ludecomposition.java

一个关于java 的常用工具包

package org.jutil.math.matrix;
/**
 * <p>This class represents an LU factorization of a matrix.</p>
 * <p>P*A = L*U</p>
 *
 * @path    $Source: /cvsroot/org-jutil/jutil.org/src/org/jutil/math/matrix/LUDecomposition.java,v $
 * @version $Revision: 1.4 $
 * @date    $Date: 2002/07/02 14:27:31 $
 * @state   $State: Exp $
 * @author  Marko van Dooren
 * @release $Name:  $
 */
public interface LUDecomposition {

	/* The revision of this class */
	public final static String CVS_REVISION ="$Revision: 1.4 $";

 /*@
	 @ private invariant L().sameDimensions(U());
	 @ private invariant P().sameDimensions(U());
	 @*/
	
	/**
	 * Return the L matrix of this LU factorization.
	 */
 /*@
   @ public behavior
	 @
	 @ post \result != null;
	 @ post \result.isSquare();
	 @ post \result.isLowerTriangular();
	 @ post (\forall int i; i>=1 && i<=\result.getNbColumns();
	 @         \result.elementAt(i,i) == 1);
	 @*/
	public Matrix L();
	
	/**
	 * Return the U matrix of this LU factorization.
	 */
 /*@
   @ public behavior
	 @
	 @ post \result != null;
	 @ post \result.isSquare();
	 @ post \result.isUpperTriangular();
	 @*/
	public Matrix U();
	
	/**
	 * Return the P matrix of this LU factorization.
	 */
 /*@
   @ public behavior
	 @
	 @ post \result != null;
	 @ post \result.isPermutationMatrix();
	 @*/
	public Matrix P();
	
}

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behalf of the JUTIL.ORG Project. The copyright is dated by the dates 
after the "@date" tags above. All rights reserved.
This software is published under the terms of the JUTIL.ORG Software
License version 1.1 or later, a copy of which has been included with
this distribution in the LICENSE file, which can also be found at
http://www.jutil.org/LICENSE. This software is distributed WITHOUT 
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 
or FITNESS FOR A PARTICULAR PURPOSE. See the JUTIL.ORG Software 
License for more details.
For more information, please see http://jutil.org/</copyright>*/