|
|
.. _tips:
|
|
|
|
|
|
=====================
|
|
|
IPython Tips & Tricks
|
|
|
=====================
|
|
|
|
|
|
The `IPython cookbook <http://ipython.scipy.org/moin/Cookbook>`_ details more
|
|
|
things you can do with IPython.
|
|
|
|
|
|
.. This is not in the current version:
|
|
|
|
|
|
|
|
|
Embed IPython in your programs
|
|
|
------------------------------
|
|
|
|
|
|
A few lines of code are enough to load a complete IPython inside your own
|
|
|
programs, giving you the ability to work with your data interactively after
|
|
|
automatic processing has been completed. See :ref:`the embedding section <embedding>`.
|
|
|
|
|
|
Run doctests
|
|
|
------------
|
|
|
|
|
|
Run your doctests from within IPython for development and debugging. The
|
|
|
special %doctest_mode command toggles a mode where the prompt, output and
|
|
|
exceptions display matches as closely as possible that of the default Python
|
|
|
interpreter. In addition, this mode allows you to directly paste in code that
|
|
|
contains leading '>>>' prompts, even if they have extra leading whitespace
|
|
|
(as is common in doctest files). This combined with the ``%history -t`` call
|
|
|
to see your translated history allows for an easy doctest workflow, where you
|
|
|
can go from doctest to interactive execution to pasting into valid Python code
|
|
|
as needed.
|
|
|
|
|
|
Use IPython to present interactive demos
|
|
|
----------------------------------------
|
|
|
|
|
|
Use the :class:`IPython.lib.demo.Demo` class to load any Python script as an interactive
|
|
|
demo. With a minimal amount of simple markup, you can control the execution of
|
|
|
the script, stopping as needed. See :ref:`here <interactive_demos>` for more.
|
|
|
|
|
|
Suppress output
|
|
|
---------------
|
|
|
|
|
|
Put a ';' at the end of a line to suppress the printing of output. This is
|
|
|
useful when doing calculations which generate long output you are not
|
|
|
interested in seeing.
|
|
|
|
|
|
Lightweight 'version control'
|
|
|
-----------------------------
|
|
|
|
|
|
When you call ``%edit`` with no arguments, IPython opens an empty editor
|
|
|
with a temporary file, and it returns the contents of your editing
|
|
|
session as a string variable. Thanks to IPython's output caching
|
|
|
mechanism, this is automatically stored::
|
|
|
|
|
|
In [1]: %edit
|
|
|
|
|
|
IPython will make a temporary file named: /tmp/ipython_edit_yR-HCN.py
|
|
|
|
|
|
Editing... done. Executing edited code...
|
|
|
|
|
|
hello - this is a temporary file
|
|
|
|
|
|
Out[1]: "print 'hello - this is a temporary file'\n"
|
|
|
|
|
|
Now, if you call ``%edit -p``, IPython tries to open an editor with the
|
|
|
same data as the last time you used %edit. So if you haven't used %edit
|
|
|
in the meantime, this same contents will reopen; however, it will be
|
|
|
done in a new file. This means that if you make changes and you later
|
|
|
want to find an old version, you can always retrieve it by using its
|
|
|
output number, via '%edit _NN', where NN is the number of the output
|
|
|
prompt.
|
|
|
|
|
|
Continuing with the example above, this should illustrate this idea::
|
|
|
|
|
|
In [2]: edit -p
|
|
|
|
|
|
IPython will make a temporary file named: /tmp/ipython_edit_nA09Qk.py
|
|
|
|
|
|
Editing... done. Executing edited code...
|
|
|
|
|
|
hello - now I made some changes
|
|
|
|
|
|
Out[2]: "print 'hello - now I made some changes'\n"
|
|
|
|
|
|
In [3]: edit _1
|
|
|
|
|
|
IPython will make a temporary file named: /tmp/ipython_edit_gy6-zD.py
|
|
|
|
|
|
Editing... done. Executing edited code...
|
|
|
|
|
|
hello - this is a temporary file
|
|
|
|
|
|
IPython version control at work :)
|
|
|
|
|
|
Out[3]: "print 'hello - this is a temporary file'\nprint 'IPython version control at work :)'\n"
|
|
|
|
|
|
|
|
|
This section was written after a contribution by Alexander Belchenko on
|
|
|
the IPython user list.
|
|
|
|
|
|
.. The section below needs to be updated for the new config system.
|
|
|
|
|
|
.. Effective logging
|
|
|
-----------------
|
|
|
|
|
|
.. A very useful suggestion sent in by Robert Kern follows:
|
|
|
|
|
|
.. I recently happened on a nifty way to keep tidy per-project log files. I
|
|
|
made a profile for my project (which is called "parkfield")::
|
|
|
|
|
|
include ipythonrc
|
|
|
|
|
|
# cancel earlier logfile invocation:
|
|
|
|
|
|
logfile ''
|
|
|
|
|
|
execute import time
|
|
|
|
|
|
execute __cmd = '/Users/kern/research/logfiles/parkfield-%s.log rotate'
|
|
|
|
|
|
execute __IP.magic_logstart(__cmd % time.strftime('%Y-%m-%d'))
|
|
|
|
|
|
.. I also added a shell alias for convenience::
|
|
|
|
|
|
alias parkfield="ipython --pylab profile=parkfield"
|
|
|
|
|
|
.. Now I have a nice little directory with everything I ever type in,
|
|
|
organized by project and date.
|
|
|
|
|
|
.. warning::
|
|
|
|
|
|
This example uses the outdated ipythonrc-style configuration files, which no
|
|
|
longer work as of IPython 0.11
|
|
|
|
|
|
|
|
|
|
