<html><body><div style="color:#000; background-color:#fff; font-family:times new roman, new york, times, serif;font-size:12pt"><div>[petsc-users] SLEPc generalized eigenvalue problem question?</div><div><br></div><div>I create 2 matrices using:<br><br>MatCreateSeqDense(PETSC_COMM_SELF, n, n, Ka, &A);<br>MatCreateSeqDense(PETSC_COMM_SELF, n, n, Kb, &B);<br><br>These matrices are 99% zeros ( 16,016,004 entries and 18660 non-zeros).<br> They are symmetric and real. Their tri-diagonal elements are non-zero plus<br>a few other entries.<br><br>I tried to use ex7 for the generalized eigenvalue problem:<br><br>./ex7.exe -f1 k.dat -f2 m.dat -eps_gen_hermitian -eps_smallest_real > x.out<br>2>&1<br><br>without specifying an EPS and get:<br><br>Generalized eigenproblem stored in file.<br><br>Reading REAL matrices from binary files...<br>Number of iterations of the method: 500<br>Number of linear iterations of the method: 4009<br>Solution method:
krylovschur<br><br>Number of requested eigenvalues: 1<br>Stopping condition: tol=1e-07, maxit=500<br>Number of converged approximate eigenpairs: 0<br><br>Is krylovschur inappropriate for this problem or have I set up the problem<br>incorrectly by using MatCreateSeqDense(...) to create the matrix input<br>files in PETSc binary form?</div><div><br></div><div>
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