[petsc-users] Problem Using EPSGetEigenpair

[Jose E. Roman]

You are printing the variable as an integer, and it is not an integer, it's a PetscScalar. Use %g
Jose


> El 8 feb 2019, a las 15:02, Eda Oktay via petsc-users <petsc-users at mcs.anl.gov> escribió:
> 
> Hello,
> 
> I am trying to test EPSGetEigenpair function on ex11 in EPS. 
> 
> First, I executed ex11 and get 0.097887 as eigenvalue (k).
> 
> Then under the code 
> 
> ierr = PetscPrintf(PETSC_COMM_WORLD," Number of requested eigenvalues: %D\n",nev);CHKERRQ(ierr);
> 
> I added the following code:
> 
>   ierr = EPSGetEigenpair(eps,0,&kr,NULL,NULL,NULL);  
>   ierr = PetscPrintf(PETSC_COMM_WORLD," Requested eigenvalue: %D\n",kr);CHKERRQ(ierr);
> 
> After execution, I expected to find 0.097887 but the requested eigenvalue was found as -876957631.
> 
> Why EPSGetEigenpair couldn't give 0.097887, isn't  0.097887 the eigenvalue that EPSSetWhichEigenpairs(eps,EPS_SMALLEST_REAL) calculated?
> 
> Best regards,
> 
> Eda