[Osi-tickets] [COIN-OR Open Solver Interface] #10: OsiClpSolverInterface::addCols

[COIN-OR Open Solver Interface]

#10: OsiClpSolverInterface::addCols
--------------------+-------------------------------------------------------
 Reporter:  San     |       Owner:  mjs
     Type:  defect  |      Status:  new
 Priority:  major   |   Milestone:     
Component:  OsiClp  |     Version:     
 Keywords:          |  
--------------------+-------------------------------------------------------
 Hi.  I'm just wondering if I'm using the following Osi correctly to
 add the columns.

 {{{
 void OsiClpSolverInterface::addCols(const int numcols,
                   const CoinPackedVectorBase * const * cols,
                   const double* collb, const double* colub,
                   const double* obj)
 }}}


 I don't want to add rows when I'm calling the addCols method, but when
 I pass NULL for the CoinPackedVectorBase parameter, it'll crash in


 {{{
 void CoinPackedMatrix::appendMajorVectors(const int numvecs,
                                    const CoinPackedVectorBase * const *
 vecs)
 {
  ...
  for (i = 0; i < numvecs; ++i)
    nz += CoinLengthWithExtra(vecs[i]->getNumElements(), extraGap_);
  ...
 }

 }}}
 as it is accessing vecs[i] without checking to see if vecs is not NULL.

 When I changed the addCols method to only append cols when the
 CoinPackedVectorBase is not NULL, it seemed to be working ok for small
 problems that I was testing.

 {{{
 void OsiClpSolverInterface::addCols(const int numcols,
                               const CoinPackedVectorBase * const * cols,
                               const double* collb, const double* colub,
                               const double* obj)
 {
  ...
  if (cols != NULL) // added this check so that it's only appending
 cols when it is specified
  {
      modelPtr_->matrix()->appendCols(numcols,cols);
  }
  ...
 }

 }}}

 If I don't change the Osi code and just pass in an array with:

 {{{
        CoinPackedVectorBase ** columns= new CoinPackedVectorBase*
 [numCol];
            for (unsigned int i = 0; i < numCol; i++)
            {
                columns[i] = new CoinPackedVector(0,static_cast<const
 int *>(NULL),static_cast<const double *>(NULL));
            }

 }}}
 it seems to be working ok, but I don't see why I have to do that when
 I could get the rest of the code working without appending any
 CoinPackedVectorBase.

 I'm just wondering if this was a bug or whether I've used the
 interface incorrectly.

 Thanks.
 San

-- 
Ticket URL: <https://projects.coin-or.org/Osi/ticket/10>
COIN-OR Open Solver Interface <https://projects.coin-or.org/Osi/>
The COIN-OR Open Solver Interface