Example #1
0
def expression_to_string(expr, treechecker, labeler=None, smap=None):
    if labeler is not None:
        if smap is None:
            smap = SymbolMap()
        smap.default_labeler = labeler
    visitor = ToGamsVisitor(smap, treechecker)
    return visitor.dfs_postorder_stack(expr)
Example #2
0
def expression_to_string(expr, variables, labeler=None, smap=None):
    if labeler is not None:
        if smap is None:
            smap = SymbolMap()
        smap.default_labeler = labeler
    visitor = ToBaronVisitor(variables, smap)
    return visitor.dfs_postorder_stack(expr)
Example #3
0
    def __call__(self, model, output_filename, solver_capability, io_options):

        # Make sure not to modify the user's dictionary, they may be
        # reusing it outside of this call
        io_options = dict(io_options)

        # NOTE: io_options is a simple dictionary of keyword-value
        #       pairs specific to this writer.
        symbolic_solver_labels = \
            io_options.pop("symbolic_solver_labels", False)
        labeler = io_options.pop("labeler", None)

        # How much effort do we want to put into ensuring the
        # LP file is written deterministically for a Pyomo model:
        #    0 : None
        #    1 : sort keys of indexed components (default)
        #    2 : sort keys AND sort names (over declaration order)
        file_determinism = io_options.pop("file_determinism", 1)

        sorter = SortComponents.unsorted
        if file_determinism >= 1:
            sorter = sorter | SortComponents.indices
            if file_determinism >= 2:
                sorter = sorter | SortComponents.alphabetical

        output_fixed_variable_bounds = \
            io_options.pop("output_fixed_variable_bounds", False)

        # Skip writing constraints whose body section is fixed (i.e.,
        # no variables)
        skip_trivial_constraints = \
            io_options.pop("skip_trivial_constraints", False)

        # Note: Baron does not allow specification of runtime
        #       option outside of this file, so we add support
        #       for them here
        solver_options = io_options.pop("solver_options", {})

        if len(io_options):
            raise ValueError(
                "ProblemWriter_baron_writer passed unrecognized io_options:\n\t"
                + "\n\t".join("%s = %s" % (k, v)
                              for k, v in iteritems(io_options)))

        if symbolic_solver_labels and (labeler is not None):
            raise ValueError("Baron problem writer: Using both the "
                             "'symbolic_solver_labels' and 'labeler' "
                             "I/O options is forbidden")

        if output_filename is None:
            output_filename = model.name + ".bar"

        output_file = open(output_filename, "w")

        # Process the options. Rely on baron to catch
        # and reset bad option values
        output_file.write("OPTIONS {\n")
        summary_found = False
        if len(solver_options):
            for key, val in iteritems(solver_options):
                if (key.lower() == 'summary'):
                    summary_found = True
                if key.endswith("Name"):
                    output_file.write(key + ": \"" + str(val) + "\";\n")
                else:
                    output_file.write(key + ": " + str(val) + ";\n")
        if not summary_found:
            # The 'summary option is defaulted to 0, so that no
            # summary file is generated in the directory where the
            # user calls baron. Check if a user explicitly asked for
            # a summary file.
            output_file.write("Summary: 0;\n")
        output_file.write("}\n\n")

        if symbolic_solver_labels:
            v_labeler = AlphaNumericTextLabeler()
            c_labeler = AlphaNumericTextLabeler()
        elif labeler is None:
            v_labeler = NumericLabeler('x')
            c_labeler = NumericLabeler('c')

        symbol_map = SymbolMap()
        symbol_map.default_labeler = v_labeler
        #sm_bySymbol = symbol_map.bySymbol

        # Cache the list of model blocks so we don't have to call
        # model.block_data_objects() many many times, which is slow
        # for indexed blocks
        all_blocks_list = list(
            model.block_data_objects(active=True,
                                     sort=sorter,
                                     descend_into=True))
        active_components_data_var = {}
        #for block in all_blocks_list:
        #    tmp = active_components_data_var[id(block)] = \
        #          list(obj for obj in block.component_data_objects(Var,
        #                                                           sort=sorter,
        #                                                           descend_into=False))
        #    create_symbols_func(symbol_map, tmp, labeler)

        # GAH: Not sure this is necessary, and also it would break for
        #      non-mutable indexed params so I am commenting out for now.
        #for param_data in active_components_data(block, Param, sort=sorter):
        #instead of checking if param_data._mutable:
        #if not param_data.is_constant():
        #    create_symbol_func(symbol_map, param_data, labeler)

        #symbol_map_variable_ids = set(symbol_map.byObject.keys())
        #object_symbol_dictionary = symbol_map.byObject

        #
        # Go through the objectives and constraints and generate
        # the output so that we can obtain the set of referenced
        # variables.
        #
        equation_section_stream = StringIO()
        referenced_variable_ids, branching_priorities_suffixes = \
            self._write_equations_section(
                model,
                equation_section_stream,
                all_blocks_list,
                active_components_data_var,
                symbol_map,
                c_labeler,
                output_fixed_variable_bounds,
                skip_trivial_constraints,
                sorter)

        #
        # BINARY_VARIABLES, INTEGER_VARIABLES, POSITIVE_VARIABLES, VARIABLES
        #

        BinVars = []
        IntVars = []
        PosVars = []
        Vars = []
        for vid in referenced_variable_ids:
            name = symbol_map.byObject[vid]
            var_data = symbol_map.bySymbol[name]()

            if var_data.is_continuous():
                if var_data.has_lb() and \
                   (self._get_bound(var_data.lb) >= 0):
                    TypeList = PosVars
                else:
                    TypeList = Vars
            elif var_data.is_binary():
                TypeList = BinVars
            elif var_data.is_integer():
                TypeList = IntVars
            else:
                assert False
            TypeList.append(name)

        if len(BinVars) > 0:
            BinVars.sort()
            output_file.write('BINARY_VARIABLES ')
            output_file.write(", ".join(BinVars))
            output_file.write(';\n\n')

        if len(IntVars) > 0:
            IntVars.sort()
            output_file.write('INTEGER_VARIABLES ')
            output_file.write(", ".join(IntVars))
            output_file.write(';\n\n')

        PosVars.append('ONE_VAR_CONST__')
        PosVars.sort()
        output_file.write('POSITIVE_VARIABLES ')
        output_file.write(", ".join(PosVars))
        output_file.write(';\n\n')

        if len(Vars) > 0:
            Vars.sort()
            output_file.write('VARIABLES ')
            output_file.write(", ".join(Vars))
            output_file.write(';\n\n')

        #
        # LOWER_BOUNDS
        #

        lbounds = {}
        for vid in referenced_variable_ids:
            name = symbol_map.byObject[vid]
            var_data = symbol_map.bySymbol[name]()

            if var_data.fixed:
                if output_fixed_variable_bounds:
                    var_data_lb = var_data.value
                else:
                    var_data_lb = None
            else:
                var_data_lb = None
                if var_data.has_lb():
                    var_data_lb = self._get_bound(var_data.lb)

            if var_data_lb is not None:
                name_to_output = symbol_map.getSymbol(var_data)
                lb_string_template = '%s: %' + self._precision_string + ';\n'
                lbounds[name_to_output] = lb_string_template % (name_to_output,
                                                                var_data_lb)

        if len(lbounds) > 0:
            output_file.write("LOWER_BOUNDS{\n")
            output_file.write("".join(lbounds[key]
                                      for key in sorted(lbounds.keys())))
            output_file.write("}\n\n")
        lbounds = None

        #
        # UPPER_BOUNDS
        #

        ubounds = {}
        for vid in referenced_variable_ids:
            name = symbol_map.byObject[vid]
            var_data = symbol_map.bySymbol[name]()

            if var_data.fixed:
                if output_fixed_variable_bounds:
                    var_data_ub = var_data.value
                else:
                    var_data_ub = None
            else:
                var_data_ub = None
                if var_data.has_ub():
                    var_data_ub = self._get_bound(var_data.ub)

            if var_data_ub is not None:
                name_to_output = symbol_map.getSymbol(var_data)
                ub_string_template = '%s: %' + self._precision_string + ';\n'
                ubounds[name_to_output] = ub_string_template % (name_to_output,
                                                                var_data_ub)

        if len(ubounds) > 0:
            output_file.write("UPPER_BOUNDS{\n")
            output_file.write("".join(ubounds[key]
                                      for key in sorted(ubounds.keys())))
            output_file.write("}\n\n")
        ubounds = None

        #
        # BRANCHING_PRIORITIES
        #

        # Specifying priorities requires that the pyomo model has established an
        # EXTERNAL, float suffix called 'branching_priorities' on the model
        # object, indexed by the relevant variable
        BranchingPriorityHeader = False
        for suffix in branching_priorities_suffixes:
            for var_data, priority in iteritems(suffix):
                if id(var_data) not in referenced_variable_ids:
                    continue
                if priority is not None:
                    if not BranchingPriorityHeader:
                        output_file.write('BRANCHING_PRIORITIES{\n')
                        BranchingPriorityHeader = True
                    name_to_output = symbol_map.getSymbol(var_data)
                    output_file.write(name_to_output + ': ' + str(priority) +
                                      ';\n')

        if BranchingPriorityHeader:
            output_file.write("}\n\n")

        #
        # Now write the objective and equations section
        #
        output_file.write(equation_section_stream.getvalue())

        #
        # STARTING_POINT
        #
        output_file.write('STARTING_POINT{\nONE_VAR_CONST__: 1;\n')
        tmp = {}
        string_template = '%s: %' + self._precision_string + ';\n'
        for vid in referenced_variable_ids:
            name = symbol_map.byObject[vid]
            var_data = symbol_map.bySymbol[name]()

            starting_point = var_data.value
            if starting_point is not None:
                var_name = symbol_map.getSymbol(var_data)
                tmp[var_name] = string_template % (var_name, starting_point)

        output_file.write("".join(tmp[key] for key in sorted(tmp.keys())))
        output_file.write('}\n\n')

        output_file.close()

        return output_filename, symbol_map
Example #4
0
    def __call__(self,
                 model,
                 output_filename,
                 solver_capability,
                 io_options):

        # Make sure not to modify the user's dictionary, they may be
        # reusing it outside of this call
        io_options = dict(io_options)

        # NOTE: io_options is a simple dictionary of keyword-value
        #       pairs specific to this writer.
        symbolic_solver_labels = \
            io_options.pop("symbolic_solver_labels", False)
        labeler = io_options.pop("labeler", None)

        # How much effort do we want to put into ensuring the
        # LP file is written deterministically for a Pyomo model:
        #    0 : None
        #    1 : sort keys of indexed components (default)
        #    2 : sort keys AND sort names (over declaration order)
        file_determinism = io_options.pop("file_determinism", 1)

        sorter = SortComponents.unsorted
        if file_determinism >= 1:
            sorter = sorter | SortComponents.indices
            if file_determinism >= 2:
                sorter = sorter | SortComponents.alphabetical

        output_fixed_variable_bounds = \
            io_options.pop("output_fixed_variable_bounds", False)

        # Skip writing constraints whose body section is fixed (i.e.,
        # no variables)
        skip_trivial_constraints = \
            io_options.pop("skip_trivial_constraints", False)

        # Note: Baron does not allow specification of runtime
        #       option outside of this file, so we add support
        #       for them here
        solver_options = io_options.pop("solver_options", {})

        if len(io_options):
            raise ValueError(
                "ProblemWriter_baron_writer passed unrecognized io_options:\n\t" +
                "\n\t".join("%s = %s" % (k,v) for k,v in iteritems(io_options)))

        if symbolic_solver_labels and (labeler is not None):
            raise ValueError("Baron problem writer: Using both the "
                             "'symbolic_solver_labels' and 'labeler' "
                             "I/O options is forbidden")

        # Make sure there are no strange ActiveComponents. The expression
        # walker will handle strange things in constraints later.
        model_ctypes = model.collect_ctypes(active=True)
        invalids = set()
        for t in (model_ctypes - valid_active_ctypes_minlp):
            if issubclass(t, ActiveComponent):
                invalids.add(t)
        if len(invalids):
            invalids = [t.__name__ for t in invalids]
            raise RuntimeError(
                "Unallowable active component(s) %s.\nThe BARON writer cannot "
                "export models with this component type." %
                ", ".join(invalids))

        if output_filename is None:
            output_filename = model.name + ".bar"

        output_file=open(output_filename, "w")

        # Process the options. Rely on baron to catch
        # and reset bad option values
        output_file.write("OPTIONS {\n")
        summary_found = False
        if len(solver_options):
            for key, val in iteritems(solver_options):
                if (key.lower() == 'summary'):
                    summary_found = True
                if key.endswith("Name"):
                    output_file.write(key+": \""+str(val)+"\";\n")
                else:
                    output_file.write(key+": "+str(val)+";\n")
        if not summary_found:
            # The 'summary option is defaulted to 0, so that no
            # summary file is generated in the directory where the
            # user calls baron. Check if a user explicitly asked for
            # a summary file.
            output_file.write("Summary: 0;\n")
        output_file.write("}\n\n")

        if symbolic_solver_labels:
            v_labeler = AlphaNumericTextLabeler()
            c_labeler = AlphaNumericTextLabeler()
        elif labeler is None:
            v_labeler = NumericLabeler('x')
            c_labeler = NumericLabeler('c')

        symbol_map = SymbolMap()
        symbol_map.default_labeler = v_labeler
        #sm_bySymbol = symbol_map.bySymbol

        # Cache the list of model blocks so we don't have to call
        # model.block_data_objects() many many times, which is slow
        # for indexed blocks
        all_blocks_list = list(model.block_data_objects(active=True,
                                                        sort=sorter,
                                                        descend_into=True))
        active_components_data_var = {}
        #for block in all_blocks_list:
        #    tmp = active_components_data_var[id(block)] = \
        #          list(obj for obj in block.component_data_objects(Var,
        #                                                           sort=sorter,
        #                                                           descend_into=False))
        #    create_symbols_func(symbol_map, tmp, labeler)

            # GAH: Not sure this is necessary, and also it would break for
            #      non-mutable indexed params so I am commenting out for now.
            #for param_data in active_components_data(block, Param, sort=sorter):
                #instead of checking if param_data._mutable:
                #if not param_data.is_constant():
                #    create_symbol_func(symbol_map, param_data, labeler)

        #symbol_map_variable_ids = set(symbol_map.byObject.keys())
        #object_symbol_dictionary = symbol_map.byObject

        #
        # Go through the objectives and constraints and generate
        # the output so that we can obtain the set of referenced
        # variables.
        #
        equation_section_stream = StringIO()
        referenced_variable_ids, branching_priorities_suffixes = \
            self._write_equations_section(
                model,
                equation_section_stream,
                all_blocks_list,
                active_components_data_var,
                symbol_map,
                c_labeler,
                output_fixed_variable_bounds,
                skip_trivial_constraints,
                sorter)

        #
        # BINARY_VARIABLES, INTEGER_VARIABLES, POSITIVE_VARIABLES, VARIABLES
        #

        BinVars = []
        IntVars = []
        PosVars = []
        Vars = []
        for vid in referenced_variable_ids:
            name = symbol_map.byObject[vid]
            var_data = symbol_map.bySymbol[name]()

            if var_data.is_continuous():
                if var_data.has_lb() and \
                   (self._get_bound(var_data.lb) >= 0):
                    TypeList = PosVars
                else:
                    TypeList = Vars
            elif var_data.is_binary():
                TypeList = BinVars
            elif var_data.is_integer():
                TypeList = IntVars
            else:
                assert False
            TypeList.append(name)

        if len(BinVars) > 0:
            BinVars.sort()
            output_file.write('BINARY_VARIABLES ')
            output_file.write(", ".join(BinVars))
            output_file.write(';\n\n')

        if len(IntVars) > 0:
            IntVars.sort()
            output_file.write('INTEGER_VARIABLES ')
            output_file.write(", ".join(IntVars))
            output_file.write(';\n\n')

        PosVars.append('ONE_VAR_CONST__')
        PosVars.sort()
        output_file.write('POSITIVE_VARIABLES ')
        output_file.write(", ".join(PosVars))
        output_file.write(';\n\n')

        if len(Vars) > 0:
            Vars.sort()
            output_file.write('VARIABLES ')
            output_file.write(", ".join(Vars))
            output_file.write(';\n\n')

        #
        # LOWER_BOUNDS
        #

        lbounds = {}
        for vid in referenced_variable_ids:
            name = symbol_map.byObject[vid]
            var_data = symbol_map.bySymbol[name]()

            if var_data.fixed:
                if output_fixed_variable_bounds:
                    var_data_lb = var_data.value
                else:
                    var_data_lb = None
            else:
                var_data_lb = None
                if var_data.has_lb():
                    var_data_lb = self._get_bound(var_data.lb)

            if var_data_lb is not None:
                name_to_output = symbol_map.getSymbol(var_data)
                lb_string_template = '%s: %'+self._precision_string+';\n'
                lbounds[name_to_output] = lb_string_template % (name_to_output, var_data_lb)

        if len(lbounds) > 0:
            output_file.write("LOWER_BOUNDS{\n")
            output_file.write("".join( lbounds[key] for key in sorted(lbounds.keys()) ) )
            output_file.write("}\n\n")
        lbounds = None

        #
        # UPPER_BOUNDS
        #

        ubounds = {}
        for vid in referenced_variable_ids:
            name = symbol_map.byObject[vid]
            var_data = symbol_map.bySymbol[name]()

            if var_data.fixed:
                if output_fixed_variable_bounds:
                    var_data_ub = var_data.value
                else:
                    var_data_ub = None
            else:
                var_data_ub = None
                if var_data.has_ub():
                    var_data_ub = self._get_bound(var_data.ub)

            if var_data_ub is not None:
                name_to_output = symbol_map.getSymbol(var_data)
                ub_string_template = '%s: %'+self._precision_string+';\n'
                ubounds[name_to_output] = ub_string_template % (name_to_output, var_data_ub)

        if len(ubounds) > 0:
            output_file.write("UPPER_BOUNDS{\n")
            output_file.write("".join( ubounds[key] for key in sorted(ubounds.keys()) ) )
            output_file.write("}\n\n")
        ubounds = None

        #
        # BRANCHING_PRIORITIES
        #

        # Specifying priorities requires that the pyomo model has established an
        # EXTERNAL, float suffix called 'branching_priorities' on the model
        # object, indexed by the relevant variable
        BranchingPriorityHeader = False
        for suffix in branching_priorities_suffixes:
            for var_data, priority in iteritems(suffix):
                if id(var_data) not in referenced_variable_ids:
                    continue
                if priority is not None:
                    if not BranchingPriorityHeader:
                        output_file.write('BRANCHING_PRIORITIES{\n')
                        BranchingPriorityHeader = True
                    name_to_output = symbol_map.getSymbol(var_data)
                    output_file.write(name_to_output+': '+str(priority)+';\n')

        if BranchingPriorityHeader:
            output_file.write("}\n\n")

        #
        # Now write the objective and equations section
        #
        output_file.write(equation_section_stream.getvalue())

        #
        # STARTING_POINT
        #
        output_file.write('STARTING_POINT{\nONE_VAR_CONST__: 1;\n')
        tmp = {}
        string_template = '%s: %'+self._precision_string+';\n'
        for vid in referenced_variable_ids:
            name = symbol_map.byObject[vid]
            var_data = symbol_map.bySymbol[name]()

            starting_point = var_data.value
            if starting_point is not None:
                var_name = symbol_map.getSymbol(var_data)
                tmp[var_name] = string_template % (var_name, starting_point)

        output_file.write("".join( tmp[key] for key in sorted(tmp.keys()) ))
        output_file.write('}\n\n')

        output_file.close()

        return output_filename, symbol_map