/pplpy

A Python wrapper for the Parma Polyhedra Library (PPL)

Primary LanguagePythonGNU General Public License v3.0GPL-3.0

PPL Python wrapper

This Python package provides a wrapper to the C++ Parma Polyhedra Library (PPL).

The whole package started as a fork of a tiny part of the Sage software.

How it works

The names of objects and methods are the same as in the library:

>>> import ppl
>>> x = ppl.Variable(0)
>>> y = ppl.Variable(1)
>>> z = ppl.Variable(2)
>>> cs = ppl.Constraint_System()
>>> cs.insert(x >= 0)
>>> cs.insert(y >= 0)
>>> cs.insert(z >= 0)
>>> cs.insert(x + y + z == 1)
>>> poly = ppl.C_Polyhedron(cs)
>>> poly.minimized_generators()
Generator_System {point(1/1, 0/1, 0/1), point(0/1, 1/1, 0/1), point(0/1, 0/1, 1/1)}

The available objects and functions from the ppl Python module are:

  • Variable, Variables_Set, Linear_Expression (defined in ppl.linear_algebra)
  • MIP_Problem (defined in ppl.mip_problem)
  • C_Polyhedron, NNC_Polyhedron (defined in ppl.polyhedron)
  • Generator, Generator_System, Poly_Gen_Relation, point, closure_point, ray, line (defined in ppl.generator)
  • Constraint, Constraint_System, Poly_Con_Relation, inequality, equation, strict_inequality (defined in ppl.constraint)

Installation

The project is available at Python Package Index and can be installed with pip:

$ pip install pplpy

Note that if you have gmp and ppl installed in a non standard directory (e.g. you use brew on MacOSX) then you need to set appropriately the variables CFLAGS before calling pip. For example:

$ export CFLAGS="-I/path/to/gmp/include/ -L/path/to/gmp/lib/ -I/path/to/ppl/include/ -L/path/to/ppl/lib $CFLAGS"
$ pip install pplpy

Using from Cython

All Python classes from pplpy are extension types and can be used with Cython. Each extension type carries an attribute thisptr that holds a pointer to the corresponding C++ object from ppl.

A complete example is provided with the files tests/testpplpy.pyx and tests/setup.py.

Source

You can find the latest version of the source code on gitlab: https://gitlab.com/videlec/pplpy

Documentation

The documentation is available at http://pythonhosted.org/pplpy/

License

pplpy is distributed under the terms of the GNU General Public License (GPL) published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version. See http://www.gnu.org/licenses/.

Requirements

On Debian/Ubuntu systems these can be installed with:

$ sudo apt-get install libgmp-dev libmpfr-dev libmpc-dev libppl-dev cython
$ sudo pip install cysignals [--user]
$ pip install gmpy2==2.1.0a1 --no-binary ":all:" [--user]

The pip optional option --user allows to install python packages for a single user with no need for administrator rights.