Changeset 16252

Timestamp:

10/24/18 10:45:47 (6 years ago)

Author:

bburlacu

Message:

#2950: Minor refactor of HashExtensions.cs to allow method chaining. Minor refactor in SymbolicExpressionTreeHash.cs.

Location:

trunk/HeuristicLab.Problems.DataAnalysis.Symbolic/3.4/Hashing

Files:

• HashExtensions.cs (modified) (8 diffs)
• SymbolicExpressionTreeHash.cs (modified) (2 diffs)

trunk/HeuristicLab.Problems.DataAnalysis.Symbolic/3.4/Hashing/HashExtensions.cs

@@ -91 +91 @@
 
     public static HashNode<T>[] Simplify<T>(this HashNode<T>[] nodes) where T : class {
-      var reduced = nodes.Reduce();
-      reduced.Sort();
+      var reduced = nodes.UpdateNodeSizes().Reduce().Sort();
 
       for (int i = 0; i < reduced.Length; ++i) {
@@ -117 +116 @@
         }
       }
-      simplified.UpdateNodeSizes();
-      simplified.Sort();
-      return simplified;
-    }
-
-    public static void Sort<T>(this HashNode<T>[] nodes) where T : class {
+      return simplified.UpdateNodeSizes().Sort();
+    }
+
+    public static HashNode<T>[] Sort<T>(this HashNode<T>[] nodes) where T : class {
       for (int i = 0; i < nodes.Length; ++i) {
         var node = nodes[i];
@@ -155 +152 @@
         node.CalculatedHashValue = nodes.ComputeHash(i);
       }
+      return nodes;
     }
 
@@ -160 +158 @@
     /// Get a function node's child indices from left to right
     /// </summary>
-    /// <typeparam name="T"></typeparam>
-    /// <param name="nodes"></param>
-    /// <param name="i"></param>
+    /// <typeparam name="T">The data type encapsulated by a hash node</typeparam>
+    /// <param name="nodes">An array of hash nodes with up-to-date node sizes</param>
+    /// <param name="i">The index in the array of hash nodes of the node whose children we want to iterate</param>
     /// <returns>An array containing child indices</returns>
     public static int[] IterateChildren<T>(this HashNode<T>[] nodes, int i) where T : class {
@@ -177 +175 @@
     }
 
-    public static void UpdateNodeSizes<T>(this HashNode<T>[] nodes) where T : class {
+    public static HashNode<T>[] UpdateNodeSizes<T>(this HashNode<T>[] nodes) where T : class {
       for (int i = 0; i < nodes.Length; ++i) {
         var node = nodes[i];
@@ -189 +187 @@
         }
       }
+      return nodes;
     }
 
@@ -219 +218 @@
 
     public static HashNode<T>[] Reduce<T>(this HashNode<T>[] nodes) where T : class {
-      nodes.UpdateNodeSizes();
       int i = nodes.Length - 1;
       foreach (int c in nodes.IterateChildren(i)) {
@@ -237 +235 @@
         if (node.Enabled) { reduced[i++] = node; }
       }
-      reduced.UpdateNodeSizes();
-      return reduced;
+      return reduced.UpdateNodeSizes();
     }
   }

trunk/HeuristicLab.Problems.DataAnalysis.Symbolic/3.4/Hashing/SymbolicExpressionTreeHash.cs

@@ -22 +22 @@
     }
 
+    // compute node hashes without sorting the arguments
     public static Dictionary<ISymbolicExpressionTreeNode, int> ComputeNodeHashes(this ISymbolicExpressionTree tree) {
       var root = tree.Root.GetSubtree(0).GetSubtree(0);
@@ -80 +81 @@
 
     public static HashNode<ISymbolicExpressionTreeNode>[] MakeNodes(this ISymbolicExpressionTreeNode node) {
-      return node.IterateNodesPostfix().Select(ToHashNode).ToArray();
+      return node.IterateNodesPostfix().Select(ToHashNode).ToArray().UpdateNodeSizes();
     }