/*
* Copyright (C) 2008-2015 by Holger Arndt
*
* This file is part of the Universal Java Matrix Package (UJMP).
* See the NOTICE file distributed with this work for additional
* information regarding copyright ownership and licensing.
*
* UJMP is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* UJMP is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with UJMP; if not, write to the
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301 USA
*/
package org.ujmp.core.objectmatrix.calculation;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import org.ujmp.core.Matrix;
public class Shuffle extends AbstractObjectCalculation {
private static final long serialVersionUID = -6935375114060680121L;
private Matrix selection = null;
public Shuffle(Matrix m) {
super(m);
}
public Object getObject(long... coordinates) {
if (selection == null) {
List<Integer> rows = new ArrayList<Integer>();
for (int i = 0; i < getSource().getRowCount(); i++) {
rows.add(i);
}
Collections.shuffle(rows);
selection = getSource().selectRows(Ret.LINK, rows);
}
return selection.getAsObject(coordinates);
}
}