linprog.rst

import cdd

cdd

Solving Linear Programs

A class for solving linear programs.

Bases: ~cdd.NumberTypeable

param mat

The matrix to load the linear program from.

type mat

~cdd.Matrix

Methods and Attributes

LinProg.solve(solver=cdd.LPSolverType.DUAL_SIMPLEX)

Solve linear program.

param solver

The method of solution (see ~cdd.LPSolverType).

type solver

int

LinProg.dual_solution

A tuple containing the dual solution.

LinProg.obj_type

Whether we are minimizing or maximizing (see ~cdd.LPObjType).

LinProg.obj_value

The optimal value of the objective function.

LinProg.primal_solution

A tuple containing the primal solution.

LinProg.solver

The type of solver to use (see ~cdd.LPSolverType).

LinProg.status

The status of the linear program (see ~cdd.LPStatusType).

Example

>>> import cdd >>> mat = cdd.Matrix([['4/3',-2,-1],['2/3',0,-1],[0,1,0],[0,0,1]], number_type='fraction') >>> mat.obj_type = cdd.LPObjType.MAX >>> mat.obj_func = (0,3,4) >>> print(mat) begin 4 3 rational 4/3 -2 -1 2/3 0 -1 0 1 0 0 0 1 end maximize 0 3 4 >>> print(mat.obj_func) (0, 3, 4) >>> lp = cdd.LinProg(mat) >>> lp.solve() >>> lp.status == cdd.LPStatusType.OPTIMAL True >>> print(lp.obj_value) 11/3 >>> print(" ".join("{0}".format(val) for val in lp.primal_solution)) 1/3 2/3 >>> print(" ".join("{0}".format(val) for val in lp.dual_solution)) 3/2 5/2