/*
* GeoTools - The Open Source Java GIS Toolkit
* http://geotools.org
*
* (C) 2005-2008, Open Source Geospatial Foundation (OSGeo)
*
* 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.referencing.operation.matrix;
import java.io.Serializable;
import javax.vecmath.SingularMatrixException;
import org.opengis.referencing.operation.Matrix;
import org.geotools.resources.i18n.Errors;
import org.geotools.resources.i18n.ErrorKeys;
/**
* 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 $URL$
* @version $Id$
* @author Martin Desruisseaux (IRD)
*/
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(Errors.format(ErrorKeys.ILLEGAL_MATRIX_SIZE));
}
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(Errors.format(ErrorKeys.ILLEGAL_MATRIX_SIZE));
}
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);
}
}
}