forked from AFPy/python-docs-fr
971 lines
33 KiB
Plaintext
971 lines
33 KiB
Plaintext
# SOME DESCRIPTIVE TITLE.
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# Copyright (C) 1990-2016, Python Software Foundation
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# This file is distributed under the same license as the Python package.
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# FIRST AUTHOR <EMAIL@ADDRESS>, YEAR.
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#
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#, fuzzy
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msgid ""
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msgstr ""
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"Project-Id-Version: Python 2.7\n"
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"Report-Msgid-Bugs-To: \n"
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"POT-Creation-Date: 2016-10-30 10:44+0100\n"
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"PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
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"Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
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"Language-Team: LANGUAGE <LL@li.org>\n"
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"MIME-Version: 1.0\n"
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"Content-Type: text/plain; charset=UTF-8\n"
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"Content-Transfer-Encoding: 8bit\n"
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#: ../Doc/faq/library.rst:5
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msgid "Library and Extension FAQ"
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msgstr "FAQ sur la bibliothèque et les extension"
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#: ../Doc/faq/library.rst:12
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msgid "General Library Questions"
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msgstr "Questions générales sur la bibliothèque"
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#: ../Doc/faq/library.rst:15
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msgid "How do I find a module or application to perform task X?"
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msgstr ""
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"Comment puis-je trouver un module ou une application pour exécuter la tâche "
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"X?"
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#: ../Doc/faq/library.rst:17
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msgid ""
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"Check :ref:`the Library Reference <library-index>` to see if there's a "
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"relevant standard library module. (Eventually you'll learn what's in the "
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"standard library and will be able to skip this step.)"
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msgstr ""
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#: ../Doc/faq/library.rst:21
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msgid ""
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"For third-party packages, search the `Python Package Index <https://pypi."
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"python.org/pypi>`_ or try `Google <https://www.google.com>`_ or another Web "
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"search engine. Searching for \"Python\" plus a keyword or two for your "
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"topic of interest will usually find something helpful."
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msgstr ""
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#: ../Doc/faq/library.rst:28
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msgid "Where is the math.py (socket.py, regex.py, etc.) source file?"
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msgstr "Où se situe le fichier source math.py (socket.py, regex.py, etc.)?"
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#: ../Doc/faq/library.rst:30
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msgid ""
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"If you can't find a source file for a module it may be a built-in or "
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"dynamically loaded module implemented in C, C++ or other compiled language. "
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"In this case you may not have the source file or it may be something like :"
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"file:`mathmodule.c`, somewhere in a C source directory (not on the Python "
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"Path)."
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msgstr ""
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#: ../Doc/faq/library.rst:35
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msgid "There are (at least) three kinds of modules in Python:"
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msgstr "Il y a (au moins) trois types de modules dans Python"
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#: ../Doc/faq/library.rst:37
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msgid "modules written in Python (.py);"
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msgstr "modules écrits en Python (.py);"
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#: ../Doc/faq/library.rst:38
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msgid ""
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"modules written in C and dynamically loaded (.dll, .pyd, .so, .sl, etc);"
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msgstr ""
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"modules écrits en C et chargés dynamiquement (.dll, .pyd, .so, .sl, .etc);"
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#: ../Doc/faq/library.rst:39
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msgid ""
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"modules written in C and linked with the interpreter; to get a list of "
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"these, type::"
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msgstr ""
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#: ../Doc/faq/library.rst:47
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msgid "How do I make a Python script executable on Unix?"
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msgstr ""
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#: ../Doc/faq/library.rst:49
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msgid ""
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"You need to do two things: the script file's mode must be executable and the "
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"first line must begin with ``#!`` followed by the path of the Python "
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"interpreter."
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msgstr ""
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#: ../Doc/faq/library.rst:53
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msgid ""
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"The first is done by executing ``chmod +x scriptfile`` or perhaps ``chmod "
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"755 scriptfile``."
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msgstr ""
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#: ../Doc/faq/library.rst:56
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msgid ""
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"The second can be done in a number of ways. The most straightforward way is "
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"to write ::"
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msgstr ""
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#: ../Doc/faq/library.rst:61
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msgid ""
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"as the very first line of your file, using the pathname for where the Python "
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"interpreter is installed on your platform."
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msgstr ""
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#: ../Doc/faq/library.rst:64
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msgid ""
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"If you would like the script to be independent of where the Python "
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"interpreter lives, you can use the :program:`env` program. Almost all Unix "
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"variants support the following, assuming the Python interpreter is in a "
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"directory on the user's :envvar:`PATH`::"
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msgstr ""
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#: ../Doc/faq/library.rst:71
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msgid ""
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"*Don't* do this for CGI scripts. The :envvar:`PATH` variable for CGI "
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"scripts is often very minimal, so you need to use the actual absolute "
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"pathname of the interpreter."
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msgstr ""
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#: ../Doc/faq/library.rst:75
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msgid ""
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"Occasionally, a user's environment is so full that the :program:`/usr/bin/"
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"env` program fails; or there's no env program at all. In that case, you can "
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"try the following hack (due to Alex Rezinsky)::"
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msgstr ""
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#: ../Doc/faq/library.rst:84
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msgid ""
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"The minor disadvantage is that this defines the script's __doc__ string. "
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"However, you can fix that by adding ::"
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msgstr ""
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#: ../Doc/faq/library.rst:92
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msgid "Is there a curses/termcap package for Python?"
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msgstr ""
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#: ../Doc/faq/library.rst:96
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msgid ""
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"For Unix variants the standard Python source distribution comes with a "
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"curses module in the :source:`Modules` subdirectory, though it's not "
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"compiled by default. (Note that this is not available in the Windows "
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"distribution -- there is no curses module for Windows.)"
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msgstr ""
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#: ../Doc/faq/library.rst:101
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msgid ""
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"The :mod:`curses` module supports basic curses features as well as many "
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"additional functions from ncurses and SYSV curses such as colour, "
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"alternative character set support, pads, and mouse support. This means the "
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"module isn't compatible with operating systems that only have BSD curses, "
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"but there don't seem to be any currently maintained OSes that fall into this "
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"category."
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msgstr ""
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#: ../Doc/faq/library.rst:107
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msgid ""
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"For Windows: use `the consolelib module <http://effbot.org/zone/console-"
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"index.htm>`_."
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msgstr ""
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#: ../Doc/faq/library.rst:112
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msgid "Is there an equivalent to C's onexit() in Python?"
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msgstr ""
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#: ../Doc/faq/library.rst:114
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msgid ""
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"The :mod:`atexit` module provides a register function that is similar to "
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"C's :c:func:`onexit`."
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msgstr ""
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#: ../Doc/faq/library.rst:119
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msgid "Why don't my signal handlers work?"
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msgstr ""
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#: ../Doc/faq/library.rst:121
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msgid ""
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"The most common problem is that the signal handler is declared with the "
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"wrong argument list. It is called as ::"
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msgstr ""
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#: ../Doc/faq/library.rst:126
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msgid "so it should be declared with two arguments::"
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msgstr ""
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#: ../Doc/faq/library.rst:133
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msgid "Common tasks"
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msgstr ""
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#: ../Doc/faq/library.rst:136
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msgid "How do I test a Python program or component?"
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msgstr ""
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#: ../Doc/faq/library.rst:138
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msgid ""
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"Python comes with two testing frameworks. The :mod:`doctest` module finds "
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"examples in the docstrings for a module and runs them, comparing the output "
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"with the expected output given in the docstring."
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msgstr ""
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#: ../Doc/faq/library.rst:142
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msgid ""
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"The :mod:`unittest` module is a fancier testing framework modelled on Java "
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"and Smalltalk testing frameworks."
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msgstr ""
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#: ../Doc/faq/library.rst:145
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msgid ""
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"To make testing easier, you should use good modular design in your program. "
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"Your program should have almost all functionality encapsulated in either "
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"functions or class methods -- and this sometimes has the surprising and "
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"delightful effect of making the program run faster (because local variable "
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"accesses are faster than global accesses). Furthermore the program should "
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"avoid depending on mutating global variables, since this makes testing much "
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"more difficult to do."
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msgstr ""
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#: ../Doc/faq/library.rst:153
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msgid "The \"global main logic\" of your program may be as simple as ::"
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msgstr ""
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#: ../Doc/faq/library.rst:158
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msgid "at the bottom of the main module of your program."
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msgstr ""
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#: ../Doc/faq/library.rst:160
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msgid ""
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"Once your program is organized as a tractable collection of functions and "
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"class behaviours you should write test functions that exercise the "
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"behaviours. A test suite that automates a sequence of tests can be "
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"associated with each module. This sounds like a lot of work, but since "
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"Python is so terse and flexible it's surprisingly easy. You can make coding "
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"much more pleasant and fun by writing your test functions in parallel with "
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"the \"production code\", since this makes it easy to find bugs and even "
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"design flaws earlier."
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msgstr ""
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#: ../Doc/faq/library.rst:168
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msgid ""
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"\"Support modules\" that are not intended to be the main module of a program "
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"may include a self-test of the module. ::"
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msgstr ""
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#: ../Doc/faq/library.rst:174
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msgid ""
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"Even programs that interact with complex external interfaces may be tested "
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"when the external interfaces are unavailable by using \"fake\" interfaces "
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"implemented in Python."
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msgstr ""
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#: ../Doc/faq/library.rst:180
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msgid "How do I create documentation from doc strings?"
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msgstr ""
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#: ../Doc/faq/library.rst:182
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msgid ""
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"The :mod:`pydoc` module can create HTML from the doc strings in your Python "
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"source code. An alternative for creating API documentation purely from "
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"docstrings is `epydoc <http://epydoc.sourceforge.net/>`_. `Sphinx <http://"
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"sphinx-doc.org>`_ can also include docstring content."
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msgstr ""
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#: ../Doc/faq/library.rst:189
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msgid "How do I get a single keypress at a time?"
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msgstr ""
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#: ../Doc/faq/library.rst:191
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msgid ""
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"For Unix variants there are several solutions. It's straightforward to do "
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"this using curses, but curses is a fairly large module to learn. Here's a "
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"solution without curses::"
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msgstr ""
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#: ../Doc/faq/library.rst:216
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msgid ""
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"You need the :mod:`termios` and the :mod:`fcntl` module for any of this to "
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"work, and I've only tried it on Linux, though it should work elsewhere. In "
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"this code, characters are read and printed one at a time."
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msgstr ""
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#: ../Doc/faq/library.rst:220
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msgid ""
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":func:`termios.tcsetattr` turns off stdin's echoing and disables canonical "
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"mode. :func:`fcntl.fnctl` is used to obtain stdin's file descriptor flags "
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"and modify them for non-blocking mode. Since reading stdin when it is empty "
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"results in an :exc:`IOError`, this error is caught and ignored."
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msgstr ""
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#: ../Doc/faq/library.rst:227
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msgid "Threads"
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msgstr ""
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#: ../Doc/faq/library.rst:230
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msgid "How do I program using threads?"
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msgstr ""
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#: ../Doc/faq/library.rst:234
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msgid ""
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"Be sure to use the :mod:`threading` module and not the :mod:`thread` module. "
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"The :mod:`threading` module builds convenient abstractions on top of the low-"
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"level primitives provided by the :mod:`thread` module."
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msgstr ""
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#: ../Doc/faq/library.rst:238
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msgid ""
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"Aahz has a set of slides from his threading tutorial that are helpful; see "
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"http://www.pythoncraft.com/OSCON2001/."
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msgstr ""
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#: ../Doc/faq/library.rst:243
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msgid "None of my threads seem to run: why?"
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msgstr ""
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#: ../Doc/faq/library.rst:245
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msgid ""
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"As soon as the main thread exits, all threads are killed. Your main thread "
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"is running too quickly, giving the threads no time to do any work."
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msgstr ""
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#: ../Doc/faq/library.rst:248
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msgid ""
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"A simple fix is to add a sleep to the end of the program that's long enough "
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"for all the threads to finish::"
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msgstr ""
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#: ../Doc/faq/library.rst:262
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msgid ""
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"But now (on many platforms) the threads don't run in parallel, but appear to "
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"run sequentially, one at a time! The reason is that the OS thread scheduler "
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"doesn't start a new thread until the previous thread is blocked."
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msgstr ""
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#: ../Doc/faq/library.rst:266
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msgid "A simple fix is to add a tiny sleep to the start of the run function::"
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msgstr ""
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#: ../Doc/faq/library.rst:278
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msgid ""
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"Instead of trying to guess a good delay value for :func:`time.sleep`, it's "
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"better to use some kind of semaphore mechanism. One idea is to use the :mod:"
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"`Queue` module to create a queue object, let each thread append a token to "
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"the queue when it finishes, and let the main thread read as many tokens from "
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"the queue as there are threads."
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msgstr ""
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#: ../Doc/faq/library.rst:286
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msgid "How do I parcel out work among a bunch of worker threads?"
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msgstr ""
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#: ../Doc/faq/library.rst:288
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msgid ""
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"Use the :mod:`Queue` module to create a queue containing a list of jobs. "
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"The :class:`~Queue.Queue` class maintains a list of objects and has a ``."
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"put(obj)`` method that adds items to the queue and a ``.get()`` method to "
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"return them. The class will take care of the locking necessary to ensure "
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"that each job is handed out exactly once."
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msgstr ""
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#: ../Doc/faq/library.rst:294
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msgid "Here's a trivial example::"
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msgstr ""
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#: ../Doc/faq/library.rst:332
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msgid "When run, this will produce the following output:"
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msgstr ""
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#: ../Doc/faq/library.rst:350
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msgid ""
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"Consult the module's documentation for more details; the :class:`~Queue."
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"Queue` class provides a featureful interface."
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msgstr ""
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#: ../Doc/faq/library.rst:355
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msgid "What kinds of global value mutation are thread-safe?"
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msgstr ""
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#: ../Doc/faq/library.rst:357
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msgid ""
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"A :term:`global interpreter lock` (GIL) is used internally to ensure that "
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"only one thread runs in the Python VM at a time. In general, Python offers "
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"to switch among threads only between bytecode instructions; how frequently "
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"it switches can be set via :func:`sys.setcheckinterval`. Each bytecode "
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"instruction and therefore all the C implementation code reached from each "
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"instruction is therefore atomic from the point of view of a Python program."
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msgstr ""
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#: ../Doc/faq/library.rst:364
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msgid ""
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"In theory, this means an exact accounting requires an exact understanding of "
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"the PVM bytecode implementation. In practice, it means that operations on "
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"shared variables of built-in data types (ints, lists, dicts, etc) that "
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"\"look atomic\" really are."
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msgstr ""
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#: ../Doc/faq/library.rst:369
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msgid ""
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"For example, the following operations are all atomic (L, L1, L2 are lists, "
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"D, D1, D2 are dicts, x, y are objects, i, j are ints)::"
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msgstr ""
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#: ../Doc/faq/library.rst:384
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msgid "These aren't::"
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msgstr ""
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#: ../Doc/faq/library.rst:391
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msgid ""
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"Operations that replace other objects may invoke those other objects' :meth:"
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"`__del__` method when their reference count reaches zero, and that can "
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"affect things. This is especially true for the mass updates to dictionaries "
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"and lists. When in doubt, use a mutex!"
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msgstr ""
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#: ../Doc/faq/library.rst:398
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msgid "Can't we get rid of the Global Interpreter Lock?"
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msgstr ""
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#: ../Doc/faq/library.rst:403
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msgid ""
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"The :term:`global interpreter lock` (GIL) is often seen as a hindrance to "
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"Python's deployment on high-end multiprocessor server machines, because a "
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"multi-threaded Python program effectively only uses one CPU, due to the "
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"insistence that (almost) all Python code can only run while the GIL is held."
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msgstr ""
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#: ../Doc/faq/library.rst:408
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msgid ""
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"Back in the days of Python 1.5, Greg Stein actually implemented a "
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"comprehensive patch set (the \"free threading\" patches) that removed the "
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"GIL and replaced it with fine-grained locking. Unfortunately, even on "
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"Windows (where locks are very efficient) this ran ordinary Python code about "
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"twice as slow as the interpreter using the GIL. On Linux the performance "
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"loss was even worse because pthread locks aren't as efficient."
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msgstr ""
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#: ../Doc/faq/library.rst:415
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msgid ""
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"Since then, the idea of getting rid of the GIL has occasionally come up but "
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"nobody has found a way to deal with the expected slowdown, and users who "
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"don't use threads would not be happy if their code ran at half the speed. "
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"Greg's free threading patch set has not been kept up-to-date for later "
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"Python versions."
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msgstr ""
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#: ../Doc/faq/library.rst:420
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msgid ""
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"This doesn't mean that you can't make good use of Python on multi-CPU "
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"machines! You just have to be creative with dividing the work up between "
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"multiple *processes* rather than multiple *threads*. Judicious use of C "
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"extensions will also help; if you use a C extension to perform a time-"
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"consuming task, the extension can release the GIL while the thread of "
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"execution is in the C code and allow other threads to get some work done."
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msgstr ""
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#: ../Doc/faq/library.rst:427
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msgid ""
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"It has been suggested that the GIL should be a per-interpreter-state lock "
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"rather than truly global; interpreters then wouldn't be able to share "
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"objects. Unfortunately, this isn't likely to happen either. It would be a "
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"tremendous amount of work, because many object implementations currently "
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"have global state. For example, small integers and short strings are cached; "
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"these caches would have to be moved to the interpreter state. Other object "
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"types have their own free list; these free lists would have to be moved to "
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"the interpreter state. And so on."
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msgstr ""
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#: ../Doc/faq/library.rst:436
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msgid ""
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"And I doubt that it can even be done in finite time, because the same "
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"problem exists for 3rd party extensions. It is likely that 3rd party "
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"extensions are being written at a faster rate than you can convert them to "
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"store all their global state in the interpreter state."
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msgstr ""
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#: ../Doc/faq/library.rst:441
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msgid ""
|
|
"And finally, once you have multiple interpreters not sharing any state, what "
|
|
"have you gained over running each interpreter in a separate process?"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:446
|
|
msgid "Input and Output"
|
|
msgstr "Les entrées/sorties"
|
|
|
|
#: ../Doc/faq/library.rst:449
|
|
msgid "How do I delete a file? (And other file questions...)"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:451
|
|
msgid ""
|
|
"Use ``os.remove(filename)`` or ``os.unlink(filename)``; for documentation, "
|
|
"see the :mod:`os` module. The two functions are identical; :func:`unlink` "
|
|
"is simply the name of the Unix system call for this function."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:455
|
|
msgid ""
|
|
"To remove a directory, use :func:`os.rmdir`; use :func:`os.mkdir` to create "
|
|
"one. ``os.makedirs(path)`` will create any intermediate directories in "
|
|
"``path`` that don't exist. ``os.removedirs(path)`` will remove intermediate "
|
|
"directories as long as they're empty; if you want to delete an entire "
|
|
"directory tree and its contents, use :func:`shutil.rmtree`."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:461
|
|
msgid "To rename a file, use ``os.rename(old_path, new_path)``."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:463
|
|
msgid ""
|
|
"To truncate a file, open it using ``f = open(filename, \"r+\")``, and use "
|
|
"``f.truncate(offset)``; offset defaults to the current seek position. "
|
|
"There's also ``os.ftruncate(fd, offset)`` for files opened with :func:`os."
|
|
"open`, where *fd* is the file descriptor (a small integer)."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:468
|
|
msgid ""
|
|
"The :mod:`shutil` module also contains a number of functions to work on "
|
|
"files including :func:`~shutil.copyfile`, :func:`~shutil.copytree`, and :"
|
|
"func:`~shutil.rmtree`."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:474
|
|
msgid "How do I copy a file?"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:476
|
|
msgid ""
|
|
"The :mod:`shutil` module contains a :func:`~shutil.copyfile` function. Note "
|
|
"that on MacOS 9 it doesn't copy the resource fork and Finder info."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:481
|
|
msgid "How do I read (or write) binary data?"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:483
|
|
msgid ""
|
|
"To read or write complex binary data formats, it's best to use the :mod:"
|
|
"`struct` module. It allows you to take a string containing binary data "
|
|
"(usually numbers) and convert it to Python objects; and vice versa."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:487
|
|
msgid ""
|
|
"For example, the following code reads two 2-byte integers and one 4-byte "
|
|
"integer in big-endian format from a file::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:496
|
|
msgid ""
|
|
"The '>' in the format string forces big-endian data; the letter 'h' reads "
|
|
"one \"short integer\" (2 bytes), and 'l' reads one \"long integer\" (4 "
|
|
"bytes) from the string."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:500
|
|
msgid ""
|
|
"For data that is more regular (e.g. a homogeneous list of ints or floats), "
|
|
"you can also use the :mod:`array` module."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:505
|
|
msgid "I can't seem to use os.read() on a pipe created with os.popen(); why?"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:507
|
|
msgid ""
|
|
":func:`os.read` is a low-level function which takes a file descriptor, a "
|
|
"small integer representing the opened file. :func:`os.popen` creates a high-"
|
|
"level file object, the same type returned by the built-in :func:`open` "
|
|
"function. Thus, to read *n* bytes from a pipe *p* created with :func:`os."
|
|
"popen`, you need to use ``p.read(n)``."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:515
|
|
msgid ""
|
|
"How do I run a subprocess with pipes connected to both input and output?"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:519
|
|
msgid "Use the :mod:`popen2` module. For example::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:527
|
|
msgid ""
|
|
"Warning: in general it is unwise to do this because you can easily cause a "
|
|
"deadlock where your process is blocked waiting for output from the child "
|
|
"while the child is blocked waiting for input from you. This can be caused "
|
|
"by the parent expecting the child to output more text than it does or by "
|
|
"data being stuck in stdio buffers due to lack of flushing. The Python "
|
|
"parent can of course explicitly flush the data it sends to the child before "
|
|
"it reads any output, but if the child is a naive C program it may have been "
|
|
"written to never explicitly flush its output, even if it is interactive, "
|
|
"since flushing is normally automatic."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:537
|
|
msgid ""
|
|
"Note that a deadlock is also possible if you use :func:`popen3` to read "
|
|
"stdout and stderr. If one of the two is too large for the internal buffer "
|
|
"(increasing the buffer size does not help) and you ``read()`` the other one "
|
|
"first, there is a deadlock, too."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:542
|
|
msgid ""
|
|
"Note on a bug in popen2: unless your program calls ``wait()`` or "
|
|
"``waitpid()``, finished child processes are never removed, and eventually "
|
|
"calls to popen2 will fail because of a limit on the number of child "
|
|
"processes. Calling :func:`os.waitpid` with the :data:`os.WNOHANG` option "
|
|
"can prevent this; a good place to insert such a call would be before calling "
|
|
"``popen2`` again."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:548
|
|
msgid ""
|
|
"In many cases, all you really need is to run some data through a command and "
|
|
"get the result back. Unless the amount of data is very large, the easiest "
|
|
"way to do this is to write it to a temporary file and run the command with "
|
|
"that temporary file as input. The standard module :mod:`tempfile` exports "
|
|
"a :func:`~tempfile.mktemp` function to generate unique temporary file "
|
|
"names. ::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:583
|
|
msgid ""
|
|
"Note that many interactive programs (e.g. vi) don't work well with pipes "
|
|
"substituted for standard input and output. You will have to use pseudo ttys "
|
|
"(\"ptys\") instead of pipes. Or you can use a Python interface to Don Libes' "
|
|
"\"expect\" library. A Python extension that interfaces to expect is called "
|
|
"\"expy\" and available from http://expectpy.sourceforge.net. A pure Python "
|
|
"solution that works like expect is `pexpect <https://pypi.python.org/pypi/"
|
|
"pexpect/>`_."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:592
|
|
msgid "How do I access the serial (RS232) port?"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:594
|
|
msgid "For Win32, POSIX (Linux, BSD, etc.), Jython:"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:596
|
|
msgid "http://pyserial.sourceforge.net"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:598
|
|
msgid "For Unix, see a Usenet post by Mitch Chapman:"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:600
|
|
msgid "https://groups.google.com/groups?selm=34A04430.CF9@ohioee.com"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:604
|
|
msgid "Why doesn't closing sys.stdout (stdin, stderr) really close it?"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:606
|
|
msgid ""
|
|
"Python file objects are a high-level layer of abstraction on top of C "
|
|
"streams, which in turn are a medium-level layer of abstraction on top of "
|
|
"(among other things) low-level C file descriptors."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:610
|
|
msgid ""
|
|
"For most file objects you create in Python via the built-in ``file`` "
|
|
"constructor, ``f.close()`` marks the Python file object as being closed from "
|
|
"Python's point of view, and also arranges to close the underlying C stream. "
|
|
"This also happens automatically in ``f``'s destructor, when ``f`` becomes "
|
|
"garbage."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:616
|
|
msgid ""
|
|
"But stdin, stdout and stderr are treated specially by Python, because of the "
|
|
"special status also given to them by C. Running ``sys.stdout.close()`` "
|
|
"marks the Python-level file object as being closed, but does *not* close the "
|
|
"associated C stream."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:621
|
|
msgid ""
|
|
"To close the underlying C stream for one of these three, you should first be "
|
|
"sure that's what you really want to do (e.g., you may confuse extension "
|
|
"modules trying to do I/O). If it is, use os.close::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:631
|
|
msgid "Network/Internet Programming"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:634
|
|
msgid "What WWW tools are there for Python?"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:636
|
|
msgid ""
|
|
"See the chapters titled :ref:`internet` and :ref:`netdata` in the Library "
|
|
"Reference Manual. Python has many modules that will help you build server-"
|
|
"side and client-side web systems."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:642
|
|
msgid ""
|
|
"A summary of available frameworks is maintained by Paul Boddie at https://"
|
|
"wiki.python.org/moin/WebProgramming\\ ."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:645
|
|
msgid ""
|
|
"Cameron Laird maintains a useful set of pages about Python web technologies "
|
|
"at http://phaseit.net/claird/comp.lang.python/web_python."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:650
|
|
msgid "How can I mimic CGI form submission (METHOD=POST)?"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:652
|
|
msgid ""
|
|
"I would like to retrieve web pages that are the result of POSTing a form. Is "
|
|
"there existing code that would let me do this easily?"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:655
|
|
msgid "Yes. Here's a simple example that uses httplib::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:679
|
|
msgid ""
|
|
"Note that in general for percent-encoded POST operations, query strings must "
|
|
"be quoted using :func:`urllib.urlencode`. For example, to send ``name=Guy "
|
|
"Steele, Jr.``::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:689
|
|
msgid "What module should I use to help with generating HTML?"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:693
|
|
msgid ""
|
|
"You can find a collection of useful links on the `Web Programming wiki page "
|
|
"<https://wiki.python.org/moin/WebProgramming>`_."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:698
|
|
msgid "How do I send mail from a Python script?"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:700
|
|
msgid "Use the standard library module :mod:`smtplib`."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:702
|
|
msgid ""
|
|
"Here's a very simple interactive mail sender that uses it. This method will "
|
|
"work on any host that supports an SMTP listener. ::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:722
|
|
msgid ""
|
|
"A Unix-only alternative uses sendmail. The location of the sendmail program "
|
|
"varies between systems; sometimes it is ``/usr/lib/sendmail``, sometimes ``/"
|
|
"usr/sbin/sendmail``. The sendmail manual page will help you out. Here's "
|
|
"some sample code::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:742
|
|
msgid "How do I avoid blocking in the connect() method of a socket?"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:744
|
|
msgid ""
|
|
"The select module is commonly used to help with asynchronous I/O on sockets."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:746
|
|
msgid ""
|
|
"To prevent the TCP connect from blocking, you can set the socket to non-"
|
|
"blocking mode. Then when you do the ``connect()``, you will either connect "
|
|
"immediately (unlikely) or get an exception that contains the error number as "
|
|
"``.errno``. ``errno.EINPROGRESS`` indicates that the connection is in "
|
|
"progress, but hasn't finished yet. Different OSes will return different "
|
|
"values, so you're going to have to check what's returned on your system."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:753
|
|
msgid ""
|
|
"You can use the ``connect_ex()`` method to avoid creating an exception. It "
|
|
"will just return the errno value. To poll, you can call ``connect_ex()`` "
|
|
"again later -- 0 or ``errno.EISCONN`` indicate that you're connected -- or "
|
|
"you can pass this socket to select to check if it's writable."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:760
|
|
msgid "Databases"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:763
|
|
msgid "Are there any interfaces to database packages in Python?"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:765
|
|
msgid "Yes."
|
|
msgstr "Oui."
|
|
|
|
#: ../Doc/faq/library.rst:769
|
|
msgid ""
|
|
"Python 2.3 includes the :mod:`bsddb` package which provides an interface to "
|
|
"the BerkeleyDB library. Interfaces to disk-based hashes such as :mod:`DBM "
|
|
"<dbm>` and :mod:`GDBM <gdbm>` are also included with standard Python."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:773
|
|
msgid ""
|
|
"Support for most relational databases is available. See the "
|
|
"`DatabaseProgramming wiki page <https://wiki.python.org/moin/"
|
|
"DatabaseProgramming>`_ for details."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:779
|
|
msgid "How do you implement persistent objects in Python?"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:781
|
|
msgid ""
|
|
"The :mod:`pickle` library module solves this in a very general way (though "
|
|
"you still can't store things like open files, sockets or windows), and the :"
|
|
"mod:`shelve` library module uses pickle and (g)dbm to create persistent "
|
|
"mappings containing arbitrary Python objects. For better performance, you "
|
|
"can use the :mod:`cPickle` module."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:787
|
|
msgid ""
|
|
"A more awkward way of doing things is to use pickle's little sister, "
|
|
"marshal. The :mod:`marshal` module provides very fast ways to store "
|
|
"noncircular basic Python types to files and strings, and back again. "
|
|
"Although marshal does not do fancy things like store instances or handle "
|
|
"shared references properly, it does run extremely fast. For example, "
|
|
"loading a half megabyte of data may take less than a third of a second. "
|
|
"This often beats doing something more complex and general such as using gdbm "
|
|
"with pickle/shelve."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:797
|
|
msgid "Why is cPickle so slow?"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:801
|
|
msgid ""
|
|
"By default :mod:`pickle` uses a relatively old and slow format for backward "
|
|
"compatibility. You can however specify other protocol versions that are "
|
|
"faster::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:810
|
|
msgid ""
|
|
"If my program crashes with a bsddb (or anydbm) database open, it gets "
|
|
"corrupted. How come?"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:812
|
|
msgid ""
|
|
"Databases opened for write access with the bsddb module (and often by the "
|
|
"anydbm module, since it will preferentially use bsddb) must explicitly be "
|
|
"closed using the ``.close()`` method of the database. The underlying "
|
|
"library caches database contents which need to be converted to on-disk form "
|
|
"and written."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:817
|
|
msgid ""
|
|
"If you have initialized a new bsddb database but not written anything to it "
|
|
"before the program crashes, you will often wind up with a zero-length file "
|
|
"and encounter an exception the next time the file is opened."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:823
|
|
msgid ""
|
|
"I tried to open Berkeley DB file, but bsddb produces bsddb.error: (22, "
|
|
"'Invalid argument'). Help! How can I restore my data?"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:825
|
|
msgid ""
|
|
"Don't panic! Your data is probably intact. The most frequent cause for the "
|
|
"error is that you tried to open an earlier Berkeley DB file with a later "
|
|
"version of the Berkeley DB library."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:829
|
|
msgid ""
|
|
"Many Linux systems now have all three versions of Berkeley DB available. If "
|
|
"you are migrating from version 1 to a newer version use db_dump185 to dump a "
|
|
"plain text version of the database. If you are migrating from version 2 to "
|
|
"version 3 use db2_dump to create a plain text version of the database. In "
|
|
"either case, use db_load to create a new native database for the latest "
|
|
"version installed on your computer. If you have version 3 of Berkeley DB "
|
|
"installed, you should be able to use db2_load to create a native version 2 "
|
|
"database."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:837
|
|
msgid ""
|
|
"You should move away from Berkeley DB version 1 files because the hash file "
|
|
"code contains known bugs that can corrupt your data."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:842
|
|
msgid "Mathematics and Numerics"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:845
|
|
msgid "How do I generate random numbers in Python?"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:847
|
|
msgid ""
|
|
"The standard module :mod:`random` implements a random number generator. "
|
|
"Usage is simple::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:853
|
|
msgid "This returns a random floating point number in the range [0, 1)."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:855
|
|
msgid ""
|
|
"There are also many other specialized generators in this module, such as:"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:857
|
|
msgid "``randrange(a, b)`` chooses an integer in the range [a, b)."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:858
|
|
msgid "``uniform(a, b)`` chooses a floating point number in the range [a, b)."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:859
|
|
msgid ""
|
|
"``normalvariate(mean, sdev)`` samples the normal (Gaussian) distribution."
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:861
|
|
msgid "Some higher-level functions operate on sequences directly, such as:"
|
|
msgstr ""
|
|
|
|
#: ../Doc/faq/library.rst:863
|
|
msgid "``choice(S)`` chooses random element from a given sequence"
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msgstr ""
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#: ../Doc/faq/library.rst:864
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msgid "``shuffle(L)`` shuffles a list in-place, i.e. permutes it randomly"
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msgstr ""
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#: ../Doc/faq/library.rst:866
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msgid ""
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"There's also a ``Random`` class you can instantiate to create independent "
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"multiple random number generators."
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msgstr ""
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