Error Implicit conversion of Pyomo NumericValue type

[Deepak Agrawal]

Hi, 

I am trying to create a range using pyomo parameter. Following is the code and I am getting following error

TypeError: Implicit conversion of Pyomo NumericValue type `floor' to an integer is
disabled. This error is often the result of using Pyomo components as
arguments to one of the Python built-in math module functions when
defining expressions. Avoid this error by using Pyomo-provided math
functions.

I know the reason of the error is because I am using range with pyomo model. What can I do to solve this?

sum([(x[kj, lj, ij] ** i) / prod(j for j in range(1, i)) for i in range(0, math.floor(model.gamma[kj] * model.cap[kj, lj]))])

Thank you very much in advance.

[David Woodruff]

Your trouble is the use of

math.floor(model.gamma[kj]

If gamma is a Param (or a Python variable), then you can compute the floor outside of this expression. If gamma is a Var, then you have a modeling problem: you will need to

create an integer Var that is constrained to be the floor of gamma.

Dave

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[Deepak Agrawal]

Hi, sorry I didn't clarify, both gamma and cap are Param.

Can you please explain how can I calculate floor outside this expression? I have written exactly what I am trying to do below.

def P1_rule(model, kj, lj, ij):
    return 1 - exp(-alpha_rule(model, kj, lj, ij) * sum([(alpha_rule(model, kj, lj, ij) ** i) / prod(j for j in range(1, i)) for i in range(0, floor(model.gamma[kj]*model.cap[kj,lj]))]))

I checked in my code, I can calculate floor(model.gamma[kj]*model.cap[kj,lj]), but I get error when I do range(floor(...))

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