Documentation

sort/sort.go

@@ -1,11 +1,15 @@
+/*
+This package provides a few functions to sort int arrays.
+	* Sort by values of another array
+	* Return permutation allowing to sort input array (like R order() function)
+Inspired from https://stackoverflow.com/questions/42707252/
+*/
 package sort
 
 import (
 	"sort"
 )
 
-// See https://stackoverflow.com/questions/42707252/
-
 type by struct {
 	Indices []int
 	Values  []int
@@ -18,10 +22,11 @@ func (b by) Swap(i, j int) {
 	b.Values[i], b.Values[j] = b.Values[j], b.Values[i]
 }
 
-/*
-Sorts "toSort" array according to "byValues" Array.
-Only "toSort" array is modified.  "byValues" array is not modified.
-*/
+// Sorts "toSort" array according to "byValues" Array.
+//	* "toSort" array is modified after the function.
+//	* "byValues" array is not modified.
+//
+// The sort may be in decreasing order.
 func SortIntBy(toSort []int, byValues []int, decreasing bool) {
 	valuescopy := make([]int, len(byValues))
 	copy(valuescopy, byValues)
@@ -32,16 +37,16 @@ func SortIntBy(toSort []int, byValues []int, decreasing bool) {
 	}
 }
 
-/*
-Returns sorted indices by values
-Example:
-Input: [10,20,30,80,50]
-Outpt: [0,1,2,4,3]
-To range over the sorted array :
-for _,ord := range output {
-    input[ord]
-}
-*/
+// Returns reordered indices (permutation) by values (like order() R function).
+// It may be in decreasing order.
+//
+// Example:
+//	input := []int{10,20,30,80,50}
+//	output := OrderInt(input) // {0,1,2,4,3}
+//	// To iterate over the sorted array :
+// 	for _,ord := range output {
+// 	    input[ord]
+// 	}
 func OrderInt(values []int, decreasing bool) []int {
 	// init initial order indices
 	indices := make([]int, len(values))