Java MatrixOps.rowPlusEquals方法代码示例

import cc.mallet.types.MatrixOps; //导入方法依赖的package包/类
public double getValue ()
	{
		if (cachedValueStale) {
			numGetValueCalls++;
			cachedValue = 0;
			// We'll store the expectation values in "cachedGradient" for now
			cachedGradientStale = true;
			MatrixOps.setAll (cachedGradient, 0.0);
			// Incorporate likelihood of data
			double[] scores = new double[trainingList.getTargetAlphabet().size()];
			double value = 0.0;
			Iterator<Instance> iter = trainingList.iterator();
			int ii=0;
			while (iter.hasNext()) {
				ii++;
				Instance instance = iter.next();
				double instanceWeight = trainingList.getInstanceWeight(instance);
				Labeling labeling = instance.getLabeling ();
				if (labeling == null)
					continue;
				//System.out.println("L Now "+inputAlphabet.size()+" regular features.");

				this.theClassifier.getClassificationScores (instance, scores);
				FeatureVector fv = (FeatureVector) instance.getData ();
				int li = labeling.getBestIndex();
				value = - (instanceWeight * Math.log (scores[li]));
				if(Double.isNaN(value)) {
					logger.fine ("MaxEntTrainer: Instance " + instance.getName() +
							"has NaN value. log(scores)= " + Math.log(scores[li]) +
							" scores = " + scores[li] + 
							" has instance weight = " + instanceWeight);

				}
				if (Double.isInfinite(value)) {
					logger.warning ("Instance "+instance.getSource() + " has infinite value; skipping value and gradient");
					cachedValue -= value;
					cachedValueStale = false;
					return -value;
//					continue;
				}
				cachedValue += value;
				for (int si = 0; si < scores.length; si++) {
					if (scores[si] == 0) continue;
					assert (!Double.isInfinite(scores[si]));
					MatrixOps.rowPlusEquals (cachedGradient, numFeatures,
							si, fv, -instanceWeight * scores[si]);
					cachedGradient[numFeatures*si + defaultFeatureIndex] += (-instanceWeight * scores[si]);
				}
			}
			//logger.info ("-Expectations:"); cachedGradient.print();

			// Incorporate prior on parameters
			double prior = 0;
			if (usingHyperbolicPrior) {
				for (int li = 0; li < numLabels; li++)
					for (int fi = 0; fi < numFeatures; fi++)
						prior += (hyperbolicPriorSlope / hyperbolicPriorSharpness
								* Math.log (Maths.cosh (hyperbolicPriorSharpness * parameters[li *numFeatures + fi])));
			}
			else if (usingGaussianPrior) {
				for (int li = 0; li < numLabels; li++)
					for (int fi = 0; fi < numFeatures; fi++) {
						double param = parameters[li*numFeatures + fi];
						prior += param * param / (2 * gaussianPriorVariance);
					}
			}

			double oValue = cachedValue;
			cachedValue += prior;
			cachedValue *= -1.0; // MAXIMIZE, NOT MINIMIZE
			cachedValueStale = false;
			progressLogger.info ("Value (labelProb="+oValue+" prior="+prior+") loglikelihood = "+cachedValue);
		}
		return cachedValue;
	}