fixed dependencies

vendor/gonum.org/v1/gonum/optimize/guessandcheck.go

@@ -0,0 +1,92 @@
+// 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 optimize
+
+import (
+	"math"
+
+	"gonum.org/v1/gonum/stat/distmv"
+)
+
+var _ Method = (*GuessAndCheck)(nil)
+
+// GuessAndCheck is a global optimizer that evaluates the function at random
+// locations. Not a good optimizer, but useful for comparison and debugging.
+type GuessAndCheck struct {
+	Rander distmv.Rander
+
+	bestF float64
+	bestX []float64
+}
+
+func (*GuessAndCheck) Uses(has Available) (uses Available, err error) {
+	return has.function()
+}
+
+func (g *GuessAndCheck) Init(dim, tasks int) int {
+	if dim <= 0 {
+		panic(nonpositiveDimension)
+	}
+	if tasks < 0 {
+		panic(negativeTasks)
+	}
+	g.bestF = math.Inf(1)
+	g.bestX = resize(g.bestX, dim)
+	return tasks
+}
+
+func (g *GuessAndCheck) sendNewLoc(operation chan<- Task, task Task) {
+	g.Rander.Rand(task.X)
+	task.Op = FuncEvaluation
+	operation <- task
+}
+
+func (g *GuessAndCheck) updateMajor(operation chan<- Task, task Task) {
+	// Update the best value seen so far, and send a MajorIteration.
+	if task.F < g.bestF {
+		g.bestF = task.F
+		copy(g.bestX, task.X)
+	} else {
+		task.F = g.bestF
+		copy(task.X, g.bestX)
+	}
+	task.Op = MajorIteration
+	operation <- task
+}
+
+func (g *GuessAndCheck) Run(operation chan<- Task, result <-chan Task, tasks []Task) {
+	// Send initial tasks to evaluate
+	for _, task := range tasks {
+		g.sendNewLoc(operation, task)
+	}
+
+	// Read from the channel until PostIteration is sent.
+Loop:
+	for {
+		task := <-result
+		switch task.Op {
+		default:
+			panic("unknown operation")
+		case PostIteration:
+			break Loop
+		case MajorIteration:
+			g.sendNewLoc(operation, task)
+		case FuncEvaluation:
+			g.updateMajor(operation, task)
+		}
+	}
+
+	// PostIteration was sent. Update the best new values.
+	for task := range result {
+		switch task.Op {
+		default:
+			panic("unknown operation")
+		case MajorIteration:
+		case FuncEvaluation:
+			g.updateMajor(operation, task)
+		}
+	}
+	close(operation)
+}