# ___________________________________________________________________________
#
# Pyomo: Python Optimization Modeling Objects
# Copyright (c) 2008-2024
# National Technology and Engineering Solutions of Sandia, LLC
# Under the terms of Contract DE-NA0003525 with National Technology and
# Engineering Solutions of Sandia, LLC, the U.S. Government retains certain
# rights in this software.
# This software is distributed under the 3-clause BSD License.
# ___________________________________________________________________________
import os
import subprocess
from pyomo.common import Executable
from pyomo.common.collections import Bunch
from pyomo.common.tempfiles import TempfileManager
from pyomo.opt.base import ProblemFormat, ResultsFormat
from pyomo.opt.base.solvers import _extract_version, SolverFactory
from pyomo.opt.results import SolverStatus
from pyomo.opt.solver import SystemCallSolver
import logging
logger = logging.getLogger('pyomo.solvers')
[docs]
@SolverFactory.register('conopt', doc='The CONOPT NLP solver')
class CONOPT(SystemCallSolver):
"""
An interface to the CONOPT optimizer that uses the AMPL Solver Library.
"""
[docs]
def __init__(self, **kwds):
#
# Call base constructor
#
kwds["type"] = "conopt"
super(CONOPT, self).__init__(**kwds)
#
# Setup valid problem formats, and valid results for each problem format
# Also set the default problem and results formats.
#
self._valid_problem_formats = [ProblemFormat.nl]
self._valid_result_formats = {}
self._valid_result_formats[ProblemFormat.nl] = [ResultsFormat.sol]
self.set_problem_format(ProblemFormat.nl)
# Note: Undefined capabilities default to 'None'
self._capabilities = Bunch()
self._capabilities.linear = True
self._capabilities.integer = True
self._capabilities.quadratic_objective = True
self._capabilities.quadratic_constraint = True
self._capabilities.sos1 = True
self._capabilities.sos2 = True
def _default_results_format(self, prob_format):
return ResultsFormat.sol
def _default_executable(self):
executable = Executable("conopt")
if not executable:
logger.warning(
"Could not locate the 'conopt' executable, "
"which is required for solver %s" % self.name
)
self.enable = False
return None
return executable.path()
def _get_version(self):
"""
Returns a tuple describing the solver executable version.
"""
solver_exec = self.executable()
if solver_exec is None:
return _extract_version('')
results = subprocess.run(
[solver_exec],
timeout=self._version_timeout,
stdout=subprocess.PIPE,
stderr=subprocess.STDOUT,
universal_newlines=True,
)
return _extract_version(results.stdout)
[docs]
def create_command_line(self, executable, problem_files):
assert self._problem_format == ProblemFormat.nl
assert self._results_format == ResultsFormat.sol
#
# Define log file
#
if self._log_file is None:
self._log_file = TempfileManager.create_tempfile(suffix="_conopt.log")
fname = problem_files[0]
if '.' in fname:
tmp = fname.split('.')
if len(tmp) > 2:
fname = '.'.join(tmp[:-1])
else:
fname = tmp[0]
self._soln_file = fname + ".sol"
#
# Define results file (since an external parser is used)
#
self._results_file = self._soln_file
#
# Define command line
#
env = os.environ.copy()
#
# Merge the PYOMO_AMPLFUNC (externals defined within
# Pyomo/Pyomo) with any user-specified external function
# libraries
#
if 'PYOMO_AMPLFUNC' in env:
if 'AMPLFUNC' in env:
env['AMPLFUNC'] += "\n" + env['PYOMO_AMPLFUNC']
else:
env['AMPLFUNC'] = env['PYOMO_AMPLFUNC']
cmd = [executable, problem_files[0], '-AMPL']
if self._timer:
cmd.insert(0, self._timer)
# GAH: I am going to re-add the code by Zev that passed options through
# to the command line. I'm not sure what solvers this method of passing options
# through the envstr variable works for, but it does not seem to work for cplex
# or gurobi
opt = []
for key in self.options:
if key == 'solver':
continue
if isinstance(self.options[key], str) and ' ' in self.options[key]:
opt.append(key + "=\"" + str(self.options[key]) + "\"")
cmd.append(str(key) + "=" + str(self.options[key]))
elif key == 'subsolver':
opt.append("solver=" + str(self.options[key]))
cmd.append(str(key) + "=" + str(self.options[key]))
else:
opt.append(key + "=" + str(self.options[key]))
cmd.append(str(key) + "=" + str(self.options[key]))
envstr = "%s_options" % self.options.solver
# Merge with any options coming in through the environment
env[envstr] = " ".join(opt)
return Bunch(cmd=cmd, log_file=self._log_file, env=env)
def _postsolve(self):
results = super(CONOPT, self)._postsolve()
# Hack so that the locally optimal termination
# condition for CONOPT does not trigger a warning.
# For some reason it sets the solver_results_num to
# 100 in this case, which is reserved for cases
# where "optimal solution indicated, but error likely".
if results.solver.id == 100 and 'Locally optimal' in results.solver.message:
results.solver.status = SolverStatus.ok
return results