def read_one_solution(cls, xml_solution, mdl, mst_path):
new_mipstart_sol = cls.new_empty_mipstart(mdl)
nb_missed = 0
effort_level = EffortLevel.Auto
for child in xml_solution:
if child.tag == "header":
obj_s = child.attrib.get('objectiveValue')
if obj_s is not None:
new_mipstart_sol.set_objective_value(float(obj_s))
# an optional mip start name
sol_name = child.attrib.get('solutionName')
if sol_name:
new_mipstart_sol.set_name(sol_name)
# effort level: 0,1,2,...
effort_s = child.attrib.get('MIPStartEffortLevel')
if effort_s is not None:
# expect an integer attribute, then convert it to EffortLevel
# default is Auto
effort_level = EffortLevel.parse(cls.to_int(effort_s,
fallback=0),
fallback=EffortLevel.Auto)
elif child.tag == "variables":
for v, var_elt in enumerate(child, start=1):
var_attribs = var_elt.attrib
var_name = var_attribs.get('name')
var_value_s = var_attribs.get('value')
# check the <variable> taag
valid = True
# we need a value
var_value = cls.to_float(var_value_s)
if var_value is None:
mdl.warning(
"Variable element has no float value, {0} was found - pos={1}",
var_value_s, v)
valid = False
var_index = cls.to_int(var_attribs.get('index'))
if var_index is None:
mdl.warning(
"Variable element has no index tag - pos={0}", v)
valid = False
elif var_index < 0:
mdl.warning(
"Variable element has invalid index: {1} - pos={0}",
v, var_index)
valid = False
if not valid:
nb_missed += 1
else:
# look for a variable from name, index
dv = (var_name and mdl.get_var_by_name(var_name)
) or mdl.get_var_by_index(var_index)
if dv is None:
mdl.warning(
'Cannot find matching variable: name={0}, index={1} - value={2}',
var_name, var_index, var_value)
nb_missed += 1
else:
new_mipstart_sol._set_var_value(dv, var_value)
if nb_missed:
mdl.warning("Found {0} unmatched variable(s) in file {1}",
nb_missed, mst_path)
# return a tiple (solution, effort)
if not new_mipstart_sol.number_of_var_values:
mdl.warning("No variable read from MIP start file {0}", mst_path)
return None
else:
return new_mipstart_sol, effort_level
def print_one_solution(cls,
sol,
out,
print_header=True,
use_lp_names=True,
write_level=None,
effort_level=None):
osa = OutputStreamAdapter(out)
if print_header:
osa.write(cls.mst_header)
cls.print_signature(out, write_level)
# <CPLEXSolution version="1.0">
osa.write(cls.one_solution_start_tag)
osa.write("\n")
# <header
# problemName="foo"
# objectiveValue="42"
# />
osa.write(" <header\n problemName=\"{0}\"\n".format(
sol.problem_name))
if sol.has_objective():
osa.write(" objectiveValue=\"{0:g}\"\n".format(
sol.objective_value))
if effort_level is not None:
# assert this is an integer
eff = EffortLevel.parse(effort_level)
if eff != EffortLevel.Auto:
osa.write(" MIPStartEffortLevel=\"{0:d}\"\n".format(
eff.value))
osa.write(" />\n")
# <variables>
# <variable name="x1" index ="1" value="3.14"/>
# </variables>
osa.write(" <variables>\n")
"""
osa.write(" <variable name=\"{0}\" index=\"{1}\" value=\"{2:g}\" {3}/>\n"
.format(var_name, var_index, var_value, rc_string))
"""
print_generated = cls.print_generated_vars
filter_discrete = write_level.filter_discrete()
eps = 1e-16
if write_level.filter_zeros():
for dvar, _ in sol.iter_var_values():
if print_generated or not dvar.is_generated():
if not filter_discrete or dvar.is_discrete():
var_name = LPFormat.lp_var_name(
dvar) if use_lp_names else dvar.name
var_value = sol[dvar]
if abs(var_value) >= eps:
var_index = dvar.index
if var_name:
osa.write(
" <variable name=\"{0}\" index=\"{1}\" value=\"{2:g}\"/>\n"
.format(var_name, var_index, var_value))
else:
osa.write(
" <variable index=\"{1}\" value=\"{2:g}\"/>\n"
.format(var_name, var_index, var_value))
else:
# iterate on all variebls
for dvar in sol.model.generate_user_variables():
if (not filter_discrete) or dvar.is_discrete():
var_name = LPFormat.lp_var_name(
dvar) if use_lp_names else dvar.name
var_value = sol[dvar]
var_index = dvar.index
if var_name:
osa.write(
" <variable name=\"{0}\" index=\"{1}\" value=\"{2:g}\"/>\n"
.format(var_name, var_index, var_value))
else:
osa.write(
" <variable index=\"{1}\" value=\"{2:g}\"/>\n".
format(var_name, var_index, var_value))
osa.write(" </variables>\n")
# </CPLEXSolution version="1.0">
osa.write(cls.one_solution_end_tag)
osa.write("\n")