001    /*
002     * Licensed to the Apache Software Foundation (ASF) under one or more
003     * contributor license agreements.  See the NOTICE file distributed with
004     * this work for additional information regarding copyright ownership.
005     * The ASF licenses this file to You under the Apache License, Version 2.0
006     * (the "License"); you may not use this file except in compliance with
007     * the License.  You may obtain a copy of the License at
008     *
009     *      http://www.apache.org/licenses/LICENSE-2.0
010     *
011     * Unless required by applicable law or agreed to in writing, software
012     * distributed under the License is distributed on an "AS IS" BASIS,
013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     * See the License for the specific language governing permissions and
015     * limitations under the License.
016     */
017    
018    package org.apache.commons.math3.linear;
019    
020    import org.apache.commons.math3.exception.MathIllegalArgumentException;
021    import org.apache.commons.math3.exception.util.LocalizedFormats;
022    
023    /**
024     * Exception to be thrown when a self-adjoint {@link RealLinearOperator}
025     * is expected.
026     * Since the coefficients of the matrix are not accessible, the most
027     * general definition is used to check that A is not self-adjoint, i.e.
028     * there exist x and y such as {@code | x' A y - y' A x | >= eps},
029     * where {@code eps} is a user-specified tolerance, and {@code x'}
030     * denotes the transpose of {@code x}.
031     * In the terminology of this exception, {@code A} is the "offending"
032     * linear operator, {@code x} and {@code y} are the first and second
033     * "offending" vectors, respectively.
034     *
035     * @version $Id: NonSelfAdjointOperatorException.java 1416643 2012-12-03 19:37:14Z tn $
036     * @since 3.0
037     */
038    public class NonSelfAdjointOperatorException
039        extends MathIllegalArgumentException {
040        /** Serializable version Id. */
041        private static final long serialVersionUID = 1784999305030258247L;
042    
043        /** Creates a new instance of this class. */
044        public NonSelfAdjointOperatorException() {
045            super(LocalizedFormats.NON_SELF_ADJOINT_OPERATOR);
046        }
047    }