[petsc-users] DaSetGetMatrix

[Barry Smith]

  Please send a complete error report with the entire error message to petsc-maint at mcs.anl.gov without the information we cannot even begin to guess what the issue is.

   Barry

On Apr 20, 2011, at 10:32 AM, domenico.borzacchiello at univ-st-etienne.fr wrote:

> Hi,
> 
> I'm running my code (3D Stokes Solver with MAC arrangement) pretty fine so
> far with a FieldSplit/Schur Preconditioning.
> 
> I had to write my own DAGetMatrix routine cause it was using too much
> memory (5 times the required size) for the matrices. The code works  with
> 1 2 3 5 etc procs (I presume with any number of procs for which are only
> possible 1D cartesian topologies of communicators i.e. any prime numbers) 
> then if I run with 4 procs for example it stops when assembling the MPIAIJ
> matrix with the following error:
> 
> [1]PETSC ERROR: Nonconforming object sizes!
> [1]PETSC ERROR: Local scatter sizes don't match!
> 
> What could be causing the error?
> 
> Thank you,
> Domenico
> 
> here's the getmatrix function I'm using
> 
> #undef __FUNCT__
> #define __FUNCT__ "DAGetMatrix_User_2"
> PetscErrorCode DAGetMatrix_User_2(DA da,const MatType mtype,Mat *J)
> {
>  PetscErrorCode ierr;
>  Mat A;
>  PetscInt xm,ym,zm,dim,dof,starts[3],dims[3];
>  const MatType  Atype;
>  void          
> (*aij)(void)=PETSC_NULL,(*baij)(void)=PETSC_NULL,(*sbaij)(void)=PETSC_NULL;
>  ISLocalToGlobalMapping ltog,ltogb;
> 
>  PetscFunctionBegin;
>  ierr = DAGetInfo(da,&dim, 0,0,0, 0,0,0,&dof,0,0,0);CHKERRQ(ierr);
>  if (dim != 3) SETERRQ(PETSC_ERR_ARG_WRONG,"Expected DA to be 3D");
> 
>  ierr = DAGetCorners(da,0,0,0,&zm,&ym,&xm);CHKERRQ(ierr);
>  ierr = DAGetISLocalToGlobalMapping(da,&ltog);CHKERRQ(ierr);
>  ierr = DAGetISLocalToGlobalMappingBlck(da,&ltogb);CHKERRQ(ierr);
>  ierr = MatCreate(((PetscObject)da)->comm,&A);CHKERRQ(ierr);
>  ierr =
> MatSetSizes(A,dof*xm*ym*zm,dof*xm*ym*zm,PETSC_DETERMINE,PETSC_DETERMINE);CHKERRQ(ierr);
>  ierr = MatSetType(A,mtype);CHKERRQ(ierr);
>  ierr = MatSetFromOptions(A);CHKERRQ(ierr);
>  ierr = MatSeqAIJSetPreallocation(A,17,PETSC_NULL);CHKERRQ(ierr);
>  ierr =
> MatMPIAIJSetPreallocation(A,17,PETSC_NULL,12,PETSC_NULL);CHKERRQ(ierr);
>  ierr = MatSeqBAIJSetPreallocation(A,dof,7,PETSC_NULL);CHKERRQ(ierr);
>  ierr =
> MatMPIBAIJSetPreallocation(A,dof,7,PETSC_NULL,0,PETSC_NULL);CHKERRQ(ierr);
>  ierr = MatSeqSBAIJSetPreallocation(A,dof,4,PETSC_NULL);CHKERRQ(ierr);
>  ierr =
> MatMPISBAIJSetPreallocation(A,dof,4,PETSC_NULL,0,PETSC_NULL);CHKERRQ(ierr);
>  ierr = MatSetDA(A,da);
>  ierr = MatSetFromOptions(A);
>  ierr = MatGetType(A,&Atype);
>  ierr = MatSetBlockSize(A,dof);CHKERRQ(ierr);
>  ierr = MatSetLocalToGlobalMapping(A,ltog);CHKERRQ(ierr);
>  ierr = MatSetLocalToGlobalMappingBlock(A,ltogb);CHKERRQ(ierr);
>  ierr =
> DAGetGhostCorners(da,&starts[0],&starts[1],&starts[2],&dims[0],&dims[1],&dims[2]);CHKERRQ(ierr);
>  ierr = MatSetStencil(A,dim,dims,starts,dof);CHKERRQ(ierr);
>  *J = A;
>  PetscFunctionReturn(0);
> }
>