public void testSign() {
		for (double x = -80D; x < 80D; x++) {
			for (double y = -80D; y < 80D; y++) {
				int s = this.cm.evaluateSlopeSign(0, x, y, 1D);
				System.out.print(s < 0 ? "<" : s > 0 ? ">" : " ");
				int sY = this.cm.evaluateSlopeSign(1, x, y, 1D);
				System.out.print(sY < 0 ? "v" : sY > 0 ? "^" : " ");
				double v = this.cm.evaluate(x, y, 1D);
				System.out.print(Math.abs(v) <= 1.e-1D ? " " : v < 0 ? "¤"
						: " ");
			}
			System.out.println();
		}
		assertTrue(true);
	}