1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
|
.. _environment-variables:
.. redirect-from:: /faq/installing_faq
.. redirect-from:: /users/faq/installing_faq
.. redirect-from:: /users/installing/environment_variables_faq
=====================
Environment variables
=====================
.. envvar:: HOME
The user's home directory. On Linux, :envvar:`~ <HOME>` is shorthand for :envvar:`HOME`.
.. envvar:: MPLBACKEND
This optional variable can be set to choose the Matplotlib backend. See
:ref:`what-is-a-backend`.
.. envvar:: MPLCONFIGDIR
This is the directory used to store user customizations to
Matplotlib, as well as some caches to improve performance. If
:envvar:`MPLCONFIGDIR` is not defined, :file:`{HOME}/.config/matplotlib`
and :file:`{HOME}/.cache/matplotlib` are used on Linux, and
:file:`{HOME}/.matplotlib` on other platforms, if they are
writable. Otherwise, the Python standard library's `tempfile.gettempdir` is
used to find a base directory in which the :file:`matplotlib` subdirectory is
created.
.. envvar:: PATH
The list of directories searched to find executable programs.
.. envvar:: PYTHONPATH
The list of directories that are added to Python's standard search list when
importing packages and modules.
.. envvar:: QT_API
The Python Qt wrapper to prefer when using Qt-based backends. See :ref:`the
entry in the usage guide <QT_bindings>` for more information.
.. _setting-linux-macos-environment-variables:
Setting environment variables in Linux and macOS
================================================
To list the current value of :envvar:`PYTHONPATH`, which may be empty, try::
echo $PYTHONPATH
The procedure for setting environment variables in depends on what your default
shell is. Common shells include :program:`bash` and :program:`csh`. You
should be able to determine which by running at the command prompt::
echo $SHELL
To create a new environment variable::
export PYTHONPATH=~/Python # bash/ksh
setenv PYTHONPATH ~/Python # csh/tcsh
To prepend to an existing environment variable::
export PATH=~/bin:${PATH} # bash/ksh
setenv PATH ~/bin:${PATH} # csh/tcsh
The search order may be important to you, do you want :file:`~/bin` to be
searched first or last? To append to an existing environment variable::
export PATH=${PATH}:~/bin # bash/ksh
setenv PATH ${PATH}:~/bin # csh/tcsh
To make your changes available in the future, add the commands to your
:file:`~/.bashrc` or :file:`~/.cshrc` file.
.. _setting-windows-environment-variables:
Setting environment variables in Windows
========================================
Open the :program:`Control Panel` (:menuselection:`Start --> Control Panel`),
start the :program:`System` program. Click the :guilabel:`Advanced` tab
and select the :guilabel:`Environment Variables` button. You can edit or add to
the :guilabel:`User Variables`.
|
