Test: added expanded x-axis and no tolerance

Author: Luiskitsu

src/diffpy/morph/morphs/morphsqueeze.py

@@ -26,7 +26,6 @@ class MorphSqueeze(Morph):
     parnames = ["squeeze"]
 
     def morph(self, x_morph, y_morph, x_target, y_target):
-
         Morph.morph(self, x_morph, y_morph, x_target, y_target)
         if self.squeeze is None or np.allclose(self.squeeze, 0):
             self.x_morph_out = self.x_morph_in
@@ -37,12 +36,8 @@ def morph(self, x_morph, y_morph, x_target, y_target):
         x_squeezed = self.x_morph_in + squeeze_polynomial(self.x_morph_in)
 
         self.y_morph_out = interp1d(
-            x_squeezed,
-            self.y_morph_in,
-            kind="cubic",
-            bounds_error=False,
-            fill_value="extrapolate",
+            x_squeezed, self.y_morph_in, kind="cubic", bounds_error=False
         )(self.x_morph_in)
-        self.x_morph_out = self.x_morph_in
 
+        self.x_morph_out = self.x_morph_in
         return self.xyallout

tests/test_morphsqueeze.py

@@ -14,26 +14,31 @@
         # Positive cubic squeeze coefficients
         [0.2, 0.01, 0.001, 0.001],
         # Positive and negative cubic squeeze coefficients
-        [0.2, -0.01, 0.001, -0.001],
+        [0.2, -0.01, 0.002, -0.001],
         # Quadratic squeeze coefficients
-        [-0.2, 0.005, -0.003],
+        [-0.2, 0.005, -0.007],
         # Linear squeeze coefficients
         [0.1, 0.3],
         # 4th order squeeze coefficients
-        [0.2, -0.01, 0.001, -0.001, 0.0001],
-        # Testing zeros
+        [0.2, -0.01, 0.001, -0.001, 0.0004],
+        # Zeros and non-zeros, expect 0 + a1x + 0 + a3x**3
+        [0, 0.03, 0, -0.001],
+        # Testing zeros, expect no squeezing
         [0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
     ],
 )
 def test_morphsqueeze(squeeze_coeffs):
-
-    x_target = np.linspace(0, 10, 1000)
+    x_target = np.linspace(0, 10, 1001)
     y_target = np.sin(x_target)
 
+    x_make = np.linspace(-3, 13, 1601)
+    lower_idx = np.where(x_make == 0.0)[0][0]
+    upper_idx = np.where(x_make == 10.0)[0][0]
+
     squeeze_polynomial = Polynomial(squeeze_coeffs)
-    x_squeezed = x_target + squeeze_polynomial(x_target)
+    x_squeezed = x_make + squeeze_polynomial(x_make)
 
-    x_morph = x_target.copy()
+    x_morph = x_make.copy()
     y_morph = np.sin(x_squeezed)
 
     morph = MorphSqueeze()
@@ -42,7 +47,14 @@ def test_morphsqueeze(squeeze_coeffs):
     x_actual, y_actual, x_expected, y_expected = morph(
         x_morph, y_morph, x_target, y_target
     )
-
-    # Check that the morphed (actual) data matches the expected data
-    # Including tolerance error because of extrapolation error
-    assert np.allclose(y_actual, y_expected, atol=0.1)
+    y_actual = y_actual[lower_idx : upper_idx + 1]
+    assert np.allclose(y_actual, y_expected)
+
+    # Plotting code used for figures in PR comments
+    # https://github.com/diffpy/diffpy.morph/pull/180
+    # plt.figure()
+    # plt.scatter(x_expected, y_expected, color='black', label='Expected')
+    # plt.plot(x_morph, y_morph, color='purple', label='morph')
+    # plt.plot(x_actual, y_actual, '--', color='gold', label='Actual')
+    # plt.legend()
+    # plt.show()