Application: gvSIG desktop

/*

 *    GeoTools - OpenSource mapping toolkit

 *    http://geotools.org

 *    (C) 2005-2006, GeoTools Project Managment Committee (PMC)

 *    (C) 2005, Institut de Recherche pour le Développement

 *

 *    This library 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;

 *    version 2.1 of the License.

 *

 *    This library 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.

 */

package org.geotools.referencefork.referencing.operation.matrix;

import java.io.Serializable;

import javax.vecmath.SingularMatrixException;

import org.opengis.referencing.operation.Matrix;

/**

 * A matrix of fixed {@value #SIZE}×{@value #SIZE} size. This trivial matrix is returned as a

 * result of {@linkplain org.opengis.referencing.operation.MathTransform1D} derivative computation.

 *

 * @since 2.2

 * @source $URL: http://svn.geotools.org/geotools/trunk/gt/modules/library/referencing/src/main/java/org/geotools/referencing/operation/matrix/Matrix1.java $

 * @version $Id: Matrix1.java 29769 2008-04-02 17:10:40Z desruisseaux $

 * @author Martin Desruisseaux

 */

public class Matrix1 implements XMatrix, Serializable {

    /** Serial number for interoperability with different versions. */

    private static final long serialVersionUID = -4829171016106097031L;

    /** The only element in this matrix. */

    public double m00;

    /** The matrix size, which is {@value}. */

    public static final int SIZE = 1;

    /**

     * Creates a new identity matrix.

     */

    public Matrix1() {

        m00 = 1;

    }

    /**

     * Creates a new matrix initialized to the specified value.

     */

    public Matrix1(final double m00) {

        this.m00 = m00;

    }

    /**

     * Creates a new matrix initialized to the same value than the specified one.

     * The specified matrix size must be {@value #SIZE}×{@value #SIZE}.

     */

    public Matrix1(final Matrix matrix) {

        if (matrix.getNumRow()!=SIZE || matrix.getNumCol()!=SIZE) {

            throw new IllegalArgumentException();

        }

        m00 = matrix.getElement(0,0);

    }

    /**

     * Returns the number of rows in this matrix, which is always {@value #SIZE}

     * in this implementation.

     */

    public final int getNumRow() {

        return SIZE;

    }

    /**

     * Returns the number of colmuns in this matrix, which is always {@value #SIZE}

     * in this implementation.

     */

    public final int getNumCol() {

        return SIZE;

    }

    /**

     * {@inheritDoc}

     */

    public final double getElement(final int row, final int col) {

        if (row==0 && col==0) {

            return m00;

        } else {

            throw new IndexOutOfBoundsException();

        }

    }

    /**

     * {@inheritDoc}

     */

    public final void setElement(final int row, final int col, final double value) {

        if (row==0 && col==0) {

            m00 = value;

        } else {

            throw new IndexOutOfBoundsException();

        }

    }

    /**

     * {@inheritDoc}

     */

    public final void setZero() {

        m00 = 0;

    }

    /**

     * {@inheritDoc}

     */

    public final void setIdentity() {

        m00 = 1;

    }

    /**

     * {@inheritDoc}

     */

    public final boolean isIdentity() {

        return m00 == 1;

    }

    /**

     * {@inheritDoc}

     */

    public final boolean isIdentity(double tolerance) {

            return Math.abs(m00 - 1) <= Math.abs(tolerance);

    }

    /**

     * {@inheritDoc}

     */

    public final boolean isAffine() {

        return m00==1;

    }

    /**

     * {@inheritDoc}

     */

    public final void negate() {

        m00 = -m00;

    }

    /**

     * {@inheritDoc}

     */

    public final void transpose() {

        // Nothing to do for a 1x1 matrix.

    }

    /**

     * Inverts this matrix in place.

     */

    public final void invert() {

        if (m00 == 0) {

            throw new SingularMatrixException();

        }

        m00 = 1/m00;

    }

    /**

     * {@inheritDoc}

     */

    public final void multiply(final Matrix matrix) {

        if (matrix.getNumRow()!=SIZE || matrix.getNumCol()!=SIZE) {

            throw new IllegalArgumentException();

        }

        m00 *= matrix.getElement(0,0);

    }

    /**

     * {@inheritDoc}

     */

    public boolean equals(final Matrix matrix, final double tolerance) {

        return GeneralMatrix.epsilonEquals(this, matrix, tolerance);

    }

    /**

     * Returns {@code true} if the specified object is of type {@code Matrix1} and

     * all of the data members are equal to the corresponding data members in this matrix.

     */

    @Override

    public boolean equals(final Object object) {

        if (object!=null && object.getClass().equals(getClass())) {

            final Matrix1 that = (Matrix1) object;

            return Double.doubleToLongBits(this.m00) == Double.doubleToLongBits(that.m00);

        }

        return false;

    }

    /**

     * Returns a hash code value based on the data values in this object.

     */

    @Override

    public int hashCode() {

        return (int)(Double.doubleToLongBits(m00) ^ serialVersionUID);

    }

    /**

     * Returns a string representation of this matrix. The returned string is implementation

     * dependent. It is usually provided for debugging purposes only.

     */

//    @Override

//    public String toString() {

//        return GeneralMatrix.toString(this);

//    }

    /**

     * Returns a clone of this matrix.

     */

    @Override

    public Matrix1 clone() {

        try {

            return (Matrix1) super.clone();

        } catch (CloneNotSupportedException e) {

            // Should not happen, since we are cloneable.

            throw new AssertionError(e);

        }

    }

}