[BCP] Never mind (Re: "BM: Couldn't branch!")

[Laszlo Ladanyi]

Phew, I just started to look into it :-).

Thanks for letting me know!

--Laci

On Fri, 5 Sep 2008, Eric W Anderson wrote:

> Never mind, it looks like this was a symptom of an unrelated problem that was
> causing memory corruption.
>
>
> Thus spake Eric W Anderson (Eric.Anderson at colorado.edu):
>
>> Another new-user question here:
>>
>> I have a simple application based on the SHELL example.  The problem is passed
>> in from Python using SWIG, and the results are passed back out the same way,
>> but otherwise it's pretty much taken straight from the example.
>>
>> It always runs fine on small MIPs, but when I give it a modest-sized one (~1500
>> binary vars), my application frequently dies with the error "BM: Couldn't
>> branch!".  Here's what I know:
>>
>>  *  This happens in from BCP_lp_user::select_branching_candidates(...),
>>     when try_to_branch(...) returns 0 and does not set branchObject.
>>
>>  *  That occurs when choose->setupList(&branchInfo, true) returns 0.  (choose
>>     is an OsiChooseVariable* pointing to an OsiChooseStrong).
>>
>>  *  I don't understand OsiChooseStrong, or the general operation of BCP well
>>     enough to know (a) why this is happening or (b) why it's a bad thing.
>>
>> Is this problem familiar to anyone?  Any suggestions?
>>
>> Thanks again,
>> Eric
>>
> -- 
> Eric W. Anderson                                   University of Colorado
> eric.anderson at colorado.edu                      Dept. of Computer Science
> phone: +1-720-984-8864                   Systems Research Lab - ECCR 1B54
>
>                         PGP key fingerprints:
>       personal: 1BD4 CFCE 8B59 8D6E EA3E  EBD5 4DC9 3E61 656C 462B
>       academic: D3C5 D6FF EDED 9F1F C36D  53A3 74B7 53A6 3C74 5F12
>