Lines Matching +full:python +full:- +full:version
2 .. _tut-venv:
11 Python applications will often use packages and modules that don't
13 need a specific version of a library, because the application may
15 written using an obsolete version of the library's interface.
17 This means it may not be possible for one Python installation to meet
18 the requirements of every application. If application A needs version
19 1.0 of a particular module but application B needs version 2.0, then
20 the requirements are in conflict and installing either version 1.0 or 2.0
24 self-contained directory tree that contains a Python installation for a
25 particular version of Python, plus a number of additional packages.
29 application A can have its own virtual environment with version 1.0
30 installed while application B has another virtual environment with version 2.0.
31 If application B requires a library be upgraded to version 3.0, this will
39 :mod:`venv`. :mod:`venv` will usually install the most recent version of
40 Python that you have available. If you have multiple versions of Python on your
41 system, you can select a specific Python version by running ``python3`` or
42 whichever version you want.
47 python3 -m venv tutorial-env
49 This will create the ``tutorial-env`` directory if it doesn't exist,
50 and also create directories inside it containing a copy of the Python
63 tutorial-env\Scripts\activate.bat
67 source tutorial-env/bin/activate
76 ``python`` will get you that particular version and installation of Python.
79 .. code-block:: bash
81 $ source ~/envs/tutorial-env/bin/activate
82 (tutorial-env) $ python
83 Python 3.5.1 (default, May 6 2016, 10:59:36)
88 '~/envs/tutorial-env/lib/python3.5/site-packages']
96 :program:`pip`. By default ``pip`` will install packages from the Python
97 Package Index, <https://pypi.org>. You can browse the Python
101 "freeze", etc. (Consult the :ref:`installing-index` guide for
104 You can install the latest version of a package by specifying a package's name:
106 .. code-block:: bash
108 (tutorial-env) $ python -m pip install novas
110 Downloading novas-3.1.1.3.tar.gz (136kB)
113 Successfully installed novas-3.1.1.3
115 You can also install a specific version of a package by giving the
116 package name followed by ``==`` and the version number:
118 .. code-block:: bash
120 (tutorial-env) $ python -m pip install requests==2.6.0
122 Using cached requests-2.6.0-py2.py3-none-any.whl
124 Successfully installed requests-2.6.0
126 If you re-run this command, ``pip`` will notice that the requested
127 version is already installed and do nothing. You can supply a
128 different version number to get that version, or you can run ``pip
129 install --upgrade`` to upgrade the package to the latest version:
131 .. code-block:: bash
133 (tutorial-env) $ python -m pip install --upgrade requests
137 Uninstalling requests-2.6.0:
138 Successfully uninstalled requests-2.6.0
139 Successfully installed requests-2.7.0
146 .. code-block:: bash
148 (tutorial-env) $ pip show requests
149 ---
150 Metadata-Version: 2.0
152 Version: 2.7.0
153 Summary: Python HTTP for Humans.
154 Home-page: http://python-requests.org
156 Author-email: me@kennethreitz.com
158 Location: /Users/akuchling/envs/tutorial-env/lib/python3.4/site-packages
164 .. code-block:: bash
166 (tutorial-env) $ pip list
177 .. code-block:: bash
179 (tutorial-env) $ pip freeze > requirements.txt
180 (tutorial-env) $ cat requirements.txt
185 The ``requirements.txt`` can then be committed to version control and
187 necessary packages with ``install -r``:
189 .. code-block:: bash
191 (tutorial-env) $ python -m pip install -r requirements.txt
192 Collecting novas==3.1.1.3 (from -r requirements.txt (line 1))
194 Collecting numpy==1.9.2 (from -r requirements.txt (line 2))
196 Collecting requests==2.7.0 (from -r requirements.txt (line 3))
200 Successfully installed novas-3.1.1.3 numpy-1.9.2 requests-2.7.0
202 ``pip`` has many more options. Consult the :ref:`installing-index`
204 a package and want to make it available on the Python Package Index,
205 consult the :ref:`distributing-index` guide.