go: implement RandomSearch wip2

* perform RandomSearch with each of the benchmarking functions for a
  prescribed number of iterations

left to do:
* saving the solution
* parsing the solution to a table
* parsing the solution to generate graphs

* follow-up of b3787da640

algo/randomSearch.go

@@ -46,7 +46,6 @@ func genValsRandomSearch(dimens uint, vals []float64, uniform *distuv.Uniform) {
 // * f string: name of the bench func to optimise (see bench/functions)
 // * min/max float64: the upper/lower limit of the uniform distribution span,
 // which is relevant to the objective function.
-// nolint
 func singleRandomSearch(dimens uint, f string, min, max float64) ([]float64, float64) {
 	vals := make([]float64, dimens)
 
@@ -73,6 +72,8 @@ func singleRandomSearch(dimens uint, f string, min, max float64) ([]float64, flo
 	return vals, res
 }
 
+// TODO(me): split this up
+// nolint: gocognit
 func RandomSearch(fes uint) {
 	if fes == 0 {
 		log.Fatalln(" random search: fes set to 0, bailing")
@@ -90,47 +91,93 @@ func RandomSearch(fes uint) {
 
 	var resultsDeJong2nd Values
 
+	var bestResultsSchwefel []float64
+
+	var bestResultsDeJong1st []float64
+
+	var bestResultsDeJong2nd []float64
+
 	// iterations needed to establish a minimal viable statistical baseline
 	minIters := 30
 
 	for _, dimens := range bench.Dimensions {
 		for i := 0; i < minIters; i++ {
-			// run Schwefel.
-			v, r := singleRandomSearch(
-				dimens,
-				bench.Functions[0],
-				bench.SchwefelParams.Min(),
-				bench.SchwefelParams.Max(),
-			)
-			valsSchwefel = append(valsSchwefel, v)
-			resultsSchwefel = append(resultsSchwefel, r)
+			var bestResult float64
 
-			// run De Jong 1st.
-			vDJ1, rDJ1 := singleRandomSearch(
-				dimens,
-				bench.Functions[1],
-				bench.DeJong1Params.Min(),
-				bench.DeJong1Params.Max(),
-			)
-			valsDeJong1st = append(valsDeJong1st, vDJ1)
-			resultsDeJong1st = append(resultsDeJong1st, rDJ1)
-			// run De Jong 2nd.
-			vDJ2, rDJ2 := singleRandomSearch(
-				dimens,
-				bench.Functions[2],
-				bench.DeJong2Params.Min(),
-				bench.DeJong2Params.Max(),
-			)
-			valsDeJong2nd = append(valsDeJong2nd, vDJ2)
-			resultsDeJong2nd = append(resultsDeJong2nd, rDJ2)
+			for j := 0; j < int(fes); j++ {
+				// run Schwefel.
+				v, r := singleRandomSearch(
+					dimens,
+					bench.Functions[0],
+					bench.SchwefelParams.Min(),
+					bench.SchwefelParams.Max(),
+				)
+				valsSchwefel = append(valsSchwefel, v)
+				resultsSchwefel = append(resultsSchwefel, r)
+
+				switch j {
+				// first iteration
+				case 0:
+					bestResult = r
+				default:
+					// any other than the first iteration and a better solution
+					if r < bestResult {
+						bestResult = r
+					}
+				}
+
+				bestResultsSchwefel = append(bestResultsSchwefel, bestResult)
+			}
+
+			for k := 0; k < int(fes); k++ {
+				// run De Jong 1st.
+				v, r := singleRandomSearch(
+					dimens,
+					bench.Functions[1],
+					bench.DeJong1Params.Min(),
+					bench.DeJong1Params.Max(),
+				)
+				valsDeJong1st = append(valsDeJong1st, v)
+				resultsDeJong1st = append(resultsDeJong1st, r)
+
+				// first iteration or better solution
+				if k == 0 || r < bestResult {
+					bestResult = r
+				}
+
+				bestResultsDeJong1st = append(bestResultsDeJong1st, bestResult)
+			}
+
+			for l := 0; l < int(fes); l++ {
+				// run De Jong 2nd.
+				v, r := singleRandomSearch(
+					dimens,
+					bench.Functions[2],
+					bench.DeJong2Params.Min(),
+					bench.DeJong2Params.Max(),
+				)
+				valsDeJong2nd = append(valsDeJong2nd, v)
+				resultsDeJong2nd = append(resultsDeJong2nd, r)
+
+				// first iteration or better solution
+				if l == 0 || r < bestResult {
+					bestResult = r
+				}
+
+				bestResultsDeJong2nd = append(bestResultsDeJong2nd, bestResult)
+			}
 		}
 	}
 
-	fmt.Fprintln(os.Stderr, "vals schw:", valsSchwefel)
-	fmt.Fprintln(os.Stderr, "vals dj1", valsDeJong1st)
-	fmt.Fprintln(os.Stderr, "vals dj2", valsDeJong2nd)
+	fmt.Fprintln(os.Stderr, "vals schw len", len(valsSchwefel))
+	fmt.Fprintln(os.Stderr, "vals dj1 len", len(valsDeJong1st))
+	fmt.Fprintln(os.Stderr, "vals dj2 len", len(valsDeJong2nd))
 
-	fmt.Fprintln(os.Stderr, "res schw:", resultsSchwefel)
-	fmt.Fprintln(os.Stderr, "res dj1", resultsDeJong1st)
-	fmt.Fprintln(os.Stderr, "res dj2", resultsDeJong2nd)
+	fmt.Fprintln(os.Stderr, "res schw len", len(resultsSchwefel))
+	fmt.Fprintln(os.Stderr, "res dj1 len", len(resultsDeJong1st))
+	fmt.Fprintln(os.Stderr, "res dj2 len", len(resultsDeJong2nd))
+
+	fmt.Fprintln(os.Stderr, "best res schw len", len(bestResultsSchwefel))
+	fmt.Fprintln(os.Stderr, "best res dj1 len", len(bestResultsDeJong1st))
+	fmt.Fprintln(os.Stderr, "best res dj2 len", len(bestResultsDeJong2nd))
 }