Ensure that arguments to quiver() are not matrices.

anntzer · anntzer · commit 80bf85bf13d6 · 2019-01-03T14:26:27.000+01:00
diff --git a/lib/matplotlib/cbook/__init__.py b/lib/matplotlib/cbook/__init__.py
@@ -2178,3 +2178,13 @@ def _check_and_log_subprocess(command, logger, **kwargs):
             .format(command, exc.output.decode('utf-8')))
     logger.debug(report)
     return report
+
+
+def _check_not_matrix(**kwargs):
+    """
+    If any value in *kwargs* is a `np.matrix`, raise a TypeError with the key
+    name in its message.
+    """
+    for k, v in kwargs.items():
+        if isinstance(v, np.matrix):
+            raise TypeError(f"Argument {k!r} cannot be a np.matrix")
diff --git a/lib/matplotlib/quiver.py b/lib/matplotlib/quiver.py
@@ -381,7 +381,7 @@ def contains(self, mouseevent):
 # arguments for doing colored vector plots.  Pulling it out here
 # allows both Quiver and Barbs to use it
 def _parse_args(*args):
-    X, Y, U, V, C = [None] * 5
+    X = Y = U = V = C = None
     args = list(args)
 
     # The use of atleast_1d allows for handling scalar arguments while also
@@ -390,6 +390,7 @@ def _parse_args(*args):
         C = np.atleast_1d(args.pop(-1))
     V = np.atleast_1d(args.pop(-1))
     U = np.atleast_1d(args.pop(-1))
+    cbook._check_not_matrix(U=U, V=V, C=C)
     if U.ndim == 1:
         nr, nc = 1, U.shape[0]
     else:
diff --git a/tutorials/introductory/usage.py b/tutorials/introductory/usage.py
@@ -137,9 +137,9 @@
 # For example, to convert a `pandas.DataFrame` ::
 #
 #   a = pandas.DataFrame(np.random.rand(4,5), columns = list('abcde'))
-#   a_asndarray = a.values
+#   a_asarray = a.values
 #
-# and to covert a `np.matrix` ::
+# and to convert a `np.matrix` ::
 #
 #   b = np.matrix([[1,2],[3,4]])
 #   b_asarray = np.asarray(b)

Original file line number	Diff line number	Diff line change
`@@ -137,9 +137,9 @@`
`137`	`137`	# For example, to convert a `pandas.DataFrame` ::
`138`	`138`	`#`
`139`	`139`	`# a = pandas.DataFrame(np.random.rand(4,5), columns = list('abcde'))`
`140`		`-# a_asndarray = a.values`
	`140`	`+# a_asarray = a.values`
`141`	`141`	`#`
`142`		-# and to covert a `np.matrix` ::
	`142`	+# and to convert a `np.matrix` ::
`143`	`143`	`#`
`144`	`144`	`# b = np.matrix([[1,2],[3,4]])`
`145`	`145`	`# b_asarray = np.asarray(b)`