Merge pull request #201 from Bytom/v0.1

[bytom/vapor.git] / vendor / gonum.org / v1 / gonum / lapack / gonum / dlartg.go

diff --git a/vendor/gonum.org/v1/gonum/lapack/gonum/dlartg.go b/vendor/gonum.org/v1/gonum/lapack/gonum/dlartg.go
deleted file mode 100644 (file)
index ad64546..0000000
--- a/vendor/gonum.org/v1/gonum/lapack/gonum/dlartg.go
+++ /dev/null
@@ -1,80 +0,0 @@
-// Copyright ©2015 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 gonum
-
-import "math"
-
-// Dlartg generates a plane rotation so that
-//  [ cs sn] * [f] = [r]
-//  [-sn cs]   [g] = [0]
-// This is a more accurate version of BLAS drotg, with the other differences that
-// if g = 0, then cs = 1 and sn = 0, and if f = 0 and g != 0, then cs = 0 and sn = 1.
-// If abs(f) > abs(g), cs will be positive.
-//
-// Dlartg is an internal routine. It is exported for testing purposes.
-func (impl Implementation) Dlartg(f, g float64) (cs, sn, r float64) {
-       safmn2 := math.Pow(dlamchB, math.Trunc(math.Log(dlamchS/dlamchE)/math.Log(dlamchB)/2))
-       safmx2 := 1 / safmn2
-       if g == 0 {
-               cs = 1
-               sn = 0
-               r = f
-               return cs, sn, r
-       }
-       if f == 0 {
-               cs = 0
-               sn = 1
-               r = g
-               return cs, sn, r
-       }
-       f1 := f
-       g1 := g
-       scale := math.Max(math.Abs(f1), math.Abs(g1))
-       if scale >= safmx2 {
-               var count int
-               for {
-                       count++
-                       f1 *= safmn2
-                       g1 *= safmn2
-                       scale = math.Max(math.Abs(f1), math.Abs(g1))
-                       if scale < safmx2 {
-                               break
-                       }
-               }
-               r = math.Sqrt(f1*f1 + g1*g1)
-               cs = f1 / r
-               sn = g1 / r
-               for i := 0; i < count; i++ {
-                       r *= safmx2
-               }
-       } else if scale <= safmn2 {
-               var count int
-               for {
-                       count++
-                       f1 *= safmx2
-                       g1 *= safmx2
-                       scale = math.Max(math.Abs(f1), math.Abs(g1))
-                       if scale >= safmn2 {
-                               break
-                       }
-               }
-               r = math.Sqrt(f1*f1 + g1*g1)
-               cs = f1 / r
-               sn = g1 / r
-               for i := 0; i < count; i++ {
-                       r *= safmn2
-               }
-       } else {
-               r = math.Sqrt(f1*f1 + g1*g1)
-               cs = f1 / r
-               sn = g1 / r
-       }
-       if math.Abs(f) > math.Abs(g) && cs < 0 {
-               cs *= -1
-               sn *= -1
-               r *= -1
-       }
-       return cs, sn, r
-}