[Scip] maxstallrounds question

[James Cussens]

Dear Gerald,

OK, this make a lot more sense and is indeed what I need. What was
throwing me were the invisible tolerances.
I have now found the magic numbers in solve.c. Is there an argument
for making these user-settable
parameters?

Many thanks,

James

On 24 October 2014 10:56, Gerald Gamrath <gamrath at zib.de> wrote:
> Dear James,
>
> a separation round is SCIP is counted as stalling, if from the last LP
> solution to the LP solution with cuts of this separation round added
> 1) the LP value (dual bound) did not improve and
> 2) the number of fractional variables did not reduce.
>
> For both these criterions, some tolerances are used, but this is the general
> idea.
>
> So the stalling has nothing to do with whether new primal solutions were
> found, but is actually very connected to the dual bound improvement.
> Therefore, I would recommend to use the maxstallrounds parameter in your
> case.
>



-- 
James Cussens
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York Centre for Complex Systems Analysis
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