add optimization library source code

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

1 files changed, 41 insertions, 0 deletions

diff --git a/gi/posterior-regularisation/prjava/src/optimization/stopCriteria/ValueDifference.java b/gi/posterior-regularisation/prjava/src/optimization/stopCriteria/ValueDifference.java
new file mode 100644
index 00000000..e5d07229
--- /dev/null
+++ b/gi/posterior-regularisation/prjava/src/optimization/stopCriteria/ValueDifference.java
@@ -0,0 +1,41 @@
+package optimization.stopCriteria;
+
+import optimization.gradientBasedMethods.Objective;
+import optimization.util.MathUtils;
+
+public class ValueDifference 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 ValueDifference(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 - currentValue   < valueConvergenceValue){
+//				System.out.println("Leaving different in values is to small: Prev " 
+//						+ previousValue + " Curr: " + currentValue 
+//						+ " diff: " + (previousValue - currentValue));
+				return true;
+			}
+			return false;
+		}
+		
+	}
+}