python-blosc comes with C Blosc sources, so it does not depend on any other library (bar Python itself of course). Of course, if you are going to install from sources, you are going to need a C compiler (GCC, clang and MSVC 2008/2010/2012/2015 have been tested).
Also, there are situations where you may want to link with an already existing Blosc library in your system. You can do that too.
This package supports Python 3.6 or higher versions.
Installing from PyPI repository¶
$ pip install -U blosc
Installing from the Anaconda Cloud¶
$ conda install -c conda-forge python-blosc
First, go to the python-blosc official repository at https://github.com/Blosc/python-blosc and download the sources.
Then, there are different ways to compile python-blosc, depending on whether you want to link with an already installed Blosc library or not.
Installing via setuptools¶
python-blosc comes with the Blosc sources with it and can be built with:
$ python -m pip install -r requirements-dev.txt $ python setup.py build_ext --inplace
Any codec can be enabled (
=1) or disabled (
=0) on this build-path with the appropriate
OS environment variables
INCLUDE_ZLIB. By default all the codecs in Blosc are enabled except Snappy
(due to some issues with C++ with the
setuptools is limited to using the compiler specified in the environment
CC which on posix systems is usually
gcc. This often causes
trouble with the Snappy codec, which is written in C++, and as a result Snappy
is no longer compiled by default. This problem is not known to affect MSVC or
clang. Snappy is considered optional in Blosc as its compression performance
is below that of the other codecs.
That’s all. You can proceed with testing section now.
Compiling with an installed Blosc library¶
This approach uses pre-built, fully optimized versions of Blosc built via CMake.
Go to https://github.com/Blosc/c-blosc/releases and download and install the C-Blosc library. Then, you can tell python-blosc where is the C-Blosc library in a couple of ways:
Using an environment variable:
$ BLOSC_DIR=/usr/local (or "set BLOSC_DIR=\blosc" on Win) $ export BLOSC_DIR (not needed on Win) $ python setup.py build_clib $ python setup.py build_ext --inplace
Using a flag:
$ python setup.py build_clib $ python setup.py build_ext --inplace --blosc=/usr/local
Generating Sphinx documentation¶
In case you want to generate the documentation locally, you will need to
Sphinx documentation system, as well as the
extension, installed. Then go down to
doc/ directory and do:
$ make html|latex|latexpdf
After compiling, you can quickly check that the package is sane by
running the doctests in
$ PYTHONPATH=. (or "set PYTHONPATH=." on Win) $ export PYTHONPATH=. (not needed on Win) $ python blosc/test.py (add -v for verbose mode)
Or alternatively, you can use the third-party
nosetests script to run both
the doctests and the test suite:
$ nosetests --with-doctest (add -v for verbose mode)
Once installed, you can re-run the tests at any time with:
$ python -c "import blosc; blosc.test()"
Install it as a typical Python package:
$ python setup.py install