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authorEric Andersen <andersen@codepoet.org>2001-05-10 00:40:28 +0000
committerEric Andersen <andersen@codepoet.org>2001-05-10 00:40:28 +0000
commit1077fa4d772832f77a677ce7fb7c2d513b959e3f (patch)
tree579bee13fb0b58d2800206366ec2caecbb15f3fc /libm/double/btdtr.c
parent22358dd7ce7bb49792204b698f01a6f69b9c8e08 (diff)
uClibc now has a math library. muahahahaha!
-Erik
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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 ) );
+}