Example usage for org.apache.mahout.math.function VectorFunction VectorFunction

List of usage examples for org.apache.mahout.math.function VectorFunction VectorFunction

Introduction

In this page you can find the example usage for org.apache.mahout.math.function VectorFunction VectorFunction.

Prototype

VectorFunction

Source Link

Usage

From source file:com.mapr.stats.bandit.ContextualBayesBandit.java

License:Apache License

private Vector sampleNoLink() {
    final Vector theta = state.aggregateRows(new VectorFunction() {
        final DoubleFunction inverseLink = new InverseLogisticFunction();

        @Override/*  ww  w.  java  2  s .  co  m*/
        public double apply(Vector f) {
            return inverseLink.apply(rand.nextDouble(f.get(0), f.get(1)));
        }
    });
    return featureMap.times(theta);
}

From source file:org.qcri.pca.SPCADriver.java

/**
 * Run PPCA sequentially given the small input Y which fit into memory This
 * could be used also on sampled data from a distributed matrix
 * // ww  w  .j a v  a 2  s .  c o  m
 * Note: this implementation ignore NaN values by replacing them with 0
 * 
 * @param conf
 *          the configuration
 * @param centralY
 *          the input matrix
 * @param initVal
 *          the initial values for C and ss
 * @param MAX_ROUNDS
 *          maximum number of iterations
 * @return the error
 * @throws Exception
 */
double runSequential(Configuration conf, Matrix centralY, InitialValues initVal, final int MAX_ROUNDS)
        throws Exception {
    Matrix centralC = initVal.C;
    double ss = initVal.ss;
    final int nRows = centralY.numRows();
    final int nCols = centralY.numCols();
    final int nPCs = centralC.numCols();
    final float threshold = 0.00001f;

    log.info("tracec= " + PCACommon.trace(centralC));
    //ignore NaN elements by replacing them with 0
    for (int r = 0; r < nRows; r++)
        for (int c = 0; c < nCols; c++)
            if (new Double(centralY.getQuick(r, c)).isNaN()) {
                centralY.setQuick(r, c, 0);
            }

    //centralize and normalize the input matrix
    Vector mean = centralY.aggregateColumns(new VectorFunction() {
        @Override
        public double apply(Vector v) {
            return v.zSum() / nRows;
        }
    });
    //also normalize the matrix by dividing each element by its columns range
    Vector spanVector = new DenseVector(nCols);
    for (int c = 0; c < nCols; c++) {
        Vector col = centralY.viewColumn(c);
        double max = col.maxValue();
        double min = col.minValue();
        double span = max - min;
        spanVector.setQuick(c, span);
    }
    for (int r = 0; r < nRows; r++)
        for (int c = 0; c < nCols; c++)
            centralY.set(r, c, (centralY.get(r, c) - mean.get(c))
                    / (spanVector.getQuick(c) != 0 ? spanVector.getQuick(c) : 1));

    Matrix centralCtC = centralC.transpose().times(centralC);
    log.info("tracectc= " + PCACommon.trace(centralCtC));
    log.info("traceinvctc= " + PCACommon.trace(inv(centralCtC)));
    log.info("traceye= " + PCACommon.trace(centralY));
    log.info("SSSSSSSSSSSSSSSSSSSSSSSSSSSS " + ss);

    int count = 1;
    // old = Inf;
    double old = Double.MAX_VALUE;
    // -------------------------- EM Iterations
    // while count
    Matrix centralX = null;
    int round = 0;
    while (round < MAX_ROUNDS && count > 0) {
        round++;
        // Sx = inv( eye(d) + CtC/ss );
        Matrix Sx = eye(nPCs).times(ss).plus(centralCtC);
        Sx = inv(Sx);
        // X = Ye*C*(Sx/ss);
        centralX = centralY.times(centralC).times(Sx.transpose());
        // XtX = X'*X + ss * Sx;
        Matrix centralXtX = centralX.transpose().times(centralX).plus(Sx.times(ss));
        // C = (Ye'*X) / XtX;
        Matrix tmpInv = inv(centralXtX);
        centralC = centralY.transpose().times(centralX).times(tmpInv);
        // CtC = C'*C;
        centralCtC = centralC.transpose().times(centralC);
        // ss = ( sum(sum( (X*C'-Ye).^2 )) + trace(XtX*CtC) - 2*xcty ) /(N*D);
        double norm2 = centralY.clone().assign(new DoubleFunction() {
            @Override
            public double apply(double arg1) {
                return arg1 * arg1;
            }
        }).zSum();
        ss = norm2 + PCACommon.trace(centralXtX.times(centralCtC));
        //ss3 = sum (X(i:0) * C' * Y(i,:)')
        DenseVector resVector = new DenseVector(nCols);
        double xctyt = 0;
        for (int i = 0; i < nRows; i++) {
            PCACommon.vectorTimesMatrixTranspose(centralX.viewRow(i), centralC, resVector);
            double res = resVector.dot(centralY.viewRow(i));
            xctyt += res;
        }
        ss -= 2 * xctyt;
        ss /= (nRows * nCols);

        log.info("SSSSSSSSSSSSSSSSSSSSSSSSSSSS " + ss);
        double traceSx = PCACommon.trace(Sx);
        double traceX = PCACommon.trace(centralX);
        double traceSumXtX = PCACommon.trace(centralXtX);
        double traceC = PCACommon.trace(centralC);
        double traceCtC = PCACommon.trace(centralCtC);
        log.info("TTTTTTTTTTTTTTTTT " + traceSx + " " + traceX + " " + traceSumXtX + " " + traceC + " "
                + traceCtC + " " + 0);

        double objective = ss;
        double rel_ch = Math.abs(1 - objective / old);
        old = objective;
        count++;
        if (rel_ch < threshold && count > 5)
            count = 0;
        log.info("Objective:  %.6f    relative change: %.6f \n", objective, rel_ch);
    }

    double norm1Y = centralY.aggregateColumns(new VectorNorm1()).maxValue();
    log.info("Norm1 of Ye is: " + norm1Y);
    Matrix newYerror = centralY.minus(centralX.times(centralC.transpose()));
    double norm1Err = newYerror.aggregateColumns(new VectorNorm1()).maxValue();
    log.info("Norm1 of the reconstruction error is: " + norm1Err);

    initVal.C = centralC;
    initVal.ss = ss;
    return norm1Err / norm1Y;
}

From source file:org.qcri.pca.SPCADriver.java

/**
 * Run PPCA sequentially given the small input Y which fit into memory This
 * could be used also on sampled data from a distributed matrix
 * //w w w.  j a  va  2 s.  com
 * Note: this implementation ignore NaN values by replacing them with 0
 * 
 * @param conf
 *          the configuration
 * @param centralY
 *          the input matrix
 * @param initVal
 *          the initial values for C and ss
 * @param MAX_ROUNDS
 *          maximum number of iterations
 * @return the error
 * @throws Exception
 */
double runSequential_JacobVersion(Configuration conf, Matrix centralY, InitialValues initVal,
        final int MAX_ROUNDS) {
    Matrix centralC = initVal.C;// the current implementation doesn't use initial ss of
    // initVal
    final int nRows = centralY.numRows();
    final int nCols = centralY.numCols();
    final int nPCs = centralC.numCols();
    final float threshold = 0.00001f;

    log.info("tracec= " + PCACommon.trace(centralC));
    // Y = Y - mean(Ye)
    // Also normalize the matrix
    for (int r = 0; r < nRows; r++)
        for (int c = 0; c < nCols; c++)
            if (new Double(centralY.getQuick(r, c)).isNaN()) {
                centralY.setQuick(r, c, 0);
            }
    Vector mean = centralY.aggregateColumns(new VectorFunction() {
        @Override
        public double apply(Vector v) {
            return v.zSum() / nRows;
        }
    });
    Vector spanVector = new DenseVector(nCols);
    for (int c = 0; c < nCols; c++) {
        Vector col = centralY.viewColumn(c);
        double max = col.maxValue();
        double min = col.minValue();
        double span = max - min;
        spanVector.setQuick(c, span);
    }
    for (int r = 0; r < nRows; r++)
        for (int c = 0; c < nCols; c++)
            centralY.set(r, c, (centralY.get(r, c) - mean.get(c))
                    / (spanVector.getQuick(c) != 0 ? spanVector.getQuick(c) : 1));

    // -------------------------- initialization
    // CtC = C'*C;
    Matrix centralCtC = centralC.transpose().times(centralC);
    log.info("tracectc= " + PCACommon.trace(centralCtC));
    log.info("traceinvctc= " + PCACommon.trace(inv(centralCtC)));
    log.info("traceye= " + PCACommon.trace(centralY));
    // X = Ye * C * inv(CtC);
    Matrix centralX = centralY.times(centralC).times(inv(centralCtC));
    log.info("tracex= " + PCACommon.trace(centralX));
    // recon = X * C';
    Matrix recon = centralX.times(centralC.transpose());
    log.info("tracerec= " + PCACommon.trace(recon));
    // ss = sum(sum((recon-Ye).^2)) / (N*D-missing);
    double ss = recon.minus(centralY).assign(new DoubleFunction() {
        @Override
        public double apply(double arg1) {
            return arg1 * arg1;
        }
    }).zSum() / (nRows * nCols);
    log.info("SSSSSSSSSSSSSSSSSSSSSSSSSSSS " + ss);

    int count = 1;
    // old = Inf;
    double old = Double.MAX_VALUE;
    // -------------------------- EM Iterations
    // while count
    int round = 0;
    while (round < MAX_ROUNDS && count > 0) {
        round++;
        // ------------------ E-step, (co)variances
        // Sx = inv( eye(d) + CtC/ss );
        Matrix centralSx = eye(nPCs).plus(centralCtC.divide(ss));
        centralSx = inv(centralSx);
        // ------------------ E-step expected value
        // X = Ye*C*(Sx/ss);
        centralX = centralY.times(centralC).times(centralSx.divide(ss));
        // ------------------ M-step
        // SumXtX = X'*X;
        Matrix centralSumXtX = centralX.transpose().times(centralX);
        // C = (Ye'*X) / (SumXtX + N*Sx );
        Matrix tmpInv = inv(centralSumXtX.plus(centralSx.times(nRows)));
        centralC = centralY.transpose().times(centralX).times(tmpInv);
        // CtC = C'*C;
        centralCtC = centralC.transpose().times(centralC);
        // ss = ( sum(sum( (X*C'-Ye).^2 )) + N*sum(sum(CtC.*Sx)) +
        // missing*ss_old ) /(N*D);
        recon = centralX.times(centralC.transpose());
        double error = recon.minus(centralY).assign(new DoubleFunction() {
            @Override
            public double apply(double arg1) {
                return arg1 * arg1;
            }
        }).zSum();
        ss = error + nRows * dot(centralCtC.clone(), centralSx).zSum();
        ss /= (nRows * nCols);

        log.info("SSSSSSSSSSSSSSSSSSSSSSSSSSSS " + ss);
        double traceSx = PCACommon.trace(centralSx);
        double traceX = PCACommon.trace(centralX);
        double traceSumXtX = PCACommon.trace(centralSumXtX);
        double traceC = PCACommon.trace(centralC);
        double traceCtC = PCACommon.trace(centralCtC);
        log.info("TTTTTTTTTTTTTTTTT " + traceSx + " " + traceX + " " + traceSumXtX + " " + traceC + " "
                + traceCtC + " " + 0);

        // objective = N*D + N*(D*log(ss) +PCACommon.trace(Sx)-log(det(Sx)) )
        // +PCACommon.trace(SumXtX) -missing*log(ss_old);
        double objective = nRows * nCols + nRows
                * (nCols * Math.log(ss) + PCACommon.trace(centralSx) - Math.log(centralSx.determinant()))
                + PCACommon.trace(centralSumXtX);
        double rel_ch = Math.abs(1 - objective / old);
        old = objective;
        count++;
        if (rel_ch < threshold && count > 5)
            count = 0;
        System.out.printf("Objective:  %.6f    relative change: %.6f \n", objective, rel_ch);
    }

    double norm1Y = centralY.aggregateColumns(new VectorNorm1()).maxValue();
    log.info("Norm1 of Y is: " + norm1Y);
    Matrix newYerror = centralY.minus(centralX.times(centralC.transpose()));
    double norm1Err = newYerror.aggregateColumns(new VectorNorm1()).maxValue();
    log.info("Norm1 of the reconstruction error is: " + norm1Err);

    initVal.C = centralC;
    initVal.ss = ss;
    return norm1Err / norm1Y;
}