Integral distance metric

src/eva2/server/go/operators/distancemetric/DoubleIntegralMetric.java

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+package eva2.server.go.operators.distancemetric;
+
+import java.io.Serializable;
+
+import eva2.server.go.individuals.AbstractEAIndividual;
+import eva2.server.go.strategies.ParticleSwarmOptimization;
+import eva2.tools.EVAERROR;
+import eva2.tools.math.Mathematics;
+
+/**
+ * Calculate the euclidean difference between discrete integrals, which is 
+ * 	d(x,y)=sqrt(sum_i=1^n(((sum_j=1^i(x_j))-(sum_j=1^i(y_j)))^2)).
+ * 
+ * This can be used with any individual type that implements getDoublePositionShallow.
+ * 
+ * @see AbstractEAIndividual.getDoublePositionShallow(AbstractEAIndividual)
+ * 
+ * @author mkron
+ *
+ */
+public class DoubleIntegralMetric implements InterfaceDistanceMetric, Serializable {
+	boolean oneNormed=true; // if true, the vectors are normed to unity sum before comparison.
+//	String indyDataKey=null;
+	
+	public DoubleIntegralMetric() {}
+	
+	public DoubleIntegralMetric(boolean normed) {
+		oneNormed=normed;
+	}
+	
+    public Object clone() {
+    	return new DoubleIntegralMetric(oneNormed);
+    }
+
+    public double distance(AbstractEAIndividual indy1, AbstractEAIndividual indy2) {
+		double[]    dIndy1=null, dIndy2=null;
+//		String indyDataKey = ParticleSwarmOptimization.partBestPosKey;
+//		if (indyDataKey!=null && (indyDataKey.length()>0)) {
+//			try {
+//				dIndy1 = (double[]) indy1.getData(indyDataKey);
+//				dIndy2 = (double[]) indy2.getData(indyDataKey);
+//			} catch (Exception e) {dIndy1=null;}
+//		} else dIndy1=null;
+		
+		if (dIndy1==null|| dIndy2==null) {
+			dIndy1 = AbstractEAIndividual.getDoublePositionShallow(indy1);
+			dIndy2 = AbstractEAIndividual.getDoublePositionShallow(indy2);
+		}
+
+		if (oneNormed) {
+			double l1 = Mathematics.sum(dIndy1);
+			double l2 = Mathematics.sum(dIndy2);
+			if (l1!=1. || l2!=1.) { // norming really necessary
+				if (l1==0 || l2==0) EVAERROR.errorMsgOnce("Warning, double vector with zero sum will yield infinite distances in " + this.getClass());
+				dIndy1 = Mathematics.svDiv(l1, dIndy1);
+				dIndy2 = Mathematics.svDiv(l2, dIndy2);
+			}
+		}
+		
+		double sum1=0, sum2=0;
+		double tmpDiff=0, sqrDiffSum=0;
+//		System.out.println(Mathematics.sum(dIndy1));
+//		System.out.println(Mathematics.sum(dIndy2));
+		for (int i = 0; (i < dIndy1.length) && (i < dIndy2.length); i++) {
+			sum1+=dIndy1[i];
+			sum2+=dIndy2[i];
+			tmpDiff=(sum1-sum2);
+			sqrDiffSum+=(tmpDiff*tmpDiff);
+		}
+		return Math.sqrt(sqrDiffSum);
+    }
+
+    public String getName() {
+    	return "Real-valued integral metric";
+    }
+    
+    public static String globalInfo() {
+    	return "A simple integral metric for real-valued types.";
+    }
+    
+    public boolean isOneNormed() {
+		return oneNormed;
+	}
+	public void setOneNormed(boolean normedByLength) {
+		this.oneNormed = normedByLength;
+	}
+	public String oneNormedTipText() {
+		return "If true, both vectors are normed to unity sum before comparison.";
+	}
+    
+}