[petsc-users] EPSGetEigenpair Error

[Jose E. Roman]

The index i should be a value between 0 and nconv-1 
https://slepc.upv.es/documentation/current/docs/manualpages/EPS/EPSGetEigenpair.html
Jose

> El 6 jul 2020, a las 11:06, Eda Oktay <eda.oktay at metu.edu.tr> escribió:
> 
> Hello,
> 
> I am using EPSGetEigenpair to find some matrices' eigenpairs:
> 
> ierr = EPSGetType(eps,&type);CHKERRQ(ierr)
>  ierr = EPSGetDimensions(eps,&nev,NULL,NULL);CHKERRQ(ierr);
>  ierr = MatCreateVecs(L,&vr,NULL);CHKERRQ(ierr);
>  Vec *V;
>  VecDuplicateVecs(vr,nev,&V);
>  for (i=0; i<nev;i++){
>  ierr = EPSGetEigenpair(eps,i,&kr,NULL,V[i],NULL);
>  }
> 
> However, for some matrices, even though nev = 2, I am getting the
> following error:
> 
> [0]PETSC ERROR: --------------------- Error Message
> --------------------------------------------------------------
> [0]PETSC ERROR: Argument out of range
> [0]PETSC ERROR: Argument 2 out of range
> [0]PETSC ERROR: See
> https://www.mcs.anl.gov/petsc/documentation/faq.html for trouble
> shooting.
> [0]PETSC ERROR: Petsc Release Version 3.13.2, Jun 02, 2020
> [0]PETSC ERROR: ./deneme_new_vecscatter_arastep on a
> arch-linux2-c-debug named b342.wls.metu.edu.tr by edaoktay Mon Jul  6
> 12:01:14 2020
> [0]PETSC ERROR: Configure options --with-cc=gcc --with-cxx=g++
> --download-mpich --download-openblas --download-slepc --download-metis
> --download-parmetis --download-chaco --with-X=1
> [0]PETSC ERROR: #1 EPSGetEigenpair() line 411 in
> /home/edaoktay/petsc-3.13.2/arch-linux2-c-debug/externalpackages/git.slepc/src/eps/interface/epssolve.c
> 
> ===================================================================================
> =   BAD TERMINATION OF ONE OF YOUR APPLICATION PROCESSES
> =   PID 8635 RUNNING AT b342.wls.metu.edu.tr
> =   EXIT CODE: 134
> =   CLEANING UP REMAINING PROCESSES
> =   YOU CAN IGNORE THE BELOW CLEANUP MESSAGES
> ===================================================================================
> YOUR APPLICATION TERMINATED WITH THE EXIT STRING: Aborted (signal 6)
> This typically refers to a problem with your application.
> Please see the FAQ page for debugging suggestions
> 
> What can be the reason? I am getting this message when i = 0, so how
> can 0 be out of range for nev = 2?
> 
> And why am I getting this message for 2 matrices out of 16?
> 
> Thanks!