fixed dependencies

vendor/gonum.org/v1/gonum/mathext/betainc.go

@@ -0,0 +1,33 @@
+// Copyright ©2016 The Gonum Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package mathext
+
+import "gonum.org/v1/gonum/mathext/internal/cephes"
+
+// RegIncBeta returns the value of the regularized incomplete beta function
+// I(x;a,b). It is defined as
+//
+//	I(x;a,b) = B(x;a,b) / B(a,b)
+//	         = Γ(a+b) / (Γ(a)*Γ(b)) * int_0^x u^(a-1) * (1-u)^(b-1) du.
+//
+// The domain of definition is 0 <= x <= 1, and the parameters a and b must be positive.
+// For other values of x, a, and b RegIncBeta will panic.
+func RegIncBeta(a, b float64, x float64) float64 {
+	return cephes.Incbet(a, b, x)
+}
+
+// InvRegIncBeta computes the inverse of the regularized incomplete beta function.
+// It returns the x for which
+//
+//	y = I(x;a,b)
+//
+// The domain of definition is 0 <= y <= 1, and the parameters a and b must be
+// positive. For other values of x, a, and b InvRegIncBeta will panic.
+func InvRegIncBeta(a, b float64, y float64) float64 {
+	if y < 0 || 1 < y {
+		panic("mathext: parameter out of range")
+	}
+	return cephes.Incbi(a, b, y)
+}