On Sat, Nov 30, 2019 at 3:19 PM baikadi pranay <[email protected]> wrote:
> Hello PETSc users, > > I am currently trying to build a 1-D Schrodinger solver. I have built my > hamiltonian matrix (of size 121 x 121) and i'm trying to find the > eigenvalues. I have the following lines of code for the solver: > > *call EPSCreate(PETSC_COMM_WORLD,eps,ierr)* > > *call EPSSetOperators(eps,ham,S,ierr)call > EPSSetProblemType(eps,EPS_GHEP,ierr)* > > > > *call EPSSetFromOptions(eps,ierr)call > EPSSetDimensions(eps,10,PETSC_DEFAULT_INTEGER,PETSC_DEFAULT_INTEGER,ierr)call > EPSSolve(eps,ierr)call EPSDestroy(eps,ierr)* > > At the EPSSolve line, i get the following error: > > > > > > *[0]PETSC ERROR: --------------------- Error Message > --------------------------------------------------------------[0]PETSC > ERROR: Floating point exception[0]PETSC ERROR: Vec entry at local location > 0 is not-a-number or infinite at end of function: Parameter number > 3[0]PETSC ERROR: See http://www.mcs.anl.gov/petsc/documentation/faq.html > <http://www.mcs.anl.gov/petsc/documentation/faq.html> for trouble > shooting.[0]PETSC ERROR: Petsc Release Version 3.11.1, Apr, 12, 2019* > You need to show the entire stack trace that is output here. Thanks, Matt > I am using the options *-st_pc_factor_shift_type NONZERO > -st_pc_factor_shift_amount 1* ( else I end up getting the "zero pivot > in LU factorization" error ). > > I outputted my matrix to matlab and confirmed that the null space is empty > and the matrix is not singular. I am not sure why I'm getting this error. > Could you provide me a hint as to how to solve this problem. > > Sincerely, > Pranay. > -- What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead. -- Norbert Wiener https://www.cse.buffalo.edu/~knepley/ <http://www.cse.buffalo.edu/~knepley/>
