[petsc-users] Expecting Explanation

[Smith, Barry F.]

   Then use

     ${PETSC_DIR}/${PETSC_ARCH}/bin/mpiexec 

  don't just use the random (wrong) mpiexec that is in your path.

   Barry


> On Nov 17, 2018, at 5:22 PM, Fazlul Huq <huq2090 at gmail.com> wrote:
> 
> I think when I have installed PETSc, I did --download-mpich.
> How can I correct it? Shall I install PETSc again?
> 
> Thanks.
> Sincerely,
> Huq
> 
> On Sat, Nov 17, 2018 at 4:53 PM Smith, Barry F. <bsmith at mcs.anl.gov> wrote:
> 
> 
> > On Nov 17, 2018, at 3:51 PM, Fazlul Huq via petsc-users <petsc-users at mcs.anl.gov> wrote:
> > 
> > Thanks for the answer.
> > 
> > So, when I run the code with "mpiexec -n 2 ./ex6" or "mpiexec -n 4 ./ex6" shouldn't it spit out 
> > the error "This is a uniprocessor example only!"? 
> > But it didn't do that rather run the code 2/4 times.
> 
>    This can happen if you use the "wrong" mpiexec; that is a different mpiexec than the one associated with the mpi you built PETSc with. For example if some mpiexec is in your path and you used ./configure --download-mpich
> 
>    Barry
> 
> 
> > 
> > Thanks.
> > Sincerely,
> > Huq
> > 
> > On Sat, Nov 17, 2018 at 1:12 PM Fazlul Huq <huq2090 at gmail.com> wrote:
> > Hello PETSc developers,
> > 
> > In example 6 or vec section I don't understand this line:
> > if (size != 1) SETERRQ(PETSC_COMM_SELF,1,"This is a uniprocessor example only!");
> > 
> > I tried to run the code with "mpiexec -n 2 ./ex6" or "mpiexec -n 4 ./ex6" or even "mpiexec -n 1 ./ex6" it the code runs properly.
> > 
> > Thanks.
> > 
> > Sincerely,
> > Huq
> > 
> > -- 
> > 
> > Fazlul Huq
> > Graduate Research Assistant
> > Department of Nuclear, Plasma & Radiological Engineering (NPRE)
> > University of Illinois at Urbana-Champaign (UIUC)
> > E-mail: huq2090 at gmail.com
> > 
> > 
> > -- 
> > 
> > Fazlul Huq
> > Graduate Research Assistant
> > Department of Nuclear, Plasma & Radiological Engineering (NPRE)
> > University of Illinois at Urbana-Champaign (UIUC)
> > E-mail: huq2090 at gmail.com
> 
> 
> 
> -- 
> 
> Fazlul Huq
> Graduate Research Assistant
> Department of Nuclear, Plasma & Radiological Engineering (NPRE)
> University of Illinois at Urbana-Champaign (UIUC)
> E-mail: huq2090 at gmail.com