/// <summary>Solves the problem using OWLQN.</summary>
/// <remarks>
/// Solves the problem using OWLQN. The solution
/// is stored in the
/// <c>lambda</c>
/// array of
/// <c>prob</c>
/// . Note that the
/// likelihood function will be a penalized L2 likelihood function unless you
/// have turned this off via setting the priorSigmaS to 0.0.
/// </remarks>
/// <param name="weight">
/// Controls the sparseness/regularization of the L1 solution.
/// The bigger the number the sparser the solution. Weights between
/// 0.01 and 1.0 typically give good performance.
/// </param>
public virtual void SolveL1(double weight)
{
CGRunner.LikelihoodFunction df = new CGRunner.LikelihoodFunction(prob, tol, useGaussianPrior, priorSigmaS, sigmaSquareds);
IMinimizer <IDiffFunction> owl = ReflectionLoading.LoadByReflection("edu.stanford.nlp.optimization.OWLQNMinimizer", weight);
prob.lambda = owl.Minimize(df, tol, new double[df.DomainDimension()]);
PrintOptimizationResults(df, null);
}
private double[] TrainWeightsUsingNonLinearCRF(AbstractCachingDiffFunction func, IEvaluator[] evaluators)
{
IMinimizer <IDiffFunction> minimizer = GetMinimizer(0, evaluators);
double[] initialWeights;
if (flags.initialWeights == null)
{
initialWeights = func.Initial();
}
else
{
log.Info("Reading initial weights from file " + flags.initialWeights);
try
{
using (DataInputStream dis = new DataInputStream(new BufferedInputStream(new GZIPInputStream(new FileInputStream(flags.initialWeights)))))
{
initialWeights = ConvertByteArray.ReadDoubleArr(dis);
}
}
catch (IOException)
{
throw new Exception("Could not read from double initial weight file " + flags.initialWeights);
}
}
log.Info("numWeights: " + initialWeights.Length);
if (flags.testObjFunction)
{
StochasticDiffFunctionTester tester = new StochasticDiffFunctionTester(func);
if (tester.TestSumOfBatches(initialWeights, 1e-4))
{
log.Info("Testing complete... exiting");
System.Environment.Exit(1);
}
else
{
log.Info("Testing failed....exiting");
System.Environment.Exit(1);
}
}
//check gradient
if (flags.checkGradient)
{
if (func.GradientCheck())
{
log.Info("gradient check passed");
}
else
{
throw new Exception("gradient check failed");
}
}
return(minimizer.Minimize(func, flags.tolerance, initialWeights));
}
/// <summary>
/// <inheritDoc/>
///
/// </summary>
public virtual double[] Minimize(IDiffFunction function, double functionTolerance, double[] initial, int maxIterations)
{
double[] x = firstMinimizer.Minimize(function, functionTolerance, initial, iterationCutoff);
return(secondMinimizer.Minimize(function, functionTolerance, x, maxIterations));
}
protected internal override double[] TrainWeights(int[][][][] data, int[][] labels, IEvaluator[] evaluators, int pruneFeatureItr, double[][][][] featureVals)
{
int numFeatures = featureIndex.Size();
int numLopExpert = flags.numLopExpert;
double[][] lopExpertWeights = new double[numLopExpert][];
GetFeatureBoundaryIndices(numFeatures, numLopExpert);
if (flags.initialLopWeights != null)
{
try
{
using (BufferedReader br = IOUtils.ReaderFromString(flags.initialLopWeights))
{
log.Info("Reading initial LOP weights from file " + flags.initialLopWeights + " ...");
IList <double[]> listOfWeights = new List <double[]>(numLopExpert);
for (string line; (line = br.ReadLine()) != null;)
{
line = line.Trim();
string[] parts = line.Split("\t");
double[] wArr = new double[parts.Length];
for (int i = 0; i < parts.Length; i++)
{
wArr[i] = double.ParseDouble(parts[i]);
}
listOfWeights.Add(wArr);
}
System.Diagnostics.Debug.Assert((listOfWeights.Count == numLopExpert));
log.Info("Done!");
for (int i_1 = 0; i_1 < numLopExpert; i_1++)
{
lopExpertWeights[i_1] = listOfWeights[i_1];
}
}
}
catch (IOException)
{
// DataInputStream dis = new DataInputStream(new BufferedInputStream(new GZIPInputStream(new FileInputStream(
// flags.initialLopWeights))));
// initialScales = Convert.readDoubleArr(dis);
throw new Exception("Could not read from double initial LOP weights file " + flags.initialLopWeights);
}
}
else
{
for (int lopIter = 0; lopIter < numLopExpert; lopIter++)
{
int[][][][] partialData = CreatePartialDataForLOP(lopIter, data);
if (flags.randomLopWeights)
{
lopExpertWeights[lopIter] = base.GetObjectiveFunction(partialData, labels).Initial();
}
else
{
lopExpertWeights[lopIter] = base.TrainWeights(partialData, labels, evaluators, pruneFeatureItr, null);
}
}
if (flags.includeFullCRFInLOP)
{
double[][] newLopExpertWeights = new double[numLopExpert + 1][];
System.Array.Copy(lopExpertWeights, 0, newLopExpertWeights, 0, lopExpertWeights.Length);
if (flags.randomLopWeights)
{
newLopExpertWeights[numLopExpert] = base.GetObjectiveFunction(data, labels).Initial();
}
else
{
newLopExpertWeights[numLopExpert] = base.TrainWeights(data, labels, evaluators, pruneFeatureItr, null);
}
ICollection <int> newSet = Generics.NewHashSet(numFeatures);
IList <int> newList = new List <int>(numFeatures);
for (int fIndex = 0; fIndex < numFeatures; fIndex++)
{
newSet.Add(fIndex);
newList.Add(fIndex);
}
featureIndicesSetArray.Add(newSet);
featureIndicesListArray.Add(newList);
numLopExpert += 1;
lopExpertWeights = newLopExpertWeights;
}
}
// Dumb scales
// double[] lopScales = new double[numLopExpert];
// Arrays.fill(lopScales, 1.0);
CRFLogConditionalObjectiveFunctionForLOP func = new CRFLogConditionalObjectiveFunctionForLOP(data, labels, lopExpertWeights, windowSize, classIndex, labelIndices, map, flags.backgroundSymbol, numLopExpert, featureIndicesSetArray, featureIndicesListArray
, flags.backpropLopTraining);
cliquePotentialFunctionHelper = func;
IMinimizer <IDiffFunction> minimizer = GetMinimizer(0, evaluators);
double[] initialScales;
//TODO(mengqiu) clean this part up when backpropLogTraining == true
if (flags.initialLopScales == null)
{
initialScales = func.Initial();
}
else
{
log.Info("Reading initial LOP scales from file " + flags.initialLopScales);
try
{
using (DataInputStream dis = new DataInputStream(new BufferedInputStream(new GZIPInputStream(new FileInputStream(flags.initialLopScales)))))
{
initialScales = ConvertByteArray.ReadDoubleArr(dis);
}
}
catch (IOException)
{
throw new Exception("Could not read from double initial LOP scales file " + flags.initialLopScales);
}
}
double[] learnedParams = minimizer.Minimize(func, flags.tolerance, initialScales);
double[] rawScales = func.SeparateLopScales(learnedParams);
double[] lopScales = ArrayMath.Softmax(rawScales);
log.Info("After SoftMax Transformation, learned scales are:");
for (int lopIter_1 = 0; lopIter_1 < numLopExpert; lopIter_1++)
{
log.Info("lopScales[" + lopIter_1 + "] = " + lopScales[lopIter_1]);
}
double[][] learnedLopExpertWeights = lopExpertWeights;
if (flags.backpropLopTraining)
{
learnedLopExpertWeights = func.SeparateLopExpertWeights(learnedParams);
}
return(CRFLogConditionalObjectiveFunctionForLOP.CombineAndScaleLopWeights(numLopExpert, learnedLopExpertWeights, lopScales));
}