> On Nov 30, 2018, at 1:30 PM, Sajid Ali via petsc-users > <[email protected]> wrote: > > Hi, > > I tried running ex19.c and I get the following error (I added a small snippet > to print the local size on rank0 as well) : > > [sajid@xrm temp]$ mpirun -np 2 ./ex19 > local_sizes : 3 4 > [1]PETSC ERROR: --------------------- Error Message > -------------------------------------------------------------- > [1]PETSC ERROR: Arguments are incompatible > [1]PETSC ERROR: Incompatible vector local lengths parameter # 1 local size 3 > != parameter # 2 local size 2 > [1]PETSC ERROR: See http://www.mcs.anl.gov/petsc/documentation/faq.html for > trouble shooting. > [1]PETSC ERROR: Petsc Release Version 3.10.2, unknown > [1]PETSC ERROR: ./ex19 on a named xrm by sajid Fri Nov 30 13:28:36 2018 > [1]PETSC ERROR: [0]PETSC ERROR: --------------------- Error Message > -------------------------------------------------------------- > [0]PETSC ERROR: Arguments are incompatible > [0]PETSC ERROR: Incompatible vector local lengths parameter # 1 local size 3 > != parameter # 2 local size 4 > [0]PETSC ERROR: See http://www.mcs.anl.gov/petsc/documentation/faq.html for > trouble shooting. > [0]PETSC ERROR: Petsc Release Version 3.10.2, unknown > [0]PETSC ERROR: ./ex19 on a named xrm by sajid Fri Nov 30 13:28:36 2018 > > Does this mean that PETSC_DECIDE is inconsistent between two calls in the > same file ?
No. The reason for the error is a bug in the code. The x1 vector has a block
size of 1 hence when it is divided among two processes it gets 3 entries on
each process. The x2 vector has a block size of 2 so when it is divided among
two processes it gets 4 entries on the first process and 2 on the second. The
call to VecCopy() does not work because the two vectors have different layouts.
I have attached a fixed version of the code (that does not copy from x1 to
x2).
Barry
>
> Thank You,
> Sajid Ali
> Applied Physics
> Northwestern University
ex19.c
Description: ex19.c
