public boolean isIdentity() {

		for (int x = 0; x < sizeX; ++x) {
			for (int y = 0; y < sizeY; ++y) {

				if (x == y) {
					if ( Math.abs( values[ ( y * sizeX ) + x  ] - 1.0f ) > 0.1f ) {						
						return false;
					}
				} else {
					if (!Utils.eqFloat(0.0f, values[ ( y * sizeX ) + x ]))
						return false;
				}
			}
		}

		return true;
	}