linear programming in python?

user24562 picture user24562 · May 22, 2012 · Viewed 64.2k times · Source

I need to make a linear programming model. Here are the inequalities I'm using (for example):

6x + 4y <= 24
x + 2y <= 6
-x + y <= 1
y <= 2

I need to find the area described by these inequalities, and shade it in a graph, as well as keep track of the vertices of the bounding lines of this area, and draw the bounding line in a different color. See the graph below for an example of what I'm looking for.

image of the points of intersection.

I'm using Python 3.2, numpy, and matplotlib. Are there better modules for linear programming in Python?

Answer

Ali picture Ali · May 22, 2012

UPDATE: The answer has become somewhat outdated in the past 4 years, here is an update. You have many options:

  • If you do not have to do it Python then it is a lot more easier to do this in a modeling langage, see Any good tools to solve integer programs on linux?

  • I personally use Gurobi these days through its Python API. It is a commercial, closed-source product but free for academic research.

  • With PuLP you can create MPS and LP files and then solve them with GLPK, COIN CLP/CBC, CPLEX, or XPRESS through their command-line interface. This approach has its advantages and disadvantages.

  • The OR-Tools from Google is an open source software suite for optimization, tuned for tackling the world's toughest problems in vehicle routing, flows, integer and linear programming, and constraint programming.

  • Pyomo is a Python-based, open-source optimization modeling language with a diverse set of optimization capabilities.

  • SciPy offers linear programming: scipy.optimize.linprog. (I have never tried this one.)

  • Apparently, CVXOPT offers a Python interface to GLPK, I did not know that. I have been using GLPK for 8 years now and I can highly recommend GLPK. The examples and tutorial of CVXOPT seem really nice!

  • You can find other possibilites at in the Wikibook under GLPK/Python. Note that many of these are not necessarily resticted to GLPK.