Questions tagged [scip]
SCIP is a source-open solver for (among others) MILPs, MINLPs, ... ask questions about usage, bugs, interfaces, behavior.
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SoPlex basis file format
I'm running SoPlex from the command line to solve some linear programming problems. I'd like to get the basis of the solution, so I use the --writebas flag. However,...
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Changing a parameter while branching in SCIP
I use pyscipopt. I know how to add constraints while branching using handlers (kind of), but now I want also to change some parameters. I imagine is similar, but couldn’t found an example.
What I want ...
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Using Neural Networks For Solving Optimization Problems
Recently, I came across the below paper and found it very interesting.
Solving Mixed Integer Programs Using Neural Networks; https://arxiv.org/abs/2012.13349
The idea is to use (train with neural ...
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Importing data into SCIP solver
Is it possible to import data into SCIP from Excel (and then export results to Excel)? If yes, how can I do it?
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Doesn't Pyscipopt handle nonlinear objective functions?
I am trying to solve a large-scale nonlinear problem. Below is the objective function coded for pyscipopt. I have some loops over a list of tuples (r,p,s) in the list RouteTimeStop, and the only ...
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Can I use 'SCIP' solver for PYOMO?
I have an MINLP problem to solve where I was initially using 'ipopt' solver but the solution was not sticking to 'binary/boolean/integer' domain type for a variable. I am not sure which free solver ...
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Branch-and-Price: return gap using SCIP
I implemented a branch-and-price tree in python.
I would like to stop the process after 5 hours and return the gap in % between the best integer solution found so far and the optimal solution.
How ...
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Warm-start SCIP with a solution
I am trying to solve a MIP using SCIP. I let my solver run for some initial time-bound - let's say 10min. After 10min, I check if the problem is solved to optimality or 1% gap. If not, then I would ...
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Column generation stabilisation
Has anyone performed a benchmark of the various stabilisation techniques in column generation? Which ones perform better for set pack/partition/cover problems like VRP? And are there theoretical ...
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