1# PuLP : Python LP Modeler
2
3# Copyright (c) 2002-2005, Jean-Sebastien Roy (js@jeannot.org)
4# Modifications Copyright (c) 2007- Stuart Anthony Mitchell (s.mitchell@auckland.ac.nz)
5# $Id:constants.py 1791 2008-04-23 22:54:34Z smit023 $
6
7# Permission is hereby granted, free of charge, to any person obtaining a
8# copy of this software and associated documentation files (the
9# "Software"), to deal in the Software without restriction, including
10# without limitation the rights to use, copy, modify, merge, publish,
11# distribute, sublicense, and/or sell copies of the Software, and to
12# permit persons to whom the Software is furnished to do so, subject to
13# the following conditions:
14
15# The above copyright notice and this permission notice shall be included
16# in all copies or substantial portions of the Software.
17
18# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
19# OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
21# IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
22# CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
23# TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
24# SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE."""
25
26"""
27This file contains the constant definitions for PuLP
28Note that hopefully these will be changed into something more pythonic
29"""
30VERSION = "2.6.0"
31EPS = 1e-7
32
33# variable categories
34LpContinuous = "Continuous"
35LpInteger = "Integer"
36LpBinary = "Binary"
37LpCategories = {LpContinuous: "Continuous", LpInteger: "Integer", LpBinary: "Binary"}
38
39# objective sense
40LpMinimize = 1
41LpMaximize = -1
42LpSenses = {LpMaximize: "Maximize", LpMinimize: "Minimize"}
43
44# problem status
45LpStatusNotSolved = 0
46LpStatusOptimal = 1
47LpStatusInfeasible = -1
48LpStatusUnbounded = -2
49LpStatusUndefined = -3
50LpStatus = {
51    LpStatusNotSolved: "Not Solved",
52    LpStatusOptimal: "Optimal",
53    LpStatusInfeasible: "Infeasible",
54    LpStatusUnbounded: "Unbounded",
55    LpStatusUndefined: "Undefined",
56}
57
58# solution status
59LpSolutionNoSolutionFound = 0
60LpSolutionOptimal = 1
61LpSolutionIntegerFeasible = 2
62LpSolutionInfeasible = -1
63LpSolutionUnbounded = -2
64LpSolution = {
65    LpSolutionNoSolutionFound: "No Solution Found",
66    LpSolutionOptimal: "Optimal Solution Found",
67    LpSolutionIntegerFeasible: "Solution Found",
68    LpSolutionInfeasible: "No Solution Exists",
69    LpSolutionUnbounded: "Solution is Unbounded",
70}
71LpStatusToSolution = {
72    LpStatusNotSolved: LpSolutionInfeasible,
73    LpStatusOptimal: LpSolutionOptimal,
74    LpStatusInfeasible: LpSolutionInfeasible,
75    LpStatusUnbounded: LpSolutionUnbounded,
76    LpStatusUndefined: LpSolutionInfeasible,
77}
78
79# constraint sense
80LpConstraintLE = -1
81LpConstraintEQ = 0
82LpConstraintGE = 1
83LpConstraintTypeToMps = {LpConstraintLE: "L", LpConstraintEQ: "E", LpConstraintGE: "G"}
84LpConstraintSenses = {LpConstraintEQ: "=", LpConstraintLE: "<=", LpConstraintGE: ">="}
85# LP line size
86LpCplexLPLineSize = 78
87
88
89def isiterable(obj):
90    try:
91        obj = iter(obj)
92    except:
93        return False
94    else:
95        return True
96
97
98class PulpError(Exception):
99    """
100    Pulp Exception Class
101    """
102
103    pass
104