org.apache.sysml.runtime.instructions.spark.functions.MatrixVectorBinaryOpPartitionFunction.java Source code

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Here is the source code for org.apache.sysml.runtime.instructions.spark.functions.MatrixVectorBinaryOpPartitionFunction.java

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/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package org.apache.sysml.runtime.instructions.spark.functions;

import java.util.Iterator;

import org.apache.spark.api.java.function.PairFlatMapFunction;

import scala.Tuple2;

import org.apache.sysml.lops.BinaryM.VectorType;
import org.apache.sysml.runtime.instructions.spark.data.LazyIterableIterator;
import org.apache.sysml.runtime.instructions.spark.data.PartitionedBroadcast;
import org.apache.sysml.runtime.matrix.data.MatrixBlock;
import org.apache.sysml.runtime.matrix.data.MatrixIndexes;
import org.apache.sysml.runtime.matrix.operators.BinaryOperator;

public class MatrixVectorBinaryOpPartitionFunction
        implements PairFlatMapFunction<Iterator<Tuple2<MatrixIndexes, MatrixBlock>>, MatrixIndexes, MatrixBlock> {
    private static final long serialVersionUID = 9096091404578628534L;

    private BinaryOperator _op = null;
    private PartitionedBroadcast<MatrixBlock> _pmV = null;
    private VectorType _vtype = null;

    public MatrixVectorBinaryOpPartitionFunction(BinaryOperator op, PartitionedBroadcast<MatrixBlock> binput,
            VectorType vtype) {
        _op = op;
        _pmV = binput;
        _vtype = vtype;
    }

    @Override
    public LazyIterableIterator<Tuple2<MatrixIndexes, MatrixBlock>> call(
            Iterator<Tuple2<MatrixIndexes, MatrixBlock>> arg0) throws Exception {
        return new MapBinaryPartitionIterator(arg0);
    }

    /**
     * Lazy mbinary iterator to prevent materialization of entire partition output in-memory.
     * The implementation via mapPartitions is required to preserve partitioning information,
     * which is important for performance. 
     */
    private class MapBinaryPartitionIterator extends LazyIterableIterator<Tuple2<MatrixIndexes, MatrixBlock>> {
        public MapBinaryPartitionIterator(Iterator<Tuple2<MatrixIndexes, MatrixBlock>> in) {
            super(in);
        }

        @Override
        protected Tuple2<MatrixIndexes, MatrixBlock> computeNext(Tuple2<MatrixIndexes, MatrixBlock> arg)
                throws Exception {
            //unpack partition key-value pairs
            MatrixIndexes ix = arg._1();
            MatrixBlock in1 = arg._2();

            //get the rhs block 
            int rix = (int) ((_vtype == VectorType.COL_VECTOR) ? ix.getRowIndex() : 1);
            int cix = (int) ((_vtype == VectorType.COL_VECTOR) ? 1 : ix.getColumnIndex());
            MatrixBlock in2 = _pmV.getBlock(rix, cix);

            //execute the binary operation
            MatrixBlock ret = (MatrixBlock) (in1.binaryOperations(_op, in2, new MatrixBlock()));
            return new Tuple2<>(ix, ret);
        }
    }
}