami.c. - * - * ERROR MESSAGES: - * - * message condition value returned - * chdtri domain y < 0 or y > 1 0.0 - * v < 1 - * - */ - -/* chdtr() */ - - -/* -Cephes Math Library Release 2.8: June, 2000 -Copyright 1984, 1987, 2000 by Stephen L. Moshier -*/ - -#include -#ifdef ANSIPROT -extern double igamc ( double, double ); -extern double igam ( double, double ); -extern double igami ( double, double ); -#else -double igamc(), igam(), igami(); -#endif - -double chdtrc(df,x) -double df, x; -{ - -if( (x < 0.0) || (df < 1.0) ) - { - mtherr( "chdtrc", DOMAIN ); - return(0.0); - } -return( igamc( df/2.0, x/2.0 ) ); -} - - - -double chdtr(df,x) -double df, x; -{ - -if( (x < 0.0) || (df < 1.0) ) - { - mtherr( "chdtr", DOMAIN ); - return(0.0); - } -return( igam( df/2.0, x/2.0 ) ); -} - - - -double chdtri( df, y ) -double df, y; -{ -double x; - -if( (y < 0.0) || (y > 1.0) || (df < 1.0) ) - { - mtherr( "chdtri", DOMAIN ); - return(0.0); - } - -x = igami( 0.5 * df, y ); -return( 2.0 * x ); -} -- cgit v1.2.3