/* * 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.List; import org.ujmp.core.Matrix; import org.ujmp.core.util.MathUtil; public class Bootstrap extends AbstractObjectCalculation { private static final long serialVersionUID = -5084329826465538416L; private int count = 0; private Matrix selection = null; public Bootstrap(Matrix m) { this(m, (int) m.getRowCount()); } public Bootstrap(Matrix m, int count) { super(m); this.count = count; } public Object getObject(long... coordinates) { if (selection == null) { List<Integer> rows = new ArrayList<Integer>(); for (int i = 0; i < count; i++) { int s = MathUtil.nextInteger(0, (int) getSource().getRowCount()); rows.add(s); } selection = getSource().selectRows(Ret.LINK, rows); } return selection.getAsObject(coordinates); } @Override public long[] getSize() { return new long[] { count, getSource().getColumnCount() }; } }