升级流程引擎配置文件版本

vendor/github.com/montanaflynn/stats/sample.go

@@ -0,0 +1,44 @@
+package stats
+
+import "math/rand"
+
+// Sample returns sample from input with replacement or without
+func Sample(input Float64Data, takenum int, replacement bool) ([]float64, error) {
+
+	if input.Len() == 0 {
+		return nil, EmptyInput
+	}
+
+	length := input.Len()
+	if replacement {
+
+		result := Float64Data{}
+		rand.Seed(unixnano())
+
+		// In every step, randomly take the num for
+		for i := 0; i < takenum; i++ {
+			idx := rand.Intn(length)
+			result = append(result, input[idx])
+		}
+
+		return result, nil
+
+	} else if !replacement && takenum <= length {
+
+		rand.Seed(unixnano())
+
+		// Get permutation of number of indexies
+		perm := rand.Perm(length)
+		result := Float64Data{}
+
+		// Get element of input by permutated index
+		for _, idx := range perm[0:takenum] {
+			result = append(result, input[idx])
+		}
+
+		return result, nil
+
+	}
+
+	return nil, BoundsErr
+}