# PuLP : Python LP Modeler # Version 1.4.2 # Copyright (c) 2002-2005, Jean-Sebastien Roy (js@jeannot.org) # Modifications Copyright (c) 2007- Stuart Anthony Mitchell (s.mitchell@auckland.ac.nz) # $Id:solvers.py 1791 2008-04-23 22:54:34Z smit023 $ # Permission is hereby granted, free of charge, to any person obtaining a # copy of this software and associated documentation files (the # "Software"), to deal in the Software without restriction, including # without limitation the rights to use, copy, modify, merge, publish, # distribute, sublicense, and/or sell copies of the Software, and to # permit persons to whom the Software is furnished to do so, subject to # the following conditions: # The above copyright notice and this permission notice shall be included # in all copies or substantial portions of the Software. # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS # OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF # MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. # IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY # CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, # TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE # SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.""" from .core import LpSolver_CMD, subprocess, PulpSolverError import os from .. import constants import warnings class CHOCO_CMD(LpSolver_CMD): """The CHOCO_CMD solver""" name = "CHOCO_CMD" def __init__( self, path=None, keepFiles=False, mip=True, msg=True, options=None, timeLimit=None, ): """ :param bool mip: if False, assume LP even if integer variables :param bool msg: if False, no log is shown :param float timeLimit: maximum time for solver (in seconds) :param list options: list of additional options to pass to solver :param bool keepFiles: if True, files are saved in the current directory and not deleted after solving :param str path: path to the solver binary """ LpSolver_CMD.__init__( self, mip=mip, msg=msg, timeLimit=timeLimit, options=options, path=path, keepFiles=keepFiles, ) def defaultPath(self): return self.executableExtension("choco-parsers-with-dependencies.jar") def available(self): """True if the solver is available""" java_path = self.executableExtension("java") return self.executable(self.path) and self.executable(java_path) def actualSolve(self, lp): """Solve a well formulated lp problem""" java_path = self.executableExtension("java") if not self.executable(java_path): raise PulpSolverError( "PuLP: java needs to be installed and accesible in order to use CHOCO_CMD" ) if not os.path.exists(self.path): raise PulpSolverError("PuLP: cannot execute " + self.path) tmpMps, tmpLp, tmpSol = self.create_tmp_files(lp.name, "mps", "lp", "sol") # just to report duplicated variables: lp.checkDuplicateVars() lp.writeMPS(tmpMps, mpsSense=lp.sense) try: os.remove(tmpSol) except: pass cmd = java_path + ' -cp "' + self.path + '" org.chocosolver.parser.mps.ChocoMPS' if self.timeLimit is not None: cmd += f" -tl {self.timeLimit}" * 1000 cmd += " " + " ".join([f"{key} {value}" for key, value in self.options]) cmd += f" {tmpMps}" if lp.sense == constants.LpMaximize: cmd += " -max" if lp.isMIP(): if not self.mip: warnings.warn("CHOCO_CMD cannot solve the relaxation of a problem") # we always get the output to a file. # if not, we cannot read it afterwards # (we thus ignore the self.msg parameter) pipe = open(tmpSol, "w") return_code = subprocess.call(cmd, stdout=pipe, stderr=pipe, shell=True) if return_code != 0: raise PulpSolverError("PuLP: Error while trying to execute " + self.path) if not os.path.exists(tmpSol): status = constants.LpStatusNotSolved status_sol = constants.LpSolutionNoSolutionFound values = None else: status, values, status_sol = self.readsol(tmpSol) self.delete_tmp_files(tmpMps, tmpLp, tmpSol) lp.assignStatus(status, status_sol) if status not in [constants.LpStatusInfeasible, constants.LpStatusNotSolved]: lp.assignVarsVals(values) return status @staticmethod def readsol(filename): """Read a Choco solution file""" # TODO: figure out the unbounded status in choco solver chocoStatus = { "OPTIMUM FOUND": constants.LpStatusOptimal, "SATISFIABLE": constants.LpStatusOptimal, "UNSATISFIABLE": constants.LpStatusInfeasible, "UNKNOWN": constants.LpStatusNotSolved, } chocoSolStatus = { "OPTIMUM FOUND": constants.LpSolutionOptimal, "SATISFIABLE": constants.LpSolutionIntegerFeasible, "UNSATISFIABLE": constants.LpSolutionInfeasible, "UNKNOWN": constants.LpSolutionNoSolutionFound, } status = constants.LpStatusNotSolved sol_status = constants.LpSolutionNoSolutionFound values = {} with open(filename) as f: content = f.readlines() content = [l.strip() for l in content if l[:2] not in ["o ", "c "]] if not len(content): return status, values, sol_status if content[0][:2] == "s ": status_str = content[0][2:] status = chocoStatus[status_str] sol_status = chocoSolStatus[status_str] for line in content[1:]: name, value = line.split() values[name] = float(value) return status, values, sol_status