I´m trying to optimize the transportation of a single product over several periods of time with PuLP in Python. I face a problem forming the objective function with it:
routes =[(t,i,j) for t in TIME for i in ORIGIN for j in DESTINATION]
amount_var = LpVariable.dicts('Volume', (TIME, ORIGIN, DESTINATION), lowBound=0, cat='Integer')
route_usage = LpVariable.dicts('route_usage', routes, cat='Binary')
Objective f-n:
model += LpProblem("Minimize costs", LpMinimize)
model+=lpSum(amount_[t][i][j]*price[t][i] for (t,i,j) in routes for t in TIME for i in ORIGIN)
price is a dictionary of tuple:integer couples like {(period1,origin1) : price1, (period2,origin1) : price2 etc.}.
Do You have an idea how to solve it?