[Scip] Accessing basis information of a node LP

[Ambros Gleixner]

Hi Matthias,

thanks for your question. The correct way are by using the public methods

SCIP_BASESTAT SCIPcolGetBasisStatus(SCIP_COL* col)
SCIP_BASESTAT SCIProwGetBasisStatus(SCIP_COL* row)

from src/scip/pub_lp.h, which will return one of

SCIP_BASESTAT_{LOWER,UPPER,BASIC,ZERO}

There is no public method to access the entire basis, but the above 
methods are inlined, i.e., very fast. The information is, of course, 
only valid if SCIPgetLPSolstat(scip) == SCIP_LPSOLSTAT_OPTIMAL and 
SCIPisLPSolBasic(scip) == TRUE. For columns which are not in the LP, 
SCIP_BASESTAT_ZERO is returned. For rows not in the LP, 
SCIP_BASESTAT_BASIC is returned.

ambros




Am 17.10.2011 08:11, schrieb Matthias Walter:
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> Hi everybody,
>
> I'd like to get the basis information for the current node in a
> LPsolved-event-handler. I know that one way is via
>
> SCIPgetLPI() followed by SCIPlpiGetState() (or SCIPlpigetBase()).
>
> What I expected is a method to obtain it without using the LPI methods,
> but with a SCIPgetLP* call. Is there such a functionality or a
> completely different way?
>
> Thank you!
>
> Matthias
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