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authorEric Andersen <andersen@codepoet.org>2001-11-22 14:04:29 +0000
committerEric Andersen <andersen@codepoet.org>2001-11-22 14:04:29 +0000
commit7ce331c01ce6eb7b3f5c715a38a24359da9c6ee2 (patch)
tree3a7e8476e868ae15f4da1b7ce26b2db6f434468c /libm/float/chdtrf.c
parentc117dd5fb183afb1a4790a6f6110d88704be6bf8 (diff)
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
Diffstat (limited to 'libm/float/chdtrf.c')
-rw-r--r--libm/float/chdtrf.c210
1 files changed, 0 insertions, 210 deletions
diff --git a/libm/float/chdtrf.c b/libm/float/chdtrf.c
deleted file mode 100644
index 53bd3d961..000000000
--- a/libm/float/chdtrf.c
+++ /dev/null
@@ -1,210 +0,0 @@
-/* chdtrf.c
- *
- * Chi-square distribution
- *
- *
- *
- * SYNOPSIS:
- *
- * float df, x, y, chdtrf();
- *
- * y = chdtrf( 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:
- *
- * Relative error:
- * arithmetic domain # trials peak rms
- * IEEE 0,100 5000 3.2e-5 5.0e-6
- *
- * ERROR MESSAGES:
- *
- * message condition value returned
- * chdtrf domain x < 0 or v < 1 0.0
- */
- /* chdtrcf()
- *
- * Complemented Chi-square distribution
- *
- *
- *
- * SYNOPSIS:
- *
- * float v, x, y, chdtrcf();
- *
- * y = chdtrcf( 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:
- *
- * Relative error:
- * arithmetic domain # trials peak rms
- * IEEE 0,100 5000 2.7e-5 3.2e-6
- *
- * ERROR MESSAGES:
- *
- * message condition value returned
- * chdtrc domain x < 0 or v < 1 0.0
- */
- /* chdtrif()
- *
- * Inverse of complemented Chi-square distribution
- *
- *
- *
- * SYNOPSIS:
- *
- * float df, x, y, chdtrif();
- *
- * x = chdtrif( 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:
- *
- * Relative error:
- * arithmetic domain # trials peak rms
- * IEEE 0,100 10000 2.2e-5 8.5e-7
- *
- * ERROR MESSAGES:
- *
- * message condition value returned
- * chdtri domain y < 0 or y > 1 0.0
- * v < 1
- *
- */
-
-/* chdtr() */
-
-
-/*
-Cephes Math Library Release 2.2: July, 1992
-Copyright 1984, 1987, 1992 by Stephen L. Moshier
-Direct inquiries to 30 Frost Street, Cambridge, MA 02140
-*/
-
-#include <math.h>
-
-#ifdef ANSIC
-float igamcf(float, float), igamf(float, float), igamif(float, float);
-#else
-float igamcf(), igamf(), igamif();
-#endif
-
-float chdtrcf(float dff, float xx)
-{
-float df, x;
-
-df = dff;
-x = xx;
-
-if( (x < 0.0) || (df < 1.0) )
- {
- mtherr( "chdtrcf", DOMAIN );
- return(0.0);
- }
-return( igamcf( 0.5*df, 0.5*x ) );
-}
-
-
-float chdtrf(float dff, float xx)
-{
-float df, x;
-
-df = dff;
-x = xx;
-if( (x < 0.0) || (df < 1.0) )
- {
- mtherr( "chdtrf", DOMAIN );
- return(0.0);
- }
-return( igamf( 0.5*df, 0.5*x ) );
-}
-
-
-float chdtrif( float dff, float yy )
-{
-float y, df, x;
-
-y = yy;
-df = dff;
-if( (y < 0.0) || (y > 1.0) || (df < 1.0) )
- {
- mtherr( "chdtrif", DOMAIN );
- return(0.0);
- }
-
-x = igamif( 0.5 * df, y );
-return( 2.0 * x );
-}