def assign_sections(tas, prioritize=False, analyze=False):
"""
tas: a list of ta objects
i = index of sections
j = index of tas
The columns, x_i_j, go as follows:
x_0_0, x_1_0, x_2_0, ..., x_0_1, ..., x_M_N
"""
M = len(tas[0].rankings) # number of section
N = len(tas) # number of tas
f = make_obj_f(tas, prioritize)
A = make_coeff_m(M, N)
b = make_b_v(tas, M, N)
e = make_e_v(M, N)
v = [1 for _ in range(M*N)]
lp = lpm.lp_maker(f, A, b, e, None, v)
# set branch and bound depth
lps.lpsolve('set_bb_depthlimit', lp, 0)
# set all variables to binary
lps.lpsolve('set_binary', lp, v)
# set lp to minimize the objective function
lps.lpsolve('set_minim', lp)
lps.lpsolve('write_lp', lp, LP_OUT)
lps.lpsolve('solve', lp)
res = lps.lpsolve('get_variables', lp)[0]
lps.lpsolve('delete_lp', lp)
parse_results(res, tas, M, analyze)
def assign_sections(students, prioritize=False, debug=False):
"""
students: a list of student objects
i = index of sections
j = index of students
The columns, x_i_j, go as follows:
x_0_0, x_1_0, x_2_0, ..., x_0_1, ..., x_M_N
"""
M = len(students[0].rankings) # number of section
N = len(students) # number of students
f = make_obj_f(students, prioritize)
A = make_coeff_m(M, N)
b = make_b_v(students, M, N)
e = make_e_v(M, N)
v = [1 for _ in range(M * N)]
lp = lpm.lp_maker(f, A, b, e, None, v)
# set branch and bound depth to be unlimited
lps.lpsolve("set_bb_depthlimit", lp, 0)
# set all variables to binary
lps.lpsolve("set_binary", lp, v)
# set lp to minimize the objective function
lps.lpsolve("set_minim", lp)
lps.lpsolve("write_lp", lp, LP_OUT)
lps.lpsolve("solve", lp)
res = lps.lpsolve("get_variables", lp)[0]
lps.lpsolve("delete_lp", lp)
parse_results(res, students, M, debug)
def get_lpsolve_handler(self, maxNameLength=255, startIndex=0):
try: from lp_maker import lp_maker, lpsolve
except ImportError: self.err('To export LP/MILP in files you should have lpsolve and its Python binding properly installed')
self._Prepare()
from ooMisc import LinConst2WholeRepr
LinConst2WholeRepr(self)
# set goal to min/max
minim = 0 if self.goal in ['max', 'maximum'] else 1
# objective
f = self._init_f_vector
lp_handle = lp_maker(List(asarray(f).flatten()), List(self.Awhole), List(asarray(self.bwhole).flatten()), List(asarray(self.dwhole).flatten()), \
List(self.lb), List(self.ub), (1+asarray(self._intVars_vector)).tolist(), 0,minim)
#lp_handle = lpsolve('make_lp', len(self.beq)+len(self.b), self.n)
L = lambda action, *args: lpsolve(action, lp_handle, *args)
# set name
L('set_lp_name', self.name)
# set boolean values if present
#if len(self.boolVars)>0:
#assert self.boolVars[0] in [True, False]
#L('set_binary', self.boolVars)
# set variables names
if self.isFDmodel:
assert not isinstance(self.freeVars, set), 'error in openopt kernel, inform developers'
#assert len(self.freeVars) == self.n, 'not implemented yet for oovars of size > 1'
#names = [oov.name for oov in self.freeVars]
x0 = self._x0
names = []
#assert not isinstance(self.freeVars, set), 'error in openopt kernel, inform developers'
for oov in self.freeVars:
if oov.name.startswith('unnamed'):
L('delete_lp')
self.err('For exporting FuncDesigner models into MPS files you cannot have variables with names starting with "unnamed"')
if ' ' in oov.name:
L('delete_lp')
self.err('For exporting FuncDesigner models into MPS files you cannot have variables with spaces in names')
Size = asarray(x0[oov]).size
if Size == 1:
Name = oov.name
names.append(Name)
else:
tmp = [(oov.name + ('_%d' % (startIndex+j))) for j in range(Size)]
names += tmp
Name = tmp[-1]
if maxNameLength < len(Name):
L('delete_lp')
self.err('incorrect name "%s" - for exporting FuncDesigner models into MPS files you cannot have variables with names of length > maxNameLength=%d'% maxNameLength)
# TODO: check are names unique
L('set_col_name', names)
return lp_handle
def assign_placements():
num_tas = len(all_tas)
num_times = len(ID_TO_TIMES)
upper = [1 for _ in range(num_tas * num_times)] # max value must be 1
obj_func = make_obj_func()
constr_mat = make_constr_mat(num_tas, num_times)
b_vector = make_b_vector()
e_vector = make_e_vector(num_tas, num_times)
lp = lpm.lp_maker(obj_func, constr_mat, b_vector, e_vector)
lps.lpsolve('set_bb_depthlimit', lp, 0) # set branch and bound depth limit
lps.lpsolve('set_binary', lp, upper) # all values must be either 0 or 1
lps.lpsolve('solve', lp)
vars = lps.lpsolve('get_variables', lp)[0]
lps.lpsolve('delete_lp', lp)
output_results(vars)
def solve_linprog(c, A_ub, b_ub, A_eq, b_eq, bounds):
"""
solve a integer linear program either using scipy's Simplex algorithm
or the external library lpsolve
"""
try:
# use lpsolve
from lp_maker import lp_maker, lpsolve
# convert to format expected by lpsolve
c = c.astype(int).tolist() # c.x is the linear objective function
a = np.vstack((A_eq, A_ub)).astype(int).tolist(
) # matrix which contains both equality and inequality constraints, A_eq.x == b_eq, A_ub.x <= b_ub
b = np.hstack((b_eq, b_ub)).astype(int).tolist(
) # right hand side of equality and inequality constraints
e = np.hstack(([0 for bi in b_eq], [-1 for bi in b_ub])).tolist()
nvars = len(b_eq) + len(b_ub) # number of integer variables xi
xint = [i for i in range(1, nvars + 1)]
vlb = [bound[0] for bound in bounds]
vub = [bound[1] for bound in bounds]
# build lpsolve object
lp = lp_maker(c, a, b, e, vlb, vub, xint)
lpsolve('solve', lp)
lpsolve('get_objective', lp)
X = lpsolve('get_variables', lp)[0]
lpsolve('delete_lp', lp)
return X
except ImportError as e:
# use scipy's linprog
res = optimize.linprog(c,
A_ub=A_ub,
b_ub=b_ub,
A_eq=A_eq,
b_eq=b_eq,
bounds=bounds,
options={
"maxiter": 10000000,
"disp": True
})
X = res.x
print(
"WARNING: simplex algorithm may not respect integer constraints! Some bond orders may not be integers."
)
return X
def assign_placements():
"""
Takes in an option for which to assign placements for.
Outputs nothing, but calls output_results which prints all placements.
"""
num_tutors = len(all_tutors)
num_times = len(ID_TO_TIMES)
upper = [1 for _ in range(num_tutors * num_times)] # max value must be 1
obj_func = make_obj_func()
constr_mat = make_constr_mat(num_tutors, num_times)
b_vector = make_b_vector()
e_vector = make_e_vector(num_tutors, num_times)
lp = lpm.lp_maker(obj_func, constr_mat, b_vector, e_vector)
lps.lpsolve('set_bb_depthlimit', lp, 0) # set branch and bound depth limit
lps.lpsolve('set_binary', lp, upper) # all values must be either 0 or 1
lps.lpsolve('solve', lp)
vars = lps.lpsolve('get_variables', lp)[0]
lps.lpsolve('delete_lp', lp)
output_results(vars)
def get_lpsolve_handler(self, maxNameLength=255, startIndex=0):
try:
from lp_maker import lp_maker, lpsolve
except ImportError:
self.err(
'To export LP/MILP in files you should have lpsolve and its Python binding properly installed'
)
self._Prepare()
from ooMisc import LinConst2WholeRepr
LinConst2WholeRepr(self)
# set goal to min/max
minim = 0 if self.goal in ['max', 'maximum'] else 1
# objective
f = self._init_f_vector
lp_handle = lp_maker(List(asarray(f).flatten()), List(self.Awhole), List(asarray(self.bwhole).flatten()), List(asarray(self.dwhole).flatten()), \
List(self.lb), List(self.ub), (1+asarray(self._intVars_vector)).tolist(), 0,minim)
#lp_handle = lpsolve('make_lp', len(self.beq)+len(self.b), self.n)
L = lambda action, *args: lpsolve(action, lp_handle, *args)
# set name
L('set_lp_name', self.name)
# set boolean values if present
#if len(self.boolVars)>0:
#assert self.boolVars[0] in [True, False]
#L('set_binary', self.boolVars)
# set variables names
if self.isFDmodel:
assert not isinstance(
self.freeVars,
set), 'error in openopt kernel, inform developers'
#assert len(self.freeVars) == self.n, 'not implemented yet for oovars of size > 1'
#names = [oov.name for oov in self.freeVars]
x0 = self._x0
names = []
#assert not isinstance(self.freeVars, set), 'error in openopt kernel, inform developers'
for oov in self.freeVars:
if oov.name.startswith('unnamed'):
L('delete_lp')
self.err(
'For exporting FuncDesigner models into MPS files you cannot have variables with names starting with "unnamed"'
)
if ' ' in oov.name:
L('delete_lp')
self.err(
'For exporting FuncDesigner models into MPS files you cannot have variables with spaces in names'
)
Size = asarray(x0[oov]).size
if Size == 1:
Name = oov.name
names.append(Name)
else:
tmp = [(oov.name + ('_%d' % (startIndex + j)))
for j in range(Size)]
names += tmp
Name = tmp[-1]
if maxNameLength < len(Name):
L('delete_lp')
self.err(
'incorrect name "%s" - for exporting FuncDesigner models into MPS files you cannot have variables with names of length > maxNameLength=%d'
% maxNameLength)
# TODO: check are names unique
L('set_col_name', names)
return lp_handle