Unanswered Questions
862 questions with no upvoted or accepted answers
0
votes
1
answer
259
views
GAMS summing over subset
I am trying to sum over a subset between $t+1$ and $t+U-1$ as follows $$y_i^t+\sum_{k=t+1}^{t+Ut_i-1}z_i^k\le1$$ but I could not define the condition within sum.
...
-1
votes
1
answer
74
views
How to linearize a product of an integer and a binary variable
i have this constraint right here, which is not linear. How would i linearize such a product. $number_t$ is a positive integer and $new_t$ and $reset_t$ are binary.
$$number_t = (number_{t-1}+new_t)\...
-1
votes
1
answer
89
views
How do I translate the following constraint for gurobi py?
I successfully worked on the problem with following model in Excel, but I have a problem translating it into Python.
This is the proposed way to code the problem form the book:
...
-1
votes
1
answer
224
views
creating individual Variables in pyomo with different length
I am new to pyomo and I do have some smaller (or bigger) problems and hope someone can help me. How can you create this variable in pyomo? I wanted to create it with pyo.Varlist() in which I pass ...
-1
votes
1
answer
303
views
[OR-Tools][CP-SAT] Implement an indicator function in a constraint
Good morning ! I would like to implement this constraint using CP-SAT (see image below).
x_i,j is a boolean variable, a and b are given. The problem is that I don't know how to implement the ...
-1
votes
2
answers
153
views
Reformulate this constraint optimization problem such that I do not have to divide 2 variables?
I have a constraint optimization problem as follows:
I need to assign $m$ tasks to $n$ days, with $n \geq m$.
Each day can host 0 to $m$ tasks.
Each task either belongs to type $A$ or $B$.
I want to ...
-1
votes
1
answer
544
views
How to interpret velocity computation in Particle Swarm Optimization?
Please in PSO metaheuristic when we calculate the velocity what is the advantage of using pBest?