Merge pull request #17 from yucongalicechen/distances

Tests for setting distances for each grid point

Author: sbillinge

src/diffpy/labpdfproc/functions.py

@@ -59,7 +59,6 @@ def set_distances_at_angle(self, angle):
             self.secondary_distances.append(secondary)
 
     def set_muls_at_angle(self, angle):
-        # newly added docstring
         """
         compute muls = exp(-mu*distance) for a given angle
 
@@ -129,7 +128,7 @@ def _get_entry_exit_coordinates(self, coordinate, angle):
             xexit_root1, xexit_root2 = np.roots((1 + a**2, 2 * a * b, b**2 - self.radius**2))
             yexit_root1 = a * xexit_root1 + b
             yexit_root2 = a * xexit_root2 + b
-            if yexit_root2 >= ygrid:  # We pick the point above
+            if yexit_root2 >= yexit_root1:  # We pick the point above
                 exit_point = (xexit_root2, yexit_root2)
             else:
                 exit_point = (xexit_root1, yexit_root1)

src/diffpy/labpdfproc/tests/test_functions.py

@@ -16,3 +16,23 @@ def test_get_grid_points(inputs, expected):
     expected_grid_sorted = sorted(expected_grid)
     for actual_point, expected_point in zip(actual_grid_sorted, expected_grid_sorted):
         assert actual_point == pytest.approx(expected_point, rel=1e-4, abs=1e-6)
+
+
+params2 = [
+    ([1, 3, 1, 45], [0, 1.4142135, 1.4142135, 2, 2]),
+    ([1, 3, 1, 90], [0, 0, 2, 2, 2]),
+    ([1, 3, 1, 120], [0, 0, 2, 3, 1.73205]),
+    ([1, 4, 1, 30], [2.057347, 2.044451, 1.621801, 1.813330]),
+    ([1, 4, 1, 90], [1.885618, 1.885618, 2.552285, 1.218951]),
+    ([1, 4, 1, 140], [1.139021, 2.200102, 2.744909, 1.451264]),
+]
+
+
+@pytest.mark.parametrize("inputs, expected", params2)
+def test_set_distances_at_angle(inputs, expected):
+    expected_distances = expected
+    actual_gs = Gridded_circle(radius=inputs[0], n_points_on_diameter=inputs[1], mu=inputs[2])
+    actual_gs.set_distances_at_angle(inputs[3])
+    actual_distances_sorted = sorted(actual_gs.distances)
+    expected_distances_sorted = sorted(expected_distances)
+    assert actual_distances_sorted == pytest.approx(expected_distances_sorted, rel=1e-4, abs=1e-6)