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pythonmodelpyomo

Set declaration in pyomo with tuples as key

begginer to pyomo I'm having a hard time to fully understand the set declaration of pyomo. Here's my code:

D = [1,2]
S = ['E', 'L', 'D', 'N']
CoverRequirement =  {(1, 'E'): 2,
 (1, 'L'): 2,
 (1, 'D'): 1,
 (1, 'N'): 1,
 (2, 'E'): 2,
 (2, 'L'): 1,
 (2, 'D'): 1,
 (2, 'N'): 2}

model.S = Set(initialize = S)
model.D = Set(initialize = D)
model.D_S = model.D_S = Set(within = model.D * model.S,
               initialize = [(d, s) for d in model.D for s in model.S])

model.CoverRequirement = Set(model.D_S, initialize = CoverRequirement)

Error:

ERROR: Initializer for Set R[(1, 'E')] returned non-iterable object of type
    int.
ERROR: Constructing component 'R' from data=None failed: TypeError: 'int'
    object is not iterable

The set R is the numbered of required employees at day d and shift s

I have tried things like this but it does not look correct:

model.CoverRquirement = Set(model.D_S, initialize = [((d,s),r) for (d,s) in R for r in R[r]])

How to declare my set cover requirement with d & s as index ? Thank you

Solution

  • Gor my answer, should have declare my input cover requierement using Param and not Set:

    model.R1 = Param(model.D_S, initialize = R)