Python Pulp using with Matrices

Question

I am still very new to Python, after years and years of Matlab. I am trying to use Pulp to set up an integer linear program.

Given an array of numbers:

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Answer 1

You can set the lowBound and upBound on variables after the initialization. You can create an array of variables with

LB[i] <= x[i] <= UB[i]

with the following code.

x = pulp.LpVariable.dicts("x", RANGE,  cat="Integer")
for i in x.viewkeys():
     x[i].lowBound = LB_ind[i]
     x[i].upBound = UB_ind[i]

The second parameter to LpVariable.dict is the index set of the decision variables, not their lower bounds.

Answer 2

For the first question, you can do it like this in some other problem.

students = range(96)
group = range(24)

var = lp.LpVariable.dicts("if_i_in_group_j", ((i, j) for i in students for j in group),cat='binary')