Changes in 1.2.x

* In :meth:`~matplotlib.axes.Axes.contourf`, the handling of the *extend*

kwarg has changed. Formerly, the extended ranges were mapped

after to 0, 1 after being normed, so that they always corresponded

*capthick*.

* Transform subclassing behaviour is now subtly changed. If your transform

``transform_non_affine`` method, rather than the generic ``transform`` method.

Previously transforms would define ``transform`` and then copy the

method into ``transform_non_affine``:

class MyTransform(mtrans.Transform):

def transform(self, xy):

...

transform_non_affine = transform

This approach will no longer function correctly and should be changed to:

class MyTransform(mtrans.Transform):

def transform_non_affine(self, xy):

...

* Artists no longer have ``x_isdata`` or ``y_isdata`` attributes; instead

any artist's transform can be interrogated with

``artist_instance.get_transform().contains_branch(ax.transData)``

* Lines added to an axes now take into account their transform when updating the

data and view limits. This means transforms can now be used as a pre-transform.

For instance:

>>> import matplotlib.pyplot as plt

>>> import matplotlib.transforms as mtrans

>>> ax = plt.axes()

>>> ax.plot(range(10), transform=mtrans.Affine2D().scale(10) + ax.transData)

>>> print(ax.viewLim)

Bbox('array([[ 0., 0.],\n [ 90., 90.]])')

* One can now easily get a transform which goes from one transform's coordinate system

to another, in an optimized way, using the new subtract method on a transform. For instance,

to go from data coordinates to axes coordinates::

* ``twinx`` and ``twiny`` now returns an instance of SubplotBase if

parent axes is an instance of SubplotBase.

Changes in 1.1.x