public static void testAngleVector2dVector2d() {
Vector2d testVec1 = new Vector2d(-9.37, 5.892);
Vector2d testVec2 = new Vector2d();
// angle(v, v) should give 0
double angle = testVec1.angle(testVec1);
assertEquals(0, angle, TestUtil.MANY_OPS_AROUND_ZERO_PRECISION_DOUBLE);
// angle(v, -v) should give Math.PI
testVec1.negate(testVec2);
angle = testVec1.angle(testVec2);
assertEquals(java.lang.Math.PI, angle, TestUtil.MANY_OPS_AROUND_ZERO_PRECISION_DOUBLE);
}
