Developer Start Guide

• Learn some non-basic python to understand what’s going on in some of the tricker files (like tensor.py).
• Roughly go through the numpy documentation.
• Learn to write reStructuredText for epydoc.
• ExternalTools - packages that play well with Numpy
• EssentialUnitTest - essential usage of python.unittest

Accounts

To obtain developer access: register with Assembla and add yourself as a watcher on the Theano space. Then send an email to an admin asking to be promoted to a member of the project.

Theano code

To get the source via mercurial, you must have mercurial installed.

The code that makes up Theano is in a single repository. As a developer, you should clone this repository like this:

hg clone 'http://username:password@hg.assembla.com/theano' Theano

You can also clone the code anonymously:

hg clone http://hg.assembla.com/theano Theano

Setting up your environment

Some notes on the environment variable $PYTHONPATH.

The subdirectory Theano/theano has to be located in a location mentionned in your PYTHONPATH. In order to do that, you can either create a symbolic link to Theano/theano in a directory already mentionned in your PYTHONPATH environment variable, or modify the PYTHONPATH so that it mentions Theano.

To create a symbolic link:

ln -s Theano/theano <someplace on your PYTHONPATH>/theano

To modify the environment variable PYTHONPATH in bash, you may do this:

export PYTHONPATH=<path to Theano's parent dir>/Theano:$PYTHONPATH

In csh:

setenv PYTHONPATH <path to Theano's parent dir>/Theano:$PYTHONPATH

Olivier Breuleux explains:

$PYTHONPATH should contain a “:”-separated list of paths, each of which contains one or several Python packages, in the order in which you would like Python to search for them. If a package has sub-packages of interest to you, do _not_ add them in the path: it is not portable, might shadow other packages or short-circuit important things in its __init__.

I advise to never import theano’s files from outside theano itself (and I think that is good advice for Python packages in general). Use “from theano import tensor” instead of “import tensor”. ... $PYTHONPATH ... should only contain paths to complete packages, so you don’t get surprised if I add files that enter in conflict with other packages.

When you install a package, only the package name can be imported directly. If you want a sub-package, you must import it from the main package. That’s how it will work in 99.9% of installs because it is the default. Therefore, if you stray from this practice, your code will not be portable. Also, some ways to circumvent circular dependencies might make it so you have to import files in a certain order, which is best handled by the package’s own __init__.py.

More instructions

Once you have completed these steps, you should run the tests like this:

cd Theano
nosetests #execute all the tests

All tests should pass. If some test fails on your machine, you are encouraged to tell us what went wrong on the theano-users@googlegroups.com mailing list.

To update your library to the latest revision, change directory (cd) to your Theano folder and execute the following command:

hg pull -u

Nightly test

Each night we execute all the unit tests automatically. The result is sent by email to one of the developers, who (at his discretion) forwards it to the mailing list. Said developer may not read his email obsessively (especially on the weekend) so there might be some latency in the process. For more detail see.