go: change Functions var to a string-func map

algo/randomSearch.go

@@ -44,31 +44,20 @@ func genValsRandomSearch(dimens uint, vals []float64, uniform *distuv.Uniform) {
 // singleRandomSearch performs a single iteration of the 'RandomSearch' algorithm.
 // it takes a couple of arguments:
 // * dimens uint: number of dimensions of the objective function
-// * f string: name of the bench func to optimise (see bench/functions)
+// * f func([]float64) float64: bench func to execute (see Functions map in
+//   bench/functions.go)
 // * min/max float64: the upper/lower limit of the uniform distribution span,
 // which is relevant to the objective function.
-func singleRandomSearch(dimens uint, f string, min, max float64) ([]float64, float64) {
+func singleRandomSearch(dimens uint, f func([]float64) float64, min, max float64) ([]float64, float64) {
 	vals := make([]float64, dimens)
 
-	var res float64
-
 	// create a continuous uniform distribution representation within min/max bounds
 	uniformDist := distuv.Uniform{Min: min, Max: max}
 
 	genValsRandomSearch(dimens, vals, &uniformDist)
 
-	// result of the benchmarking function computation over vals
-	switch f {
-	// Schwefel
-	case bench.Functions[0]:
-		res = bench.Schwefel(vals)
-	// "DeJong1st"
-	case bench.Functions[1]:
-		res = bench.DeJong1st(vals)
-	// "DeJong2nd"
-	case bench.Functions[2]:
-		res = bench.DeJong2nd(vals)
-	}
+	// result of the bench function.
+	res := f(vals)
 
 	return vals, res
 }
@@ -135,7 +124,7 @@ func RandomSearch(fes uint) {
 				// run Schwefel.
 				v, r := singleRandomSearch(
 					dimens,
-					bench.Functions[0],
+					bench.Functions["Schwefel"],
 					bench.SchwefelParams.Min(),
 					bench.SchwefelParams.Max(),
 				)
@@ -173,7 +162,7 @@ func RandomSearch(fes uint) {
 				// run De Jong 1st.
 				v, r := singleRandomSearch(
 					dimens,
-					bench.Functions[1],
+					bench.Functions["De Jong 1st"],
 					bench.DeJong1Params.Min(),
 					bench.DeJong1Params.Max(),
 				)
@@ -205,7 +194,7 @@ func RandomSearch(fes uint) {
 				// run De Jong 2nd.
 				v, r := singleRandomSearch(
 					dimens,
-					bench.Functions[2],
+					bench.Functions["De Jong 2nd"],
 					bench.DeJong2Params.Min(),
 					bench.DeJong2Params.Max(),
 				)

bench/functions.go

@@ -5,7 +5,13 @@ package bench
 
 import "math"
 
-var Functions = []string{"Schwefel", "De Jong 1st", "De Jong 2nd"}
+// Functions is a string-func map of function names and specific bench funcs
+// for easier iterable access.
+var Functions = map[string]func([]float64) float64{
+	"Schwefel":    Schwefel,
+	"De Jong 1st": DeJong1st,
+	"De Jong 2nd": DeJong2nd,
+}
 
 // Schwefel computes a value of the Schwefel function for x.
 func Schwefel(x []float64) float64 {