[Scip] including a solution found by an heuristic

[Ambros Gleixner]

Hi Alessia,

this sounds strange and I also don't understand.  I can only recommend 
you to add more printf's to SCIPsolCheck() to trace down exactly where 
the feasible flag changes to FALSE.

Ambros



Am 19.06.2013 12:25, schrieb Alessia Violin:
> Hello,
>
> yes, the solution is for the transformed problem, and with the function
> SCIPgetSolTransObj(scip,sol) I get the correct value for the objective
> function in the transformed space, or with SCIPgetSolOrigObj(scip,sol)
> in the original space.
>
> I tried your suggestions:
> - adding #define SCIP_DEBUG to sol.c does not give any additional output
> - printing out the return of solOfInterest() in SCIPprimalTrySolFree()
> gives me TRUE. Then I tried to add another printf to check the value
> "feasible" after the call of SCIPsolCheck and I get FALSE, so I suppose
> the problem is here, but I don't understand as I don't get any printing
> of violating constraints/bounds etc and I checked that it's better than
> the current one and feasible.
>
> Thanks again,
>
> best,
>
> Alessia
>
>
>
>
> On 06/18/2013 05:37 PM, Ambros Gleixner wrote:
>> Hi Alessia,
>>
>> I suppose the solution lives in the transformed problem, does it?
>>
>> Maybe you can get some additional information if you add
>>
>> #define SCIP_DEBUG
>>
>> at the very top of src/scip/sol.c and recompile.  If not, you could
>> add a manual debug printf to SCIPprimalTrySolFree() in primal.c to see
>> whether solOfInterest() returns TRUE.
>>
>> Ambros
>>
>>
>>
>> Am 18.06.2013 16:59, schrieb Alessia Violin:
>>> Hello,
>>>
>>> I am trying to implement a simple heuristic into my branch-and-price,
>>> and I am having some troubles when adding the new solution found with
>>> the function SCIPtrySolFree(scip, &sol, TRUE, TRUE, TRUE, TRUE,
>>> &success).
>>>
>>> The "success" parameter after this call is always false, even if I don't
>>> get any violation of constraints/bounds etc printed out. I also manually
>>> checked the solution found by the heuristic, and it's feasible, not
>>> violating the branching constraints in the current node, and better that
>>> the current primal bound. So I don't know where/what to search more to
>>> avoid this and to make scip using this new solution...
>>>
>>> If needed I can of course provide more details on my implementation.
>>>
>>> Thanks in advance for any help,
>>>
>>> best,
>>>
>>> Alessia
>>>
>>
>