Changeset 9072 for trunk/sources/HeuristicLab.Random

Timestamp:

12/18/12 13:03:12 (11 years ago)

Author:

mkommend

Message:

#1890: Added parameter with default value for source count in RandomEnumerable.SampleRandomWithoutRepetition.

File:

• trunk/sources/HeuristicLab.Random/3.3/RandomEnumerable.cs (modified) (1 diff)

trunk/sources/HeuristicLab.Random/3.3/RandomEnumerable.cs

@@ -121 +121 @@
     /// <param name="random">The random number generator to use, its NextDouble() method must produce values in the range [0;1)</param>
     /// <param name="count">The number of items to be selected.</param>
+    /// <param name="sourceCount">Optional parameter specifying the number of elements in the source enumerations</param>
     /// <returns>A sequence of elements that have been chosen randomly.</returns>
-    public static IEnumerable<T> SampleRandomWithoutRepetition<T>(this IEnumerable<T> source, IRandom random, int count) {
-      int remaining = source.Count();
+    public static IEnumerable<T> SampleRandomWithoutRepetition<T>(this IEnumerable<T> source, IRandom random, int count, int sourceCount = -1) {
+      if (sourceCount == -1) sourceCount = source.Count();
+      int remaining = sourceCount;
       foreach (var item in source) {
         if (random.NextDouble() * remaining < count) {