test: writting better docstrings and comments

Author: Luiskitsu

src/diffpy/morph/morphs/morphsqueeze.py

@@ -9,9 +9,29 @@ class MorphSqueeze(Morph):
 
     Configuration Variables
     -----------------------
-    squeeze
-        list or array-like
-        Polynomial coefficients [a0, a1, ..., an] for the squeeze function.
+    squeeze : list
+        The polynomial coefficients [a0, a1, ..., an] for the squeeze function
+        where the polynomial would be of the form a0 + a1*x + a2*x^2 and so
+        on.  The order of the polynomial is determined by the length of the
+        list.
+
+    Example
+    -------
+    >>> import numpy as np
+    >>> from numpy.polynomial import Polynomial
+    >>> from diffpy.morph.morphs.morphsqueeze import MorphSqueeze
+
+    >>> x_morph = np.linspace(0, 10, 101)
+    >>> x_target = np.linspace(0, 10, 101)
+    >>> squeeze_coeff = [0.1, -0.01, 0.005]
+    >>> poly = Polynomial(squeeze_coeff)
+    >>> y_morph = np.sin(x_morph + poly(x_morph))
+    >>> y_target = np.sin(x_target)
+
+    >>> morph = MorphSqueeze()
+    >>> morph.squeeze = squeeze_coeff
+    >>> x_morph_out, y_morph_out, x_target_out, y_target_out = morph(
+    ...     x_morph, y_morph, x_target, y_target)
     """
 
     # Define input output types
@@ -23,6 +43,7 @@ class MorphSqueeze(Morph):
     parnames = ["squeeze"]
 
     def morph(self, x_morph, y_morph, x_target, y_target):
+        """Apply a polynomial to squeeze the morph function"""
         Morph.morph(self, x_morph, y_morph, x_target, y_target)
 
         return self.xyallout

tests/test_morphsqueeze.py

@@ -25,17 +25,17 @@
 ]
 morph_target_grids = [
     # UCs from issue 181: https://github.com/diffpy/diffpy.morph/issues/181
-    # UC2: Same grid
+    # UC2: Same range and same grid density
     (np.linspace(0, 10, 101), np.linspace(0, 10, 101)),
-    # UC4: Target extends beyond morph
+    # UC4: Target range wider than morph, same grid density
     (np.linspace(0, 10, 101), np.linspace(-2, 20, 221)),
-    # UC6: Target extends beyond morph; morph coarser
+    # UC6: Target range wider than morph, finer target grid density
     (np.linspace(0, 10, 101), np.linspace(-2, 20, 421)),
-    # UC8: Target extends beyond morph; target coarser
+    # UC8: Target range wider than morph, finer morph grid density
     (np.linspace(0, 10, 401), np.linspace(-2, 20, 200)),
-    # UC10: morph starts earlier than target
+    # UC10: Morph range starts and ends earlier than target, same grid density
     (np.linspace(-2, 10, 121), np.linspace(0, 20, 201)),
-    # UC12: morph extends beyond target
+    # UC12: Morph range wider than target, same grid density
     (np.linspace(-2, 20, 221), np.linspace(0, 10, 101)),
 ]