Example usage for org.apache.commons.math.linear RealMatrix getNorm

Introduction

In this page you can find the example usage for org.apache.commons.math.linear RealMatrix getNorm.

Prototype

double getNorm();

Source Link

Document

Returns the <a href="http://mathworld.wolfram.com/MaximumAbsoluteRowSumNorm.html"> maximum absolute row sum norm</a> of the matrix.

Usage

From source file:net.sf.jtmt.similarity.matrix.JaccardSimilarity.java

@Override
public double computeSimilarity(RealMatrix source, RealMatrix target) {
    double intersection = 0.0D;
    for (int i = 0; i < source.getRowDimension(); i++) {
        intersection += Math.min(source.getEntry(i, 0), target.getEntry(i, 0));
    }/*from   w w  w. ja va  2 s.c  om*/
    if (intersection > 0.0D) {
        double union = source.getNorm() + target.getNorm() - intersection;
        return intersection / union;
    } else {
        return 0.0D;
    }
}

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From source file:net.sf.jtmt.similarity.matrix.CosineSimilarity.java

/**
 * Dot.//from w  ww .ja  va  2  s  .  co  m
 *
 * @param source the source
 * @param target the target
 * @return the double
 */
private double dot(RealMatrix source, RealMatrix target) {
    int maxRows = source.getRowDimension();
    int maxCols = source.getColumnDimension();
    RealMatrix dotProduct = new OpenMapRealMatrix(maxRows, maxCols);
    for (int row = 0; row < maxRows; row++) {
        for (int col = 0; col < maxCols; col++) {
            dotProduct.setEntry(row, col, source.getEntry(row, col) * target.getEntry(row, col));
        }
    }
    return dotProduct.getNorm();
}

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From source file:net.sf.jtmt.similarity.matrix.Searcher.java

/**
 * Gets the query matrix./*from   w w  w . j  a va  2s .  c o  m*/
 *
 * @param query the query
 * @return the query matrix
 */
private RealMatrix getQueryMatrix(String query) {
    RealMatrix queryMatrix = new OpenMapRealMatrix(terms.size(), 1);
    String[] queryTerms = query.split("\\s+");
    for (String queryTerm : queryTerms) {
        int termIdx = 0;
        for (String term : terms) {
            if (queryTerm.equalsIgnoreCase(term)) {
                queryMatrix.setEntry(termIdx, 0, 1.0D);
            }
            termIdx++;
        }
    }
    queryMatrix = queryMatrix.scalarMultiply(1 / queryMatrix.getNorm());
    return queryMatrix;
}

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