def test_randomly_rough(self):
surface = fourier_synthesis((511, 511), (1., 1.), 0.8, rms_height=1)
self.assertTrue(surface.is_uniform)
cut = Topography(surface[:64, :64], physical_sizes=(64., 64.))
self.assertTrue(cut.is_uniform)
untilt1 = cut.detrend(detrend_mode='height')
untilt2 = cut.detrend(detrend_mode='slope')
self.assertTrue(untilt1.is_uniform)
self.assertTrue(untilt2.is_uniform)
self.assertTrue(untilt1.rms_height_from_area() < untilt2.rms_height_from_area())
self.assertTrue(untilt1.rms_gradient() > untilt2.rms_gradient())
def test_checkerboard_detrend_with_no_subdivisions(self):
r = 32
x, y = np.mgrid[:r, :r]
h = 1.3 * x - 0.3 * y + 0.02 * x * x + 0.03 * y * y - 0.013 * x * y
t = Topography(h, (1, 1), periodic=False)
# This should be the same as a detrend with detrend_mode='height'
ut1 = t.checkerboard_detrend((1, 1))
ut2 = t.detrend().heights()
np.testing.assert_allclose(ut1, ut2)
def test_positions_and_heights():
X = np.arange(3).reshape(1, 3)
Y = np.arange(4).reshape(4, 1)
h = X + Y
t = Topography(h, (8, 6))
assert t.nb_grid_pts == (4, 3)
assert_array_equal(t.heights(), h)
X2, Y2, h2 = t.positions_and_heights()
assert_array_equal(X2, [
(0, 0, 0),
(2, 2, 2),
(4, 4, 4),
(6, 6, 6),
])
assert_array_equal(Y2, [
(0, 2, 4),
(0, 2, 4),
(0, 2, 4),
(0, 2, 4),
])
assert_array_equal(h2, [(0, 1, 2), (1, 2, 3), (2, 3, 4), (3, 4, 5)])
#
# After detrending, the position and heights should have again
# just 3 arrays and the third array should be the same as .heights()
#
dt = t.detrend(detrend_mode='slope')
np.testing.assert_allclose(dt.heights(), [(0, 0, 0), (0, 0, 0), (0, 0, 0),
(0, 0, 0)],
atol=1e-15)
X2, Y2, h2 = dt.positions_and_heights()
assert h2.shape == (4, 3)
assert_array_equal(X2, [
(0, 0, 0),
(2, 2, 2),
(4, 4, 4),
(6, 6, 6),
])
assert_array_equal(Y2, [
(0, 2, 4),
(0, 2, 4),
(0, 2, 4),
(0, 2, 4),
])
np.testing.assert_allclose(h2, [(0, 0, 0), (0, 0, 0), (0, 0, 0),
(0, 0, 0)],
atol=1e-15)
def test_smooth_curved(self):
a = 1.2
b = 2.5
c = 0.1
d = 0.2
e = 0.3
f = 5.5
x = np.arange(5).reshape((1, -1))
y = np.arange(6).reshape((-1, 1))
arr = f + x * a + y * b + x * x * c + y * y * d + x * y * e
sx, sy = 3, 2.5
nx, ny = arr.shape
surf = Topography(arr, physical_sizes=(sx, sy))
surf = surf.detrend(detrend_mode='curvature')
self.assertTrue(surf.is_uniform)
self.assertAlmostEqual(surf.coeffs[0], b * nx)
self.assertAlmostEqual(surf.coeffs[1], a * ny)
self.assertAlmostEqual(surf.coeffs[2], d * (nx * nx))
self.assertAlmostEqual(surf.coeffs[3], c * (ny * ny))
self.assertAlmostEqual(surf.coeffs[4], e * (nx * ny))
self.assertAlmostEqual(surf.coeffs[5], f)
self.assertAlmostEqual(surf.rms_height_from_area(), 0.0)
self.assertAlmostEqual(surf.rms_gradient(), 0.0)
self.assertAlmostEqual(surf.rms_curvature_from_area(), 0.0)