1 files changed, 36 insertions, 5 deletions
diff --git a/src/jcgp/backend/population/Node.java b/src/jcgp/backend/population/Node.java
index 3bcf3da..7712c50 100644
--- a/src/jcgp/backend/population/Node.java
+++ b/src/jcgp/backend/population/Node.java
@@ -3,6 +3,7 @@ package jcgp.backend.population;
 import java.util.ArrayList;
 
 import jcgp.backend.function.Function;
+import jcgp.backend.resources.Resources;
 
 /**
  * Nodes make up the main part of the chromosome, 
@@ -16,6 +17,10 @@ import jcgp.backend.function.Function;
  * (determined by the maximum arity of the function set)
  * and must be reinstantiated if the experiment arity
  * changes.
+ * <br><br>
+ * When mutating a node, it is easiest to use {@code mutate()}.
+ * Alternatively, you may also perform a specific mutation using
+ * {@code setConnection(...)} and {@code setFunction(...)}.
  * 
  * @author Eduardo Pedroni
  *
@@ -122,6 +127,24 @@ public class Node implements Mutable, Connection {
 			}
 		}
 	}
+	
+	/**
+	 * This method sets the indexed connection to the specified new connection.
+	 * If the given connection is null or disrespects levels back, it is discarded
+	 * and no connections are changed.
+	 * 
+	 * @param index the connection index to set.
+	 * @param newConnection the {@code Connection} to connect to.
+	 */
+	public void setConnection(int index, Connection newConnection) {
+		// connection must not be null
+		if (newConnection != null) {
+			//if () {
+				connections[index] = newConnection;
+			chromosome.recomputeActiveNodes();
+			//}
+		}
+	}
 
 	@Override
 	public boolean copyOf(Mutable element) {
@@ -174,11 +197,19 @@ public class Node implements Mutable, Connection {
 	}
 
 	@Override
-	public void setConnection(int index, Connection newConnection) {
-		// connection must not be null
-		if (newConnection != null) {
-			connections[index] = newConnection;
-			chromosome.recomputeActiveNodes();
+	public void mutate() {
+		Resources resources = chromosome.getResources();
+		
+		// choose to mutate the function or a connection
+		int geneType = resources.getRandomInt(1 + resources.arity());
+		
+		// if the int is less than 1, mutate function, else mutate connections 
+		if (geneType < 1) {			
+			setFunction(resources.getRandomFunction());
+		} else {
+			// if we decided to mutate connection, subtract 1 from geneType so it fits into the arity range
+			geneType--;
+			setConnection(geneType, chromosome.getRandomConnection(column));
 		}
 	}