org.apache.solr.client.solrj.io.eval.TransposeEvaluator.java Source code

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Here is the source code for org.apache.solr.client.solrj.io.eval.TransposeEvaluator.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.solr.client.solrj.io.eval;

import java.io.IOException;

import java.util.Locale;

import org.apache.commons.math3.linear.Array2DRowRealMatrix;
import org.apache.solr.client.solrj.io.stream.expr.StreamExpression;
import org.apache.solr.client.solrj.io.stream.expr.StreamFactory;

public class TransposeEvaluator extends RecursiveObjectEvaluator implements OneValueWorker {
    protected static final long serialVersionUID = 1L;

    public TransposeEvaluator(StreamExpression expression, StreamFactory factory) throws IOException {
        super(expression, factory);

        if (1 != containedEvaluators.size()) {
            throw new IOException(
                    String.format(Locale.ROOT, "Invalid expression %s - expecting exactly 1 value but found %d",
                            expression, containedEvaluators.size()));
        }
    }

    @Override
    public Object doWork(Object value) throws IOException {
        if (null == value) {
            return null;
        } else if (value instanceof Matrix) {
            Matrix matrix = (Matrix) value;
            double[][] data = matrix.getData();
            Array2DRowRealMatrix amatrix = new Array2DRowRealMatrix(data);
            Array2DRowRealMatrix tmatrix = (Array2DRowRealMatrix) amatrix.transpose();
            return new Matrix(tmatrix.getData());
        } else {
            throw new IOException("matrix parameter expected for transpose function");
        }
    }
}