Questions tagged [cutting-planes]
The cutting-planes tag has no usage guidance.
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Julia JuMP successive optimization
I am using Julia's JuMP package to solve a cutting-plane method. Namely, I solve a sub-problem, find the most-violated constraint in the master problem, add that to ...
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When and where the cutting plane method should be applied?
As the cutting plan algorithm is a method to strengthen the feasible space of the linear programming, specifically in the MILP problems to invoke the integer solutions, it may be a problem-based ...
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Exploiting ordering to removing infeasible solutions in MILP
I kindly ask for some ideas or references to exploit ordering in MILPs.
In particular, there are resources $ r = [r_1, r_2, ..., r_K] $ such that $r_{i} \leq r_{i+1} $. These are input to the problem.
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How to redefine separation procedure to get 0-1 knapsack with odd number of items
So I have a 0-1 knapsack problem:
\begin{align}\max&\quad \sum_j c_j x_j\\
\text{s.t.}&\quad \sum_j a_j x_j \leq b\\
&\quad x_j \in \{0,1\}\end{align}
but it has an additional requirement ...
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A specific case of a resource constrained project scheduling problem with partially renewable resources (RCPSP/$\pi$) - OR-Tools
I've been trying solve a specific case of the resource constrained project scheduling problem with partially renewable resources (RCPSP/$\pi$ in the literature e.g. this paper). These resources are ...
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How to implement CPLEX user cuts using CPXaddusercuts in C API?
I am trying to use CPXaddusercuts to add cutting planes, which have not been violated yet but are likely to be violated as we go down the branch & bound tree, to the list (pool) of constraints. As ...
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Objective Integrality Cuts
Consider a mixed integer linear program with an objective function that includes only integer variables. Objective integrality cuts are known as a class of valid inequalities that can be added to ...
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Cplex : The cutting stock problem
The problem below aims to minimize the cutting leftovers from each cut :
A company manufactures desks for kids gardens and primary schools, colleges and high schools. The leg of these deks all have ...
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Cutting-planes application procedure for a specific problem
Sort of following up with this question. I reformulated another model to make it convex and possibly solve it with some cut generation method. I would like to double-check whether I am doing it ...
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Improving cuts from sub-problem with problem-specific hierarchical information
I'm solving an assignment-alike problem with a Logic-based Benders decomposition-alike (LBBD) method. The master problem provides an assignment, which is checked in the sub-problem.
Define the set of ...
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Why isn't $x_2+x_3+x_4\le 2$ a cutting plane?
In my textbook, to generate cutting planes, they tell you to proceed as follows:
A procedure for generating cutting planes:
Select a ($\le$) constraint that has only nonnegative coefficients.
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What to do with cuts (constraints) when a fixation is contrary to a RHS in a ILP / LP relaxation?
I am trying to understand an algorithm in a paper by Crévits et al. (2012)1 (see algorithm 2, the cuts I'm referring to are from the reduced costs). It uses a series of successive cuts on a linear ...
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Family of hard instances for Gomory's cutting plane algorithm
Is there a variant of integer programs for which Gomory's cutting plane algorithm demonstrably takes a superpolynomial number of iterations?