Cleanup: use is not instead of not ... is, etc.

anntzer · anntzer · commit c1206f476e07 · 2017-01-23T14:21:14.000-08:00
diff --git a/lib/matplotlib/axes/_axes.py b/lib/matplotlib/axes/_axes.py
@@ -3998,16 +3998,16 @@ def scatter(self, x, y, s=None, c=None, marker=None, cmap=None, norm=None,
         else:
             colors = None  # use cmap, norm after collection is created
 
-        # Anything in maskargs will be unchanged unless it is the same length
-        # as x:
-        maskargs = x, y, s, c, colors, edgecolors, linewidths
+        # `delete_masked_points` only modifies arguments of the same length as
+        # `x`.
         x, y, s, c, colors, edgecolors, linewidths =\
-            cbook.delete_masked_points(*maskargs)
+            cbook.delete_masked_points(
+                x, y, s, c, colors, edgecolors, linewidths)
 
         scales = s   # Renamed for readability below.
 
         # to be API compatible
-        if marker is None and not (verts is None):
+        if marker is None and verts is not None:
             marker = (verts, 0)
             verts = None
 
diff --git a/lib/matplotlib/backends/backend_pdf.py b/lib/matplotlib/backends/backend_pdf.py
@@ -2336,27 +2336,11 @@ def delta(self, other):
         cmds = []
         fill_performed = False
         for params, cmd in self.commands:
-            different = False
-            for p in params:
-                ours = getattr(self, p)
-                theirs = getattr(other, p)
-                try:
-                    if (ours is None or theirs is None):
-                        different = bool(not(ours is theirs))
-                    else:
-                        different = bool(ours != theirs)
-                except ValueError:
-                    ours = np.asarray(ours)
-                    theirs = np.asarray(theirs)
-                    different = (ours.shape != theirs.shape or
-                                 np.any(ours != theirs))
-                if different:
-                    break
-
-            # Need to update hatching if we also updated fillcolor
-            if params == ('_hatch',) and fill_performed:
-                different = True
-
+            different = (
+                any(not np.array_equal(getattr(self, p), getattr(other, p))
+                    for p in params)
+                # Need to update hatching if we also updated fillcolor
+                or (params == ('_hatch',) and fill_performed))
             if different:
                 if params == ('_fillcolor',):
                     fill_performed = True
diff --git a/lib/matplotlib/cbook/__init__.py b/lib/matplotlib/cbook/__init__.py
@@ -1505,15 +1505,12 @@ def __iter__(self):
         The iterator is invalid if interleaved with calls to join().
         """
         self.clean()
-
-        class Token:
-            pass
-        token = Token()
+        token = object()
 
         # Mark each group as we come across if by appending a token,
         # and don't yield it twice
         for group in six.itervalues(self._mapping):
-            if not group[-1] is token:
+            if group[-1] is not token:
                 yield [x() for x in group]
                 group.append(token)
 
diff --git a/lib/matplotlib/mlab.py b/lib/matplotlib/mlab.py
@@ -3348,7 +3348,7 @@ def griddata(x, y, z, xi, yi, interp='nn'):
 
     # Remove masked points.
     mask = np.ma.getmask(z)
-    if not (mask is np.ma.nomask):
+    if mask is not np.ma.nomask:
         x = x.compress(~mask)
         y = y.compress(~mask)
         z = z.compressed()
