[petsc-users] return -1 instead of raising an error in ao.app2petsc

[Barry Smith]

  Hmm,

PetscErrorCode AOApplicationToPetsc_Basic(AO ao,PetscInt n,PetscInt *ia)

   has

    if (ia[i] >= 0 && ia[i] < N) {
      ia[i] = aobasic->petsc[ia[i]];
    } else {
      ia[i] = -1;
    }

PetscErrorCode AOApplicationToPetsc_Mapping(AO ao, PetscInt n, PetscInt *ia)

has 

    if (low > high) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE, "Invalid input index %D", idex);

PetscErrorCode AOApplicationToPetsc_MemoryScalable(AO ao,PetscInt n,PetscInt *ia)

has 

      if (ia[i] >= owners[rank] && ia[i] < owners[rank+1] ) {
        ia[i] = maploc[ia[i]-owners[rank]];
      } else {
        ia[i] = -1 ; /* ia[i] is not in the range of 0 and N-1, maps it to -1 */
      }

So it seems the intention is to return -1 for out of range not an error.

Can the PETSc developer who wrote all this stuff comment?   Likely our bug! Also we should fix the manual page for AOApplicationToPetsc() to clearly indicate what happens for out of range values

   Barry


On Aug 8, 2012, at 3:10 PM, Xin Zhao <sean.null at gmail.com> wrote:

> Dear all,
> 
> Assume that I want to convert an indices in application order into petsc order.
> But I don't know the indices in application is in range.
> 
> Say 
> I call
> ao = PETSc.AO().createMapping([4,2,3])
> 
> then
> ao.app2petsc([2,5,3])
> will raise an error.
> 
> is there any way to make return value to [1,-1,2] instead of raising an error?
> 
> 
> Or there is any way I can handle this error to make it work?
> 
> Best,
> Xin