Examples with Coefficients org.dmg.pmml.CoefficientsDocument.Coefficients used on opensource projects

Example 1 with Coefficients

use of org.dmg.pmml.CoefficientsDocument.Coefficients in project knime-core by knime.

the class PMMLSVMTranslator method addSVMs.

/**
 * @param svmModel the SVM model to add the SVMs to
 */
private void addSVMs(final SupportVectorMachineModel svmModel) {
    if (m_svms.size() == 0) {
        svmModel.addNewSupportVectorMachine();
    // TODO Review what is necessary for the case of an empty model
    // for (String target : m_targetValues) {
    // SupportVectorMachine svm =
    // svmModel.addNewSupportVectorMachine();
    // svm.setTargetCategory(target);
    // SupportVectors supportVectors = svm.addNewSupportVectors();
    // supportVectors.setNumberOfSupportVectors(
    // BigInteger.valueOf(0));
    // }
    } else {
        for (Svm svm : m_svms) {
            SupportVectorMachine pmmlSvm = svmModel.addNewSupportVectorMachine();
            pmmlSvm.setTargetCategory(svm.getPositive());
            final boolean binaryClassification = (m_svms.size() == 2);
            if (binaryClassification) {
                pmmlSvm.setAlternateTargetCategory(m_svms.get(1).getPositive());
            }
            // add support vectors
            SupportVectors pmmlSupportVectors = pmmlSvm.addNewSupportVectors();
            DoubleVector[] supVectors = svm.getSupportVectors();
            pmmlSupportVectors.setNumberOfAttributes(BigInteger.valueOf(supVectors[0].getNumberValues()));
            pmmlSupportVectors.setNumberOfSupportVectors(BigInteger.valueOf(supVectors.length));
            for (int i = 0; i < supVectors.length; i++) {
                SupportVector pmmlSupportVector = pmmlSupportVectors.addNewSupportVector();
                pmmlSupportVector.setVectorId(getSupportVectorId(supVectors[i]));
            }
            // ----------------------------------------
            // add coefficients
            Coefficients pmmlCoefficients = pmmlSvm.addNewCoefficients();
            double[] alphas = svm.getTargetAlphas();
            pmmlCoefficients.setNumberOfCoefficients(BigInteger.valueOf(alphas.length));
            pmmlCoefficients.setAbsoluteValue(svm.getThreshold());
            for (int i = 0; i < alphas.length; i++) {
                Coefficient pmmlCoefficient = pmmlCoefficients.addNewCoefficient();
                /* KNIME defines the winner as the positive side of the
                     * threshold, but the DMG defines the winner as the negative
                     * side of the threshold. Therefore, to avoid changing KNIME
                     * algorithm, we need to add an additional minus sign for
                     * each svm output. When importing the PMML into KNIME
                     * the absolute value of the alphas is read. Hence the
                     * negative sign in the PMML alpha has no influence on
                     * the KNIME model.*/
                pmmlCoefficient.setValue(-1 * alphas[i]);
            }
            if (binaryClassification) {
                /* Binary classification case. Only one SVM is needed. */
                break;
            }
        }
    }
}

Example 2 with Coefficients

use of org.dmg.pmml.CoefficientsDocument.Coefficients in project knime-core by knime.

the class PMMLSVMTranslator method initSVMs.

/**
 * @param svmModel
 */
private void initSVMs(final SupportVectorMachineModel svmModel) {
    final Map<String, ArrayList<Double>> vectors = new LinkedHashMap<String, ArrayList<Double>>();
    for (VectorInstance vectorInstance : svmModel.getVectorDictionary().getVectorInstanceArray()) {
        REALSparseArray sparseArray = vectorInstance.getREALSparseArray1();
        ArrayList<Double> values = new ArrayList<Double>();
        for (Object realEntry : sparseArray.getREALEntries()) {
            values.add((Double) realEntry);
        }
        vectors.put(vectorInstance.getId(), values);
    }
    for (SupportVectorMachine supportVectorMachine : svmModel.getSupportVectorMachineArray()) {
        // collect support vectors
        SupportVectors svs = supportVectorMachine.getSupportVectors();
        DoubleVector[] supportVectors = new DoubleVector[svs.getNumberOfSupportVectors().intValue()];
        SupportVector[] supportVectorArray = svs.getSupportVectorArray();
        for (int i = 0; i < supportVectorArray.length; i++) {
            SupportVector supportVector = supportVectorArray[i];
            String vectorId = supportVector.getVectorId();
            String classValue = getClassValue(vectorId);
            supportVectors[i] = new DoubleVector(new RowKey(vectorId), vectors.get(vectorId), classValue);
        }
        Coefficients coef = supportVectorMachine.getCoefficients();
        double threshold = coef.getAbsoluteValue();
        // collect coefficients
        Coefficient[] coefficientArray = coef.getCoefficientArray();
        double[] alpha = new double[coefficientArray.length];
        for (int i = 0; i < coefficientArray.length; i++) {
            /**
             * The alpha in KNIME is always positive. When calculating the
             * distance it is multiplied with a target factor that is 1 or
             * -1 depending on whether we have a positive example or not.
             * (see {@link SVM#getTargetAlphas()} for details)
             */
            alpha[i] = Math.abs(coefficientArray[i].getValue());
        }
        m_svms.add(new Svm(supportVectors, alpha, supportVectorMachine.getTargetCategory(), threshold, m_kernel));
        /* The KNIME internal representation requires two SVMs for the
             * binary classification case. Therefore add a second SVM with the
             * same configuration as the first one except for the negative
             * threshold. */
        if (svmModel.getSupportVectorMachineArray().length == 1) {
            m_svms.add(new Svm(supportVectors.clone(), alpha, supportVectorMachine.getAlternateTargetCategory(), threshold * -1, m_kernel));
        }
    }
}