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### How to Speed Up the subgradient optimization procedure in a Lagrangian Relaxation Scheme

I'm currently working on the following problem (a variant of maximal k-covering problem): \begin{align} \max&\quad z =\sum\limits_{\omega\in \Omega}x_{\omega} \label{imbip3a} \\ \text{s.t.}&\...
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### When using column generation, can a sub-problem be ignored once and for all once it fails to generate a new column?

Suppose you are solving a minimization problem with a column generation procedure, and that you have $2$ sub-problems. At some point, one of the $2$ sub-problems is no longer able to generate a column ...
406 views

### Modelling an if-then-else logic in MIP

I was hoping to get some help in modelling the following logic as an MIP Constraint If $X_{ij}=1$ and $\text{SDV}_{ikj}=1$ for a particular index $i$, then $\text{SOC}^L_i=100$, else $\text{SOC}^L_i$...
356 views

### CPLEX, number of threads and solving time

Using CPLEX via its Python API, I encountered a "weird" behavior. For some instances, with a limited number of threads (10 in my tests), the instances cannot be solved after 10 days (afterwards, the ...
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### Check which constraints are violated (Concert - Cplex Studio 12.10 - C++)

Currently, I am working on the implementation of a formulation for an optimization problem, at the moment I already have the MIP formulation implemented in C++ using Cplex studio 12.10 with the ...
273 views

### Open Source MILP software for Python with user-friendly API to define the optimization problem

Following the accepted answer to Assignment problem where assignments must be done sequentially I would like to write a Python script which can solve the problem defined there. It's a Mixed Integer ...
59 views