def calc_slope(self, dem):
"""Calculate the slope
Arguments:
dem {numpy} -- dem array
"""
return gradient_d8(dem, self.dx, self.dy, aspect_rad=True)
def test_gradient_d8_flat(self):
""" Test for the gradient_d8 for flat """
# test south slope and aspect
dem = np.ones((10, 10))
py_slope, asp = gradient.gradient_d8(dem, self.dx, self.dy)
ipw_a = gradient.aspect_to_ipw_radians(asp)
self.assertTrue(np.all(py_slope == 0))
self.assertTrue(np.all(asp == 180))
self.assertTrue(np.all(ipw_a == 0))
def test_gradient_d8_ne(self):
""" Test for the gradient_d8 for ne """
# test northeast slope and aspect
dem = self.gen_dem_ne()
py_slope, asp = gradient.gradient_d8(dem, self.dx, self.dy)
ipw_a = gradient.aspect_to_ipw_radians(asp)
self.assertTrue(np.all(py_slope == self.slope_val))
self.assertTrue(np.all(asp == 45))
self.assertTrue(np.all(ipw_a == (np.pi / 2 + np.pi / 4)))
def test_gradient_d8_sw(self):
""" Test for the gradient_d8 for sw """
# test southwest slope and aspect
dem = self.gen_dem_sw()
py_slope, asp = gradient.gradient_d8(dem, self.dx, self.dy)
ipw_a = gradient.aspect_to_ipw_radians(asp)
self.assertTrue(np.all(py_slope == self.slope_val))
self.assertTrue(np.all(asp == 225))
self.assertTrue(np.all(ipw_a == -np.pi / 4))
def test_gradient_d8_south(self):
""" Test for the gradient_d8 for south """
# test south slope and aspect
dem = np.flipud(np.tile(range(10), (10, 1)).transpose())
py_slope, asp = gradient.gradient_d8(dem, self.dx, self.dy)
ipw_a = gradient.aspect_to_ipw_radians(asp)
self.assertTrue(np.all(py_slope == np.pi / 4))
self.assertTrue(np.all(asp == 180))
self.assertTrue(np.all(ipw_a == 0))
def test_gradient_d8_east(self):
""" Test for the gradient_d8 for east """
# test east slope and aspect
dem = np.fliplr(np.tile(range(10), (10, 1)))
py_slope, asp = gradient.gradient_d8(dem, self.dx, self.dy)
ipw_a = gradient.aspect_to_ipw_radians(asp)
self.assertTrue(np.all(py_slope == np.pi / 4))
self.assertTrue(np.all(asp == 90))
self.assertTrue(np.all(ipw_a == np.pi / 2))