Most of our servers have Debian 7, and thus come with Python
2.7. Some of our servers still have Debian 6, so don't have the newest
Python, effectively crippling the newest versions of our photometry
pipelines on these machines. To get around this, we decided to install
the newest Python versions 2.7, and 3.4 (at the time)
in /opt. This works very well, now that we've also
migrated to using Python virtualenv for most
purposes. The new Python wheel binary distribution format is also a
nice perk, so we can quickly install most of the Python scientific
stack without too much pain.
First, we install some required Debian packages.
[root@server:~]# apt-get install build-essential libsqlite3-dev zlib1g-dev libncurses5-dev libgdbm-dev libbz2-dev libreadline5-dev libssl-dev libdb-dev libmysqlclient-dev libblas-dev liblapack-dev libatlas-dev libpng-dev curl libffi-dev
Then, download Python (whatever version you'd like
from the Python website, compile, and
install it to /opt. Below, we give an example of
installing Python 2.7.8, which was current a couple of years
ago. Python 3.5 follows a similar way of installation
(replace /opt/python27
with /opt/python35).
[root@server:~]# tar xvf Python-2.7.8.tgz [root@server:~]# cd Python-2.7.8 [root@server:~]# ./configure --prefix=/opt/python27 [root@server:~]# make -j 4 [root@server:~]# make install
After Python's installed, you can use the version of pip (the Python package manager) that comes with the distribution or bootstrap a virtualenv directly. See here for a newer perspective on this and more details, but a short version of bootstrapping a virtualenv for astronomy work from the downloaded version of the virtualenv package is given below. First, get virtualenv and unpack it somewhere, then do the following for Python 2.7:
[user@server:~]$ /opt/python27/bin/python /path/to/unzipped/virtualenv/virtualenv.py /path/to/new/venv
Python 3.5 comes with virtualenv and pip included as part of the distribution. To use it, do the following:
[user@server:~]$ /opt/python35/bin/python3 -m venv /path/to/new/venv
Now prepare the virtualenv and upgrade pip (the Python package installer):
[user@server:~]$ source /path/to/new/venv/bin/activate (venv)[user@server:~]$ pip install pip --upgrade
Now that the virtualenv is ready, one can install the usual scientific packages and use them while the virtualenv is activated.
(venv)[user@server:~]$ pip install numpy scipy astropy matplotlib ipython[notebook]
