[OS] multiple solutions

[Mike Steglich]

Hi Gus,


Thank you for your answer. It helps if one uses the OS libs. But is there also an opportunity to catch the incumbents by using OSSolverService/CBC and to write these solutions in <solution> sections? ( I have forgotten to write that I want to use the OSSolverService binary in my first email.)

Thanks,

Mike


Am 05.11.2012 um 20:35 schrieb Horand Gassmann:

> Mike Steglich <mike.steglich at berlin.de> wrote:
> 
>> Is it possible to write the incumbents found during an MIP optimization into a OSrL file?
> 
> Yes. :-)
> 
> There are several routes you might want to take. First, you can put multiple <solution> elements into the file. Each solution must have a status; you could use "bestSoFar" for the incumbent solutions.
> 
> Alternatively you might want to look at <other> elements that somehow code the incumbent solution appropriately. You'd need to choose your own name for the <other> elements, and I am not sure off-hand how you could capture the objective value in the same element. (But you could always compute that on the fly if needed.)
> 
> Or you can simply print out the incumbents in the solver, and capture the solver output in the <job> option. Our OSrL parser can put any of those versions into an in-memory OSResult object, although the interpretation of what the different things mean would be up to you --- at least at this point. Our current repository has an osol file, serverOutputCapture.osol, and an osrl file, serverOutputCapture.osrl, to illustrate.
> 
> Hope that helps.
> 
> gus
> 
>> Thanks,
>> 
>> Mike
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> 
> 
> 
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> 
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