add optimization library source code

git-svn-id: https://ws10smt.googlecode.com/svn/trunk@204 ec762483-ff6d-05da-a07a-a48fb63a330f

1 files changed, 54 insertions, 0 deletions

diff --git a/gi/posterior-regularisation/prjava/src/optimization/stopCriteria/NormalizedValueDifference.java b/gi/posterior-regularisation/prjava/src/optimization/stopCriteria/NormalizedValueDifference.java
new file mode 100644
index 00000000..6dbbc50d
--- /dev/null
+++ b/gi/posterior-regularisation/prjava/src/optimization/stopCriteria/NormalizedValueDifference.java
@@ -0,0 +1,54 @@
+package optimization.stopCriteria;
+
+import optimization.gradientBasedMethods.Objective;
+import optimization.util.MathUtils;
+
+public class NormalizedValueDifference implements StopingCriteria{
+	
+	/**
+	 * Stop if the different between values is smaller than a treshold
+	 */
+	protected double valueConvergenceValue=0.01;
+	protected double previousValue = Double.NaN;
+	protected double currentValue = Double.NaN;
+	
+	public NormalizedValueDifference(double valueConvergenceValue){
+		this.valueConvergenceValue = valueConvergenceValue;
+	}
+	
+	public void reset(){
+		previousValue = Double.NaN;
+		currentValue = Double.NaN;
+	}
+
+	
+	public boolean stopOptimization(Objective obj){
+		if(Double.isNaN(currentValue)){
+			currentValue = obj.getValue();
+			return false;
+		}else {
+			previousValue = currentValue;
+			currentValue = obj.getValue();
+			if(previousValue != 0){
+				double valueDiff = Math.abs(previousValue - currentValue)/Math.abs(previousValue);
+				if( valueDiff  < valueConvergenceValue){
+					System.out.println("Leaving different in values is to small: Prev " 
+							+ (previousValue/previousValue) + " Curr: " + (currentValue/previousValue) 
+							+ " diff: " + valueDiff);
+					return true;
+				}
+			}else{
+				double valueDiff = Math.abs(previousValue - currentValue);
+				if( valueDiff  < valueConvergenceValue){
+					System.out.println("Leaving different in values is to small: Prev " 
+							+ (previousValue) + " Curr: " + (currentValue) 
+							+ " diff: " + valueDiff);
+					return true;
+				}
+			}
+
+			return false;
+		}
+		
+	}
+}