Installing pygrametl is fairly simple, mainly due to the library having no mandatory dependencies. This short guide contains all the information needed to get the framework up and running on CPython, pygrametl also runs on top of the JVM based Python implementation, Jython. For more information about running pygrametl on Jython see Jython.
Pygrametl requires an implementation of the Python programming language to run. Currently, pygrametl supports the following implementations:
After either implementations have been installed and added to the system’s path, they can be run from either the command prompt in Windows or the shell in Unix-like systems. This should launch the Python interpreter in interactive mode allowing commands to be executed directly on the command line.
Python 2.7.6 (default, Feb 26 2014, 12:07:17) [GCC 4.8.2 20140206 (prerelease)] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>>
Pygrametl can either be installed from PyPI using a package manager such as Pip or Conda, or by manually checking out the latest development version from the official Github repository. Installing pygrametl from PyPI is currently the simplest way to install pygrametl as the process is automated by the package manager. Bug fixes and new experimental features are, however, of course available first at the Github repository.
Installing pygrametl from PyPI can as be done either to a globally available directory or locally to the user’s home directory. Installing pygrametl globally will on most systems require root or administrator privileges with the advantage that the framework will be available for all users of that system, installing it in the user’s home directory will only make it available to that particular user, but the installation can be performed without additional privileges. Either of the two types of installation can be performed using one of the two following commands.
# Command for installing pygrametl global package diretory $ pip install pygrametl # Command for installing pygrametl user package direcotry $ pip install pygrametl --user
Conda is an alternative package manager for Python, bundled with the Anaconda distribution of Python created by Continuum Analytics. Pygrametl does not currently provide a package for Conda, as it uses a different package format then Pip. It is however trivial to download, convert and install the package from PyPI using Conda with a only few commands.
# Create a template for the Conda package using the PyPI package $ conda skeleton pypi pygrametl # Build the Conda package $ conda build # Install the Coda package $ conda install --use-local pygrametl
After the installation process is completed, the folder containing the package template can be deleted, as it is only used for building the package.
In order to get the latest development version the source code can be downloaded from the official Github repository. The project currently uses Git as version control system, so the repository can be cloned using the following command.
# Clone the pygrametl repository from Github $ git clone https://github.com/chrthomsen/pygrametl.git
In order for Python to import the modules, it be added to sys.path either directly in the source code of your Python programs, or by setting PYTHONPATH if CPython is used, or JYTHONPATH if Jython is used. More information about how Python modules and Jython Modules are located can be found in the two links provided.
A simple way to verify that pygrametl has been installed correctly and is accessible to the Python interpreter, is to start the interpreter in interactive mode from the command line and run the command import pygrametl.
Python 2.7.6 (default, Feb 26 2014, 12:07:17) [GCC 4.8.2 20140206 (prerelease)] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> import pygrametl >>>
If this fails with the message ImportError: No module named pygrametl then verify that the install location of the package is included in either the environment variable, PYTHONPATH if CPython is used, or the environment variable JYTHONPATH if Jython is used. By including the location of pygrametl in these variables, it is available to all instances of that Python implementation just like any built-in Python library. As an alternative, the path to pygrametl can be set on a program to program basis, by adding the path of pygrametl to sys.path, before importing the package in your code.
# The path to the to the pygramelt library is added to the path used by the # by the Python interpreter when libraries are being imported, this must be # done in all program using a module not included in the global Python path sys.path.append('/path/to/pygrametl') # After the folder have been added to Pythons path can the pygrametl # package and all its modules be imported just like any other module import pygrametl