001 /* 002 * Copyright (C) 2008-2010 by Holger Arndt 003 * 004 * This file is part of the Universal Java Matrix Package (UJMP). 005 * See the NOTICE file distributed with this work for additional 006 * information regarding copyright ownership and licensing. 007 * 008 * UJMP is free software; you can redistribute it and/or modify 009 * it under the terms of the GNU Lesser General Public License as 010 * published by the Free Software Foundation; either version 2 011 * of the License, or (at your option) any later version. 012 * 013 * UJMP is distributed in the hope that it will be useful, 014 * but WITHOUT ANY WARRANTY; without even the implied warranty of 015 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 016 * GNU Lesser General Public License for more details. 017 * 018 * You should have received a copy of the GNU Lesser General Public 019 * License along with UJMP; if not, write to the 020 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, 021 * Boston, MA 02110-1301 USA 022 */ 023 024 package org.ujmp.core.util; 025 026 import java.util.Iterator; 027 028 import org.ujmp.core.Matrix; 029 import org.ujmp.core.exceptions.MatrixException; 030 031 public class CoordinateIterator2D implements Iterable<long[]> { 032 033 private static final int ROW = Matrix.ROW; 034 035 private static final int COLUMN = Matrix.COLUMN; 036 037 private long[] size = null; 038 039 public CoordinateIterator2D(long... size) { 040 this.size = size; 041 if (size.length > 2) { 042 new Exception( 043 "warning: using a 2d iterator on a matrix or calculation that has more than 2 dimensions, results may be wrong") 044 .printStackTrace(); 045 } 046 } 047 048 public Iterator<long[]> iterator() { 049 return new Iterator<long[]>() { 050 051 long[] cursor = new long[] { 0, -1 }; 052 053 long columnCount = size[COLUMN]; 054 055 long rowCount = size[ROW]; 056 057 long rowMinus1 = rowCount - 1; 058 059 long columnMinus1 = columnCount - 1; 060 061 boolean isNotEmpty = columnCount != 0 && rowCount != 0; 062 063 public boolean hasNext() { 064 return (cursor[ROW] != rowMinus1 || cursor[COLUMN] != columnMinus1) && isNotEmpty; 065 } 066 067 public long[] next() { 068 return ++cursor[COLUMN] == columnCount && (cursor[COLUMN] = 0) == ++cursor[ROW] ? cursor 069 : cursor; 070 } 071 072 public void remove() { 073 throw new MatrixException("not implemented"); 074 } 075 }; 076 } 077 078 }