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/* 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));
}
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