GeneralMatrix changes for revisions 24484:24485

This commit is a copy-and-paste of the isIdentity() method that existed prior this commit, modified for working as a static method instead than a member method and with the following code added:

tolerance = Math.abs(tolerance);
...
Math.abs(... - ...) > tolerance

SIS has the same method in Matrices, with the tolerance = abs(tolerance) removed for consistency with equals(..., tolerance) methods and the abs(...) > tolerance inverted to !(abs(...) <= tolerance) for working with NaN. Since this is not original work, having this method in SIS is okay.

Command line:

svn diff --extensions "--unified --ignore-space-change --ignore-all-space --ignore-eol-style" -r24484:24485 https://svn.osgeo.org/geotools/trunk/modules/library/referencing/src/main/java/org/geotools/referencing/operation/matrix/GeneralMatrix.java
Revision 24484Revision 24485
private static final long serialVersionUID = 8447482612423035360L;

/**
 * Constructs a square identity matrix of size {@code size}&nbsp;&times;&nbsp;{@code size}.
 */
public GeneralMatrix(final int size) {
 
private static final long serialVersionUID = 8447482612423035360L;

/**
 * Defaul tolerance value for floating point comparisons.
 */
public static final double EPS = 1E-6;

/**
 * Constructs a square identity matrix of size {@code size}&nbsp;&times;&nbsp;{@code size}.
 */
public GeneralMatrix(final int size) {
    assert isAffine() : this;
    return true;
}

/**
 * {@inheritDoc}
 */
public final void multiply(final Matrix matrix) {
 
    assert isAffine() : this;
    return true;
}
/**
 * Returns {@code true} if this matrix is an identity matrix using the provided tolerance.
 * @since 2.3.1
 */
public final boolean isIdentity(double tolerance) {
    return isIdentity(this, tolerance);
}
/**
 * Returns {@code true} if this matrix is an identity matrix using the provided tolerance.
 * @since 2.3.1
 */
public final static boolean isIdentity(final XMatrix matrix,double tolerance) {
    tolerance=Math.abs(tolerance);
    final int numRow = matrix.getNumRow();
    final int numCol = matrix.getNumCol();
    if (numRow != numCol) {
        return false;
    }
    for (int j=0; j<numRow; j++) {
        for (int i=0; i<numCol; i++) {
            if (Math.abs(matrix.getElement(j,i)- (i==j ? 1 : 0))>tolerance) {
                return false;
            }
        }
    }
    assert matrix.isAffine() : matrix;
    return true;
}
/**
 * {@inheritDoc}
 */
public final void multiply(final Matrix matrix) {