Re: [petsc-users] How to view petsc array?

[TAY wee-beng]

On 21/7/2015 7:28 PM, Matthew Knepley wrote:
On Tue, Jul 21, 2015 at 1:35 AM, TAY wee-beng <zon...@gmail.com 
<mailto:zon...@gmail.com>> wrote:

    Hi,

    I need to check the contents of the array which was declared using:

    PetscScalar,pointer ::
    u_array(:,:,:),v_array(:,:,:),w_array(:,:,:),p_array(:,:,:)

    I tried to use :

    call PetscViewerASCIIOpen(MPI_COMM_WORLD,"pres.txt",viewer,ierr)

    call VecView(p_array,viewer,ierr)

    or

    call MatView(p_array,viewer,ierr)

    call PetscViewerDestroy(viewer,ierr)

    but I got segmentation error. So is there a PETSc routine I can use?


No. Those routines work only for Vec objects. You could

 a) Declare a DMDA of the same size

 b) Use DMDAVecGetArrayF90() to get out the multidimensional array

 c) Use that in your code

 d) Use VecView() on the original vector

Hi,

Supposed I need to check the contents of the u_array which was declared 
using:

PetscScalar,pointer :: u_array(:,:,:)

call 
DMDACreate3d(MPI_COMM_WORLD,DM_BOUNDARY_NONE,DM_BOUNDARY_NONE,DM_BOUNDARY_NONE,DMDA_STENCIL_STAR,size_x,size_y,&

size_z,1,PETSC_DECIDE,PETSC_DECIDE,1,stencil_width,lx,PETSC_NULL_INTEGER,PETSC_NULL_INTEGER,da_u,ierr)

call DMDAVecGetArrayF90(da_u,u_local,u_array,ierr)

call PetscViewerASCIIOpen(MPI_COMM_WORLD,"u.txt",viewer,ierr)

call VecView(array,viewer,ierr)

call PetscViewerDestroy(viewer,ierr)

Is this the correct way?

   Matt


    -- 
    Thank you

    Yours sincerely,

    TAY wee-beng




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