Refactored the resources mechanics, implemented a few of the chromosome tests

1 files changed, 169 insertions, 0 deletions

diff --git a/src/jcgp/Utilities.java b/src/jcgp/Utilities.java
new file mode 100644
index 0000000..7de701a
--- /dev/null
+++ b/src/jcgp/Utilities.java
@@ -0,0 +1,169 @@
+package jcgp;
+
+import java.util.Random;
+
+import jcgp.function.Function;
+import jcgp.function.FunctionSet;
+import jcgp.population.*;
+
+public class Utilities {
+	
+	private static Random numberGenerator;
+	private static FunctionSet functionSet;
+	
+	public static void setResources(Random numberGenerator, FunctionSet functionSet) {
+		Utilities.numberGenerator = numberGenerator;
+		Utilities.functionSet = functionSet;
+	}
+
+	public static int getRandomInt(int limit){
+		return numberGenerator.nextInt(limit);
+	}
+
+	public static double getRandomDouble(int limit){
+		return numberGenerator.nextDouble() * limit;
+	}
+
+	/**
+	 * Returns a random allowed connection respecting levels back.
+	 * This method may always pick inputs, as they can be picked
+	 * regardless of the column.
+	 * 
+	 * @param chromosome the chromosome to pick from
+	 * @param column the column to use as reference
+	 * @return a random connection
+	 */
+	public static Connection getRandomConnection(Chromosome chromosome, int column){
+		// work out the allowed range obeying levels back
+		int allowedColumns = ((column >= Parameters.getLevelsBack()) ? Parameters.getLevelsBack() : column);
+		int offset = column - allowedColumns;
+
+		// choose input or node
+		int connectionType = getRandomInt(Parameters.getInputs() + (Parameters.getRows() * allowedColumns));
+		if (connectionType < Parameters.getInputs()) {
+			// input
+			return chromosome.getInput(getRandomInt(Parameters.getInputs()));
+		} else {
+			// node				
+			return chromosome.getNode(getRandomInt(Parameters.getRows()), getRandomInt(allowedColumns) + offset);
+		}
+	}
+
+	/**
+	 * Returns a random allowed connection. 
+	 * 
+	 * This method may always pick inputs, as they can be picked
+	 * regardless of the column.
+	 * 
+	 * @param chromosome the chromosome to pick from
+	 * @param column the column to use as reference
+	 * @param levelsBack whether or not to respect levels back
+	 * @return a random connection
+	 */
+	public static Connection getRandomConnection(Chromosome chromosome, int column, boolean levelsBack){
+		if (levelsBack) {
+			return getRandomConnection(chromosome, column);
+		} else {
+			// choose input or node
+			int connectionType = getRandomInt(Parameters.getInputs() + (Parameters.getRows() * column));
+			if (connectionType < Parameters.getInputs()) {
+				// input
+				return chromosome.getInput(getRandomInt(Parameters.getInputs()));
+			} else {
+				// node				
+				return chromosome.getNode(getRandomInt(Parameters.getRows()), getRandomInt(column));
+			}
+		}
+	}
+
+	/**
+	 * @param chromosome the chromosome to choose from
+	 * @return a random input
+	 */
+	public static Input getRandomInput(Chromosome chromosome){
+		return chromosome.getInput(getRandomInt(Parameters.getInputs()));
+	}
+
+	/**
+	 * Returns a random allowed node respecting levels back.
+	 * 
+	 * This method will NOT pick inputs.
+	 * 
+	 * @param chromosome the chromosome to pick from
+	 * @param column the column to use as reference
+	 * @return a random node
+	 */
+	public static Node getRandomNode(Chromosome chromosome, int column){
+		// work out the allowed range obeying levels back
+		int allowedColumns = ((column >= Parameters.getLevelsBack()) ? Parameters.getLevelsBack() : column);
+		int offset = column - allowedColumns;
+
+		// pick a random allowed column and row
+		int randomColumn = (getRandomInt(allowedColumns) + offset);
+		int randomRow = (getRandomInt(Parameters.getRows()));
+
+		return chromosome.getNode(randomRow, randomColumn);
+	}
+
+	/**
+	 * Returns a random allowed node.
+	 * 
+	 * This method will NOT pick inputs.
+	 * 
+	 * @param chromosome the chromosome to pick from
+	 * @param column the column to use as reference
+	 * @param levelsBack whether or not to respect levels back
+	 * @return a random node
+	 */
+	public static Node getRandomNode(Chromosome chromosome, int column, boolean levelsBack){
+		if (levelsBack) {
+			return getRandomNode(chromosome, column);
+		} else {
+			// pick any random column before the given column
+			int randomColumn = (getRandomInt(column));
+			// pick a random rowgetColumns
+			int randomRow = (getRandomInt(Parameters.getRows()));
+			return chromosome.getNode(randomRow, randomColumn);
+		}
+	}
+
+	/**
+	 * This method picks a random mutable element from the given chromosome.
+	 * 
+	 * It will pick outputs or nodes fairly.
+	 * 
+	 * @param chromosome the chromosome to pick from
+	 * @return a random mutable element
+	 */
+	public static MutableElement getRandomMutable(Chromosome chromosome){
+		// choose output or node
+		int connectionType = getRandomInt(Parameters.getOutputs() + Parameters.getNodeCount());
+
+		if (connectionType < Parameters.getOutputs()) {
+			// outputs
+			return chromosome.getOutput(getRandomInt(Parameters.getOutputs()));
+		} else {
+			// node				
+			return chromosome.getNode(getRandomInt(Parameters.getRows()), getRandomInt(Parameters.getRows()));
+		}
+	}		
+
+	/**
+	 * pick from any column - use this for setting outputs
+	 * 
+	 * @param chromosome
+	 * @return
+	 */
+	public static Node getRandomNode(Chromosome chromosome) {
+		return chromosome.getNode(getRandomInt(Parameters.getRows()), getRandomInt(Parameters.getColumns()));
+	}
+
+	public static Function getRandomFunction() {
+		return functionSet.getFunction(Utilities.getRandomInt(functionSet.getFunctionCount()));
+	}
+
+	public static Function getFunction(int index) {
+		return functionSet.getFunction(index);
+	}
+
+}