matplotlib
diff --git a/‎examples/subplots_axes_and_figures/secondary_axis.py
Copy file name to clipboardExpand all lines: examples/subplots_axes_and_figures/secondary_axis.py
+4-19Lines changed: 4 additions & 19 deletions b/‎examples/subplots_axes_and_figures/secondary_axis.py
Copy file name to clipboardExpand all lines: examples/subplots_axes_and_figures/secondary_axis.py
+4-19Lines changed: 4 additions & 19 deletions
diff --git a/‎lib/matplotlib/scale.py
Copy file name to clipboardExpand all lines: lib/matplotlib/scale.py
+2-4Lines changed: 2 additions & 4 deletions b/‎lib/matplotlib/scale.py
Copy file name to clipboardExpand all lines: lib/matplotlib/scale.py
+2-4Lines changed: 2 additions & 4 deletions
diff --git a/‎lib/mpl_toolkits/mplot3d/axes3d.py
Copy file name to clipboardExpand all lines: lib/mpl_toolkits/mplot3d/axes3d.py
+1-1Lines changed: 1 addition & 1 deletion b/‎lib/mpl_toolkits/mplot3d/axes3d.py
Copy file name to clipboardExpand all lines: lib/mpl_toolkits/mplot3d/axes3d.py
+1-1Lines changed: 1 addition & 1 deletion
@@ -6,9 +6,9 @@
 Sometimes we want as secondary axis on a plot, for instance to convert
 radians to degrees on the same plot.  We can do this by making a child
 axes with only one axis visible via `.Axes.axes.secondary_xaxis` and
-`.Axes.axes.secondary_yaxis`.
-
-If we want to label the top of the axes:
+`.Axes.axes.secondary_yaxis`.  This secondary axis can have a different scale
+than the main axis by providing both a forward and an inverse conversion
+function in a tuple to the ``functions`` kwarg:
 """
 
 import matplotlib.pyplot as plt
@@ -26,22 +26,6 @@
 ax.set_xlabel('angle [degrees]')
 ax.set_ylabel('signal')
 ax.set_title('Sine wave')
-secax = ax.secondary_xaxis('top')
-plt.show()
-
-###########################################################################
-# However, its often useful to label the secondary axis with something
-# other than the labels in the main axis. In that case we need to provide
-# both a forward and an inverse conversion function in a tuple
-# to the ``functions`` kwarg:
-
-fig, ax = plt.subplots(constrained_layout=True)
-x = np.arange(0, 360, 1)
-y = np.sin(2 * x * np.pi / 180)
-ax.plot(x, y)
-ax.set_xlabel('angle [degrees]')
-ax.set_ylabel('signal')
-ax.set_title('Sine wave')
 
 
 def deg2rad(x):
@@ -98,6 +82,7 @@ def inverse(x):
 
 xold = np.arange(0, 11, 0.2)
 # fake data set relating x co-ordinate to another data-derived co-ordinate.
+# xnew must be monotonic, so we sort...
 xnew = np.sort(10 * np.exp(-xold / 4) + np.random.randn(len(xold)) / 3)
 
 ax.plot(xold[3:], xnew[3:], label='Transform data')
 
@@ -163,8 +163,7 @@ def __init__(self, axis, functions):
 
         functions : (callable, callable)
             two-tuple of the forward and inverse functions for the scale.
-            The forward function must have an inverse and, for best behavior,
-            be monotonic.
+            The forward function must be monotonic
 
             Both functions must have the signature::
 
@@ -426,8 +425,7 @@ def __init__(self, axis, functions, base=10):
 
         functions : (callable, callable)
             two-tuple of the forward and inverse functions for the scale.
-            The forward function must have an inverse and, for best behavior,
-            be monotonic.
+            The forward function must be monotonic.
 
             Both functions must have the signature::
 
 
@@ -829,7 +829,7 @@ def set_yscale(self, value, **kwargs):
 
     def set_zscale(self, value, **kwargs):
         """
-        Set the x-axis scale.
+        Set the z-axis scale.
 
         Parameters
         ----------