def find_solution(function, bounds_array, optimal_model):
"""
Поиск решения симплек-методом
:param optimal_model: True — MAX / False — MIN
:param function: Функция
:param bounds_array: Условия
:return: Решение симплекс-методом
"""
max_num_of_func = Parser.find_max_constant(function)
max_num_of_bounds = Parser.find_max_constant(bounds_array)
num_of_const = max_num_of_func if max_num_of_func > max_num_of_bounds else max_num_of_bounds
x = [
LpVariable("x" + str(i + 1), lowBound=0)
for i in range(num_of_const)
]
problem = LpProblem("0", LpMaximize) if optimal_model else LpProblem(
"0", LpMinimize)
# Считаем main функцию
fun_cof = Parser.parse_alone_function(function, num_of_const)
problem += sum([fun_cof[i] * x[i] for i in range(num_of_const)])
coefficients = []
arguments = []
borders = []
# Считаем коэфициенты
for bound in bounds_array:
cof_arr, free_arr, border = Parser.parse_function_with_borders(
bound, num_of_const)
# Запоминаем всю информацию о начальных условиях для дальнейшей проверки
coefficients.append(cof_arr)
arguments.append(free_arr)
borders.append(border)
if border == Parser.MORE_OR_EQUAL:
problem += \
sum([cof_arr[0][i] * x[i] for i in range(num_of_const)]) + (
0 if free_arr[0] is None else free_arr[0]) >= \
sum([cof_arr[1][i] * x[i] for i in range(num_of_const)]) + (
0 if free_arr[1] is None else free_arr[1])
elif border == Parser.LESS_OR_EQUAL:
problem += \
sum([cof_arr[0][i] * x[i] for i in range(num_of_const)]) + (
0 if free_arr[0] is None else free_arr[0]) <= \
sum([cof_arr[1][i] * x[i] for i in range(num_of_const)]) + (
0 if free_arr[1] is None else free_arr[1])
elif border == Parser.EQUAL:
problem += \
sum([cof_arr[0][i] * x[i] for i in range(num_of_const)]) + (
0 if free_arr[0] is None else free_arr[0]) == \
sum([cof_arr[1][i] * x[i] for i in range(num_of_const)]) + (
0 if free_arr[1] is None else free_arr[1])
problem.solve()
variables = [var.varValue for var in problem.variables()]
if SimplexMethodSolver.__check_to_normal(coefficients, arguments,
borders, variables):
return problem.objective.value(), variables
return None, []
def test_max_arg_num(self):
functions = [
"-3x1 + x2 + 4x3", "-x2 + x3 + x4 = 1", "-5x1 + x2 + x3 = 2",
"-8x1 + x2 + 2x3 - x5 = 3"
]
self.assertEqual(5, Parser.find_max_constant(functions))