From d2802ec8c88ac19590741df9cd33a5556ae9c93e Mon Sep 17 00:00:00 2001
From: Philipp Altmann <philippaltmann@deap.io>
Date: Sun, 27 Aug 2017 18:18:14 +0200
Subject: [PATCH] Corrected implementation and Added tests for Rosenbrock

---
 Rosenbrock/Rosenbrock.go      |  9 +++----
 Rosenbrock/Rosenbrock_test.go | 46 +++++++++++++++++++++++++++++++++++
 2 files changed, 49 insertions(+), 6 deletions(-)
 create mode 100644 Rosenbrock/Rosenbrock_test.go

diff --git a/Rosenbrock/Rosenbrock.go b/Rosenbrock/Rosenbrock.go
index db625e8..7943e52 100644
--- a/Rosenbrock/Rosenbrock.go
+++ b/Rosenbrock/Rosenbrock.go
@@ -12,12 +12,9 @@ func EvaluateFitness(values []float64) (fitness float64) {
 	for i := 0; i < len(values)-1; i++ {
 		xi := values[i]
 		xj := values[i+1]
-		fitness += (math.Pow(
-			(math.Pow(xi, 2) + math.Pow(xj, 2)), 0.25)) *
-			(math.Pow(
-				math.Sin(
-					50*math.Pow(
-						(math.Pow(xi, 2)+math.Pow(xj, 2)), 0.1)), 2) + 1)
+		fitness += math.Pow(
+			1-xi, 2) + 100*math.Pow(
+			(xj-math.Pow(xi, 2)), 2)
 	}
 	return
 }
diff --git a/Rosenbrock/Rosenbrock_test.go b/Rosenbrock/Rosenbrock_test.go
new file mode 100644
index 0000000..336ecfc
--- /dev/null
+++ b/Rosenbrock/Rosenbrock_test.go
@@ -0,0 +1,46 @@
+package Rosenbrock
+
+import (
+	"math/rand"
+	"testing"
+)
+
+func TestEvaluateFitness(t *testing.T) {
+	//Testing if minimum is calculated as defined
+	testValues := make([]float64, 32)
+	for i := 0; i < len(testValues); i++ {
+		testValues[i] = 1
+	}
+	testResult := EvaluateFitness(testValues)
+	if testResult != 0 {
+		t.Error("Minimum not 0\n")
+		t.Error(testResult)
+		t.Fail()
+	}
+}
+
+func benchmarkRosenbrock(b *testing.B, dimensions int) {
+	var vals []float64
+	for v := 0; v < dimensions; v++ {
+		vals = append(vals, rand.Float64()*200-100)
+	}
+
+	for n := 0; n < b.N; n++ {
+		EvaluateFitness(vals)
+	}
+}
+func BenchmarkRosenbrock4(b *testing.B)   { benchmarkRosenbrock(b, 4) }
+func BenchmarkRosenbrock8(b *testing.B)   { benchmarkRosenbrock(b, 8) }
+func BenchmarkRosenbrock16(b *testing.B)  { benchmarkRosenbrock(b, 16) }
+func BenchmarkRosenbrock32(b *testing.B)  { benchmarkRosenbrock(b, 32) }
+func BenchmarkRosenbrock64(b *testing.B)  { benchmarkRosenbrock(b, 64) }
+func BenchmarkRosenbrock128(b *testing.B) { benchmarkRosenbrock(b, 128) }
+
+/*
+BenchmarkRosenbrock4-8     	 5000000	       278 ns/op
+BenchmarkRosenbrock8-8     	 2000000	       624 ns/op
+BenchmarkRosenbrock16-8    	 1000000	      1488 ns/op
+BenchmarkRosenbrock32-8    	  500000	      3110 ns/op
+BenchmarkRosenbrock64-8    	  200000	      6652 ns/op
+BenchmarkRosenbrock128-8   	  100000	     13913 ns/op
+*/