Example usage for org.apache.mahout.math DenseMatrix viewRow

Introduction

In this page you can find the example usage for org.apache.mahout.math DenseMatrix viewRow.

Prototype

@Override
    public Vector viewRow(int row) 

Source Link

Usage

From source file:com.twitter.algebra.AlgebraCommon.java

License:Apache License

/***
 * If the MapDir matrix is small, we can convert it to an in memory representation
 * and then run efficient centralized operations
 * /* w w  w.jav  a2s.  co m*/
 * @param origMtx in MapDir format (generated by MatrixOutputFormat)
 * @return a dense matrix including the data
 * @throws IOException 
 */
public static DenseMatrix toDenseMatrix(DistributedRowMatrix origMtx) throws IOException {
    MapDir mapDir = new MapDir(new Configuration(), origMtx.getRowPath());
    DenseMatrix mtx = new DenseMatrix(origMtx.numRows(), origMtx.numCols());
    Iterator<MatrixSlice> sliceIterator;
    try {
        sliceIterator = mapDir.iterateAll();
    } catch (Exception e) {
        log.info(e.toString());
        log.info("Input is not in matrix format, trying SequenceFileFormat instead ...");
        sliceIterator = origMtx.iterateAll();
    }
    while (sliceIterator.hasNext()) {
        MatrixSlice slice = sliceIterator.next();
        //      int r = slice.index();
        //      for (int c = 0; c < mtx.numCols(); c++) {
        //        mtx.set(r, c, slice.get(c));
        //      }
        mtx.viewRow(slice.index()).assign(slice.vector());
    }
    mapDir.close();
    return mtx;
}

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

/***
 * If the matrix is small, we can convert it to an in memory representation
 * and then run efficient centralized operations
 * /*  ww  w . j  a  v a2  s  . co m*/
 * @param origMtx
 * @return a dense matrix including the data
 */
static DenseMatrix toDenseMatrix(DistributedRowMatrix origMtx) {
    DenseMatrix mtx = new DenseMatrix(origMtx.numRows(), origMtx.numCols());
    Iterator<MatrixSlice> sliceIterator = origMtx.iterateAll();
    while (sliceIterator.hasNext()) {
        MatrixSlice slice = sliceIterator.next();
        mtx.viewRow(slice.index()).assign(slice.vector());
    }
    return mtx;
}

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

private static DenseMatrix toDenseMatrix(Matrix origMtx) {
    DenseMatrix mtx = new DenseMatrix(origMtx.numRows(), origMtx.numCols());
    Iterator<MatrixSlice> sliceIterator = origMtx.iterateAll();
    while (sliceIterator.hasNext()) {
        MatrixSlice slice = sliceIterator.next();
        mtx.viewRow(slice.index()).assign(slice.vector());
    }/*  ww w .  ja  va 2s  .  c o  m*/
    return mtx;
}

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From source file:org.qcri.sparkpca.PCAUtils.java

/**
 * Convert abstract matrix to dense matrix
 *///ww w.j  a v a  2 s  .  c o  m
private static DenseMatrix toDenseMatrix(Matrix origMtx) {
    DenseMatrix mtx = new DenseMatrix(origMtx.numRows(), origMtx.numCols());
    Iterator<MatrixSlice> sliceIterator = origMtx.iterateAll();
    while (sliceIterator.hasNext()) {
        MatrixSlice slice = sliceIterator.next();
        mtx.viewRow(slice.index()).assign(slice.vector());
    }
    return mtx;
}

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