.. include:: prev_api_changes/api_changes_3.1.1.rst

.. include:: prev_api_changes/api_changes_3.1.0.rst

Deprecations

Support in `matplotlib.testing` for nose-based tests is deprecated (a

deprecation is emitted if using e.g. the decorators from that module while

both 1) matplotlib's conftests have not been called and 2) nose is in

``sys.modules``).

``testing.is_called_from_pytest`` is deprecated.

During the deprecation period, to force the generation of nose base tests,

import nose first.

Removals

The following API elements have been removed:

- ``backend_gtk3.PIXELS_PER_INCH``,

- ``backend_pgf.re_escapetext``, ``backend_pgf.re_mathdefault``.

``axes3d.unit_bbox`` is deprecated (use ``Bbox.unit`` instead).