def __init__(self, **kwds):
#
# Call base class constructor
#
kwds['type'] = 'xpress'
ILMLicensedSystemCallSolver.__init__(self, **kwds)
self.is_mip = kwds.pop('is_mip', False)
#
# Define valid problem formats and associated results formats
#
self._valid_problem_formats = [ProblemFormat.cpxlp, ProblemFormat.mps]
self._valid_result_formats = {}
self._valid_result_formats[ProblemFormat.cpxlp] = [ResultsFormat.soln]
self._valid_result_formats[ProblemFormat.mps] = [ResultsFormat.soln]
self.set_problem_format(ProblemFormat.cpxlp)
#
# Cache the problem type - LP or MIP. Xpress needs to know this
# on the command-line, and it matters when reading the solution file.
#
# Note: Undefined capabilities default to 'None'
self._capabilities = Options()
self._capabilities.linear = True
self._capabilities.quadratic_objective = True
self._capabilities.quadratic_constraint = True
self._capabilities.integer = True
self._capabilities.sos1 = True
self._capabilities.sos2 = True
def __init__(self, **kwds):
#
# Call base class constructor
#
kwds['type'] = 'cplex'
ILMLicensedSystemCallSolver.__init__(self, **kwds)
# NOTE: eventually both of the following attributes should be migrated to a common base class.
# is the current solve warm-started? a transient data member to communicate state information
# across the _presolve, _apply_solver, and _postsolve methods.
self._warm_start_solve = False
# related to the above, the temporary name of the MST warm-start file (if any).
self._warm_start_file_name = None
#
# Define valid problem formats and associated results formats
#
self._valid_problem_formats = [ProblemFormat.cpxlp, ProblemFormat.mps]
self._valid_result_formats = {}
self._valid_result_formats[ProblemFormat.cpxlp] = [ResultsFormat.soln]
self._valid_result_formats[ProblemFormat.mps] = [ResultsFormat.soln]
self.set_problem_format(ProblemFormat.cpxlp)
# Note: Undefined capabilities default to 'None'
self._capabilities = Options()
self._capabilities.linear = True
self._capabilities.quadratic_objective = True
self._capabilities.quadratic_constraint = True
self._capabilities.integer = True
self._capabilities.sos1 = True
self._capabilities.sos2 = True
def _presolve(self, *args, **kwds):
# create a context in the temporary file manager for
# this plugin - is "pop"ed in the _postsolve method.
TempfileManager.push()
# if the first argument is a string (representing a filename),
# then we don't have an instance => the solver is being applied
# to a file.
self._warm_start_solve = kwds.pop('warmstart', False)
self._warm_start_file_name = kwds.pop('warmstart_file', None)
user_warmstart = False
if self._warm_start_file_name is not None:
user_warmstart = True
# the input argument can currently be one of two things: an
# instance or a filename. if a filename is provided and a
# warm-start is indicated, we go ahead and create the temporary
# file - assuming that the user has already, via some external
# mechanism, invoked warm_start() with a instance to create the
# warm start file.
if self._warm_start_solve and \
isinstance(args[0], str):
# we assume the user knows what they are doing...
pass
elif self._warm_start_solve and \
(not isinstance(args[0], str)):
# assign the name of the warm start file *before* calling
# the base class presolve - the base class method ends up
# creating the command line, and the warm start file-name is
# (obviously) needed there.
if self._warm_start_file_name is None:
assert not user_warmstart
self._warm_start_file_name = TempfileManager.create_tempfile(
suffix='.gurobi.mst')
# let the base class handle any remaining keywords/actions.
ILMLicensedSystemCallSolver._presolve(self, *args, **kwds)
# NB: we must let the base class presolve run first so that the
# symbol_map is actually constructed!
if (len(args) > 0) and (not isinstance(args[0], str)):
if len(args) != 1:
raise ValueError(
"GUROBI _presolve method can only handle a single "
"problem instance - %s were supplied" % (len(args), ))
# write the warm-start file - currently only supports MIPs.
# we only know how to deal with a single problem instance.
if self._warm_start_solve and (not user_warmstart):
start_time = time.time()
self._warm_start(args[0])
end_time = time.time()
if self._report_timing is True:
print("Warm start write time=%.2f seconds" %
(end_time - start_time))
def _postsolve(self):
# take care of the annoying (and empty) CPLEX temporary files in the current directory.
# this approach doesn't seem overly efficient, but python os module functions don't
# accept regular expression directly.
filename_list = os.listdir(".")
for filename in filename_list:
# CPLEX temporary files come in two flavors - cplex.log and clone*.log.
# the latter is the case for multi-processor environments.
# IMPT: trap the possible exception raised by the file not existing.
# this can occur in pyro environments where > 1 workers are
# running CPLEX, and were started from the same directory.
# these logs don't matter anyway (we redirect everything),
# and are largely an annoyance.
try:
if re.match('cplex\.log', filename) != None:
os.remove(filename)
elif re.match('clone\d+\.log', filename) != None:
os.remove(filename)
except OSError:
pass
# let the base class deal with returning results.
results = ILMLicensedSystemCallSolver._postsolve(self)
# finally, clean any temporary files registered with the temp file
# manager, created populated *directly* by this plugin. does not
# include, for example, the execution script. but does include
# the warm-start file.
TempfileManager.pop(remove=not self._keepfiles)
return results
def _postsolve(self):
# take care of the annoying GUROBI log file in the current
# directory. this approach doesn't seem overly efficient, but
# python os module functions doesn't accept regular expression
# directly.
filename_list = os.listdir(".")
for filename in filename_list:
# IMPT: trap the possible exception raised by the file not
# existing. this can occur in pyro environments where
# > 1 workers are running GUROBI, and were started
# from the same directory. these logs don't matter
# anyway (we redirect everything), and are largely an
# annoyance.
try:
if re.match('gurobi\.log', filename) != None:
os.remove(filename)
except OSError:
pass
# let the base class deal with returning results.
results = ILMLicensedSystemCallSolver._postsolve(self)
# finally, clean any temporary files registered with the temp file
# manager, created populated *directly* by this plugin. does not
# include, for example, the execution script. but does include
# the warm-start file.
TempfileManager.pop(remove=not self._keepfiles)
return results
def __init__(self, **kwds):
logger.warning(
"The shell interface for Xpress is broken for recent versions "\
"of Xpress. Please use xpress_direct or xpress_persistent, "\
"which require the Xpress Python API. Python bindings "\
"for recent versions of Xpress can be installed via `pip`: "\
"<https://pypi.org/project/xpress/>.")
#
# Call base class constructor
#
kwds['type'] = 'xpress'
ILMLicensedSystemCallSolver.__init__(self, **kwds)
self.is_mip = kwds.pop('is_mip', False)
#
# Define valid problem formats and associated results formats
#
self._valid_problem_formats = [ProblemFormat.cpxlp, ProblemFormat.mps]
self._valid_result_formats = {}
self._valid_result_formats[ProblemFormat.cpxlp] = [ResultsFormat.soln]
self._valid_result_formats[ProblemFormat.mps] = [ResultsFormat.soln]
self.set_problem_format(ProblemFormat.cpxlp)
#
# Cache the problem type - LP or MIP. Xpress needs to know this
# on the command-line, and it matters when reading the solution file.
#
# Note: Undefined capabilities default to 'None'
self._capabilities = Bunch()
self._capabilities.linear = True
self._capabilities.quadratic_objective = True
self._capabilities.quadratic_constraint = True
self._capabilities.integer = True
self._capabilities.sos1 = True
self._capabilities.sos2 = True
def process_logfile(self):
return ILMLicensedSystemCallSolver.process_logfile(self)
def available(self, exception_flag=False):
val = ILMLicensedSystemCallSolver.available(self, exception_flag)
if not val:
return False
return True
