1 files changed, 64 insertions, 0 deletions
diff --git a/libm/double/btdtr.c b/libm/double/btdtr.c
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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 2.8:  June, 2000
+Copyright 1984, 1987, 1995, 2000 by Stephen L. Moshier
+*/
+#include <math.h>
+#ifdef ANSIPROT
+extern double incbet ( double, double, double );
+#else
+double incbet();
+#endif
+
+double btdtr( a, b, x )
+double a, b, x;
+{
+
+return( incbet( a, b, x ) );
+}