[Coin-discuss] sbb/resolve a MIP?

[Tuomo Takkula]

On 9 Jun 2004 at 14:19, John J Forrest wrote:

> 
> 
> I think it would need a major re-write of Sbb. On the other hand it
> would be fairly easy to provide callbacks which might allow more
> flexibility along the lines of ClpEventHandler. One could collect
> maximum nodes, solutions, seconds etc into SbbEventHandler and then
> let the user derive a class from this which could do whatever is
> wanted and then reset the maximum value. 
> 
> If you can describe what you want to do or send me something I can see
> how much work it would be. 

Simply speaking, I'd like to have some way to tell the brand-and-
bound solver to run until it finds the first feasible solution, and 
then for a specified time more. 

Additional nice-to-have features could be:

* besides the "soft" time limit mentioned above, some "hard" time 
limit for when to abort for good even if no feasible solution was 
found

* at the callback to have the possibility to fix some variables 
before the solver is resumed

* at the callback to have the possibility to change some parameters 
that would affect the branch-and-bound solver "from now on" (I've got 
no clue how realistic this is) and resume

* access to the best solution so far at callback.
> 
> John Forrest 
> 
> If you can send me 
> 
[somehow the rest of this never arrived at me]


	Best regards and thanks for the quick answer
	Tuomo Takkula

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Tuomo Takkula, PhD
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