Exemplo n.º 1
0
bool MinDist::train(LabelledClassificationData &labelledTrainingData,double gamma){
    
    const unsigned int M = labelledTrainingData.getNumSamples();
    const unsigned int N = labelledTrainingData.getNumDimensions();
    const unsigned int K = labelledTrainingData.getNumClasses();
    trained = false;
    models.clear();
    classLabels.clear();
    
    if( M == 0 ){
        errorLog << "train(LabelledClassificationData &labelledTrainingData,double gamma) - Training data has zero samples!" << endl;
        return false;
    }
    
    if( M <= numClusters ){
        errorLog << "train(LabelledClassificationData &labelledTrainingData,double gamma) - There are not enough training samples for the number of clusters. Either reduce the number of clusters or increase the number of training samples!" << endl;
        return false;
    }

    numFeatures = N;
    numClasses = K;
    models.resize(K);
    classLabels.resize(K);
    ranges = labelledTrainingData.getRanges();
    
    //Train each of the models
	for(UINT k=0; k<numClasses; k++){
        
        //Get the class label for the kth class
        UINT classLabel = labelledTrainingData.getClassTracker()[k].classLabel;
        
        //Set the kth class label
        classLabels[k] = classLabel;
        
        //Get all the training data for this class
        LabelledClassificationData classData = labelledTrainingData.getClassData(classLabel);
        MatrixDouble data(classData.getNumSamples(),N);
        
        //Copy the training data into a matrix, scaling the training data if needed
        for(UINT i=0; i<data.getNumRows(); i++){
            for(UINT j=0; j<data.getNumCols(); j++){
                if( useScaling ){
                    data[i][j] = scale(classData[i][j],ranges[j].minValue,ranges[j].maxValue,0,1);
                }else data[i][j] = classData[i][j];
            }
        }
        
        //Train the model for this class
		models[k].setGamma( gamma );
		if( !models[k].train(classLabel,data,numClusters) ){
            errorLog << "train(LabelledClassificationData &labelledTrainingData,double gamma) - Failed to train model for class: " << classLabel;
            errorLog << ". This is might be because this class does not have enough training samples! You should reduce the number of clusters or increase the number of training samples for this class." << endl;
            models.clear();
            return false;
        }
        
	}
    
    trained = true;
    return true;
}
Exemplo n.º 2
0
bool ANBC::train(LabelledClassificationData &labelledTrainingData,double gamma) {

    const unsigned int M = labelledTrainingData.getNumSamples();
    const unsigned int N = labelledTrainingData.getNumDimensions();
    const unsigned int K = labelledTrainingData.getNumClasses();
    trained = false;
    models.clear();
    classLabels.clear();

    if( M == 0 ) {
        errorLog << "train(LabelledClassificationData &labelledTrainingData,double gamma) - Training data has zero samples!" << endl;
        return false;
    }

    if( weightsDataSet ) {
        if( weightsData.getNumDimensions() != N ) {
            errorLog << "train(LabelledClassificationData &labelledTrainingData,double gamma) - The number of dimensions in the weights data (" << weightsData.getNumDimensions() << ") is not equal to the number of dimensions of the training data (" << N << ")" << endl;
            return false;
        }
    }

    numFeatures = N;
    numClasses = K;
    models.resize(K);
    classLabels.resize(K);
    ranges = labelledTrainingData.getRanges();

    //Train each of the models
    for(UINT k=0; k<numClasses; k++) {

        //Get the class label for the kth class
        UINT classLabel = labelledTrainingData.getClassTracker()[k].classLabel;

        //Set the kth class label
        classLabels[k] = classLabel;

        //Get the weights for this class
        VectorDouble weights(numFeatures);
        if( weightsDataSet ) {
            bool weightsFound = false;
            for(UINT i=0; i<weightsData.getNumSamples(); i++) {
                if( weightsData[i].getClassLabel() == classLabel ) {
                    weights = weightsData[i].getSample();
                    weightsFound = true;
                    break;
                }
            }

            if( !weightsFound ) {
                errorLog << "train(LabelledClassificationData &labelledTrainingData,double gamma) - Failed to find the weights for class " << classLabel << endl;
                return false;
            }
        } else {
            //If the weights data has not been set then all the weights are 1
            for(UINT j=0; j<numFeatures; j++) weights[j] = 1.0;
        }

        //Get all the training data for this class
        LabelledClassificationData classData = labelledTrainingData.getClassData(classLabel);
        MatrixDouble data(classData.getNumSamples(),N);

        //Copy the training data into a matrix, scaling the training data if needed
        for(UINT i=0; i<data.getNumRows(); i++) {
            for(UINT j=0; j<data.getNumCols(); j++) {
                if( useScaling ) {
                    data[i][j] = scale(classData[i][j],ranges[j].minValue,ranges[j].maxValue,MIN_SCALE_VALUE,MAX_SCALE_VALUE);
                } else data[i][j] = classData[i][j];
            }
        }

        //Train the model for this class
        models[k].gamma = gamma;
        if( !models[k].train(classLabel,data,weights) ) {
            errorLog << "train(LabelledClassificationData &labelledTrainingData,double gamma) - Failed to train model for class: " << classLabel << endl;

            //Try and work out why the training failed
            if( models[k].N == 0 ) {
                errorLog << "train(LabelledClassificationData &labelledTrainingData,double gamma) - N == 0!" << endl;
                models.clear();
                return false;
            }
            for(UINT j=0; j<numFeatures; j++) {
                if( models[k].mu[j] == 0 ) {
                    errorLog << "train(LabelledClassificationData &labelledTrainingData,double gamma) - The mean of column " << j+1 << " is zero! Check the training data" << endl;
                    models.clear();
                    return false;
                }
            }
            models.clear();
            return false;
        }

    }

    //Store the null rejection thresholds
    nullRejectionThresholds.resize(numClasses);
    for(UINT k=0; k<numClasses; k++) {
        nullRejectionThresholds[k] = models[k].threshold;
    }

    //Flag that the models have been trained
    trained = true;
    return trained;

}
Exemplo n.º 3
0
bool GMM::train(LabelledClassificationData trainingData){
    
    //Clear any old models
    models.clear();
    trained = false;
    numFeatures = 0;
    numClasses = 0;
    
    if( trainingData.getNumSamples() == 0 ){
        errorLog << "train(LabelledClassificationData &trainingData) - Training data is empty!" << endl;
        return false;
    }
    
    //Set the number of features and number of classes and resize the models buffer
    numFeatures = trainingData.getNumDimensions();
    numClasses = trainingData.getNumClasses();
    models.resize(numClasses);
    
    if( numFeatures >= 6 ){
        warningLog << "train(LabelledClassificationData &trainingData) - The number of features in your training data is high (" << numFeatures << ").  The GMMClassifier does not work well with high dimensional data, you might get better results from one of the other classifiers." << endl;
    }
    
    //Get the ranges of the training data if the training data is going to be scaled
    if( useScaling ){
        ranges = trainingData.getRanges();
    }

    //Fit a Mixture Model to each class (independently)
    for(UINT k=0; k<numClasses; k++){
        UINT classLabel = trainingData.getClassTracker()[k].classLabel;
        LabelledClassificationData classData = trainingData.getClassData( classLabel );
        
        //Scale the training data if needed
        if( useScaling ){
            if( !classData.scale(ranges,GMM_MIN_SCALE_VALUE, GMM_MAX_SCALE_VALUE) ){
                errorLog << "train(LabelledClassificationData &trainingData) - Failed to scale training data!" << endl;
                return false;

            }
        }
        
        //Convert the labelled data to unlabelled data
        UnlabelledClassificationData unlabelledData = classData.reformatAsUnlabelledClassificationData();
        
        //Train the Mixture Model for this class
        GaussianMixtureModels gaussianMixtureModel;
        gaussianMixtureModel.setMinChange( minChange );
        gaussianMixtureModel.setMaxIter( maxIter );
        if( !gaussianMixtureModel.train(unlabelledData, numMixtureModels) ){
            errorLog << "train(LabelledClassificationData &trainingData) - Failed to train Mixture Model for class " << classLabel << endl;
            return false;
        }
        
        //Setup the model container
        models[k].resize( numMixtureModels );
        models[k].setClassLabel( classLabel );
        
        //Store the mixture model in the container
        for(UINT j=0; j<numMixtureModels; j++){
            models[k][j].mu = gaussianMixtureModel.getMu().getRowVector(j);
            models[k][j].sigma = gaussianMixtureModel.getSigma()[j];
            
            //Compute the determinant and invSigma for the realtime prediction
            LUDecomposition ludcmp(models[k][j].sigma);
            if( !ludcmp.inverse( models[k][j].invSigma ) ){
                models.clear();
                errorLog << "train(LabelledClassificationData &trainingData) - Failed to invert Matrix for class " << classLabel << "!" << endl;
                return false;
            }
            models[k][j].det = ludcmp.det();
        }
        
        //Compute the normalize factor
        models[k].recomputeNormalizationFactor();
        
        //Compute the rejection thresholds
        double mu = 0;
        double sigma = 0;
        VectorDouble predictionResults(classData.getNumSamples(),0);
        for(UINT i=0; i<classData.getNumSamples(); i++){
            vector< double > sample = classData[i].getSample();
            predictionResults[i] = models[k].computeMixtureLikelihood( sample );
            mu += predictionResults[i];
        }
        
        //Update mu
        mu /= double( classData.getNumSamples() );
        
        //Calculate the standard deviation
        for(UINT i=0; i<classData.getNumSamples(); i++) 
            sigma += SQR( (predictionResults[i]-mu) );
        sigma = sqrt( sigma / (double(classData.getNumSamples())-1.0) );
        sigma = 0.2;
        
        //Set the models training mu and sigma 
        models[k].setTrainingMuAndSigma(mu,sigma);
        
        if( !models[k].recomputeNullRejectionThreshold(nullRejectionCoeff) && useNullRejection ){
            warningLog << "train(LabelledClassificationData &trainingData) - Failed to recompute rejection threshold for class " << classLabel << " - the nullRjectionCoeff value is too high!" << endl;
        }
        
        //cout << "Training Mu: " << mu << " TrainingSigma: " << sigma << " RejectionThreshold: " << models[k].getNullRejectionThreshold() << endl;
        //models[k].printModelValues();
    }
    
    //Reset the class labels
    classLabels.resize(numClasses);
    for(UINT k=0; k<numClasses; k++){
        classLabels[k] = models[k].getClassLabel();
    }
    
    //Resize the rejection thresholds
    nullRejectionThresholds.resize(numClasses);
    for(UINT k=0; k<numClasses; k++){
        nullRejectionThresholds[k] = models[k].getNullRejectionThreshold();
    }
    
    //Flag that the models have been trained
    trained = true;
    
    return true;
}