@Test
    public void testCopysign() {
        assertEquals(-3.85186e-34, FastMath.copysign(-3.85186e-34f, -1.0f), 0.01f);
        assertEquals(0.0f, FastMath.copysign(0.0f, Float.NaN), 0.0f);
        assertEquals(Float.NaN, FastMath.copysign(Float.NaN, 1.0f), 0.0f);
        assertEquals(0.0f, FastMath.copysign(-0.0f, -1.0f), 0.0f);
        assertEquals(0.0f, FastMath.copysign(-0.0f, 0.0f), 0.0f);
        assertEquals(-1.0f, FastMath.copysign(1.0f, -3.0f), 0.0f);
    }
Verifies that algorithms in {@link FastMath} are working correctly.

@author Kirill Vainer
jme3-core/src/test/java/com/jme3/math/FastMathTest.java