<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div class="">Hi Jose, </div><div class=""><br class=""></div><div class=""> I also read these matrices into matlab and found the eigenvalues as</div><div class=""><br class=""></div><div class=""><div class="">>>A = PetscBinaryRead('A.petsc’);</div><div class="">>>B = PetscBinaryRead(‘B.petsc’);</div><div class="">>> [v,d] = eigs(A,B)</div><div class="">(*** got a lot of output about poor-conditioning ***)</div><div class="">>> diag(d)</div><div class=""><br class=""></div><div class="">ans =</div><div class=""><br class=""></div><div class=""> 1.0e-05 *</div><div class=""><br class=""></div><div class=""> -0.2219</div><div class=""> 0.0229</div><div class=""> 0.0229</div><div class=""> 0.0025</div><div class=""> 0.0019</div><div class=""> 0.0014</div><div class=""><br class=""></div><div class="">>> So, one of these is turning out to be negative, but I am still getting numbers. </div></div><div class=""><br class=""></div><div class=""><br class=""></div><div class=""><br class=""></div><div class="">Using these matrices with ex7 produces an error:</div><div class=""><br class=""></div><div class=""><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(245, 245, 245); background-color: rgb(0, 0, 0);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">Dhcp-90-243:T_400_V_0 manav$ /Users/manav/Documents/codes/numerical_lib/slepc/slepc-3.6.2/src/eps/examples/tutorials/ex7 -f1 A.petsc -f2 B.petsc -eps_gen_hermitian -eps_view -eps_nev 1 </span></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(245, 245, 245); background-color: rgb(0, 0, 0); min-height: 14px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""></span><br class=""></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(245, 245, 245); background-color: rgb(0, 0, 0);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">Generalized eigenproblem stored in file.</span></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(245, 245, 245); background-color: rgb(0, 0, 0); min-height: 14px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""></span><br class=""></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(245, 245, 245); background-color: rgb(0, 0, 0);" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> Reading REAL matrices from binary files...</span></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(195, 55, 32); background-color: rgb(0, 0, 0);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">[0]PETSC ERROR: --------------------- Error Message --------------------------------------------------------------</span></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(245, 245, 245); background-color: rgb(0, 0, 0);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">[0]PETSC ERROR: Error in external library</span></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(245, 245, 245); background-color: rgb(0, 0, 0);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">[0]PETSC ERROR: Error in Lapack xSTEQR 15</span></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(245, 245, 245); background-color: rgb(0, 0, 0);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">[0]PETSC ERROR: See <a href="http://www.mcs.anl.gov/petsc/documentation/faq.html" class="">http://www.mcs.anl.gov/petsc/documentation/faq.html</a> for trouble shooting.</span></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(245, 245, 245); background-color: rgb(0, 0, 0);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">[0]PETSC ERROR: Petsc Release Version 3.6.3, Dec, 03, 2015 </span></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(245, 245, 245); background-color: rgb(0, 0, 0);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">[0]PETSC ERROR: /Users/manav/Documents/codes/numerical_lib/slepc/slepc-3.6.2/src/eps/examples/tutorials/ex7 on a arch-darwin-cxx-opt named <a href="http://ws243-49.walker.dynamic.msstate.edu" class="">ws243-49.walker.dynamic.msstate.edu</a> by manav Mon Apr 4 11:05:30 2016</span></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(245, 245, 245); background-color: rgb(0, 0, 0);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">[0]PETSC ERROR: Configure options --prefix=/Users/manav/Documents/codes/numerical_lib/petsc/petsc-3.6.3/../ --CC=mpicc --CXX=mpicxx --FC=mpif90 --with-clanguage=c++ --with-fortran=0 --with-mpiexec=/opt/local/bin/mpiexec --with-shared-libraries=1 --with-x=1 --with-x-dir=/opt/X11 --with-debugging=0 --with-lapack-lib=/usr/lib/liblapack.dylib --with-blas-lib=/usr/lib/libblas.dylib --download-superlu=yes --download-superlu_dist=yes --download-suitesparse=yes --download-mumps=yes --download-scalapack=yes --download-parmetis=yes --download-parmetis-shared=1 --download-metis=yes --download-metis-shared=1 --download-hypre=yes --download-hypre-shared=1 --download-ml=yes --download-ml-shared=1 --download-sundials=yes --download-sundials-shared=1</span></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(245, 245, 245); background-color: rgb(0, 0, 0);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">[0]PETSC ERROR: #1 DSSolve_HEP_QR() line 495 in /Users/manav/Documents/codes/numerical_lib/slepc/slepc-3.6.2/src/sys/classes/ds/impls/hep/dshep.c</span></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(245, 245, 245); background-color: rgb(0, 0, 0);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">[0]PETSC ERROR: #2 DSSolve() line 543 in /Users/manav/Documents/codes/numerical_lib/slepc/slepc-3.6.2/src/sys/classes/ds/interface/dsops.c</span></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(245, 245, 245); background-color: rgb(0, 0, 0);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">[0]PETSC ERROR: #3 EPSSolve_KrylovSchur_Symm() line 68 in /Users/manav/Documents/codes/numerical_lib/slepc/slepc-3.6.2/src/eps/impls/krylov/krylovschur/ks-symm.c</span></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(245, 245, 245); background-color: rgb(0, 0, 0);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">[0]PETSC ERROR: #4 EPSSolve() line 101 in /Users/manav/Documents/codes/numerical_lib/slepc/slepc-3.6.2/src/eps/interface/epssolve.c</span></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(245, 245, 245); background-color: rgb(0, 0, 0);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">[0]PETSC ERROR: #5 main() line 147 in /Users/manav/Documents/codes/numerical_lib/slepc/slepc-3.6.2/src/eps/examples/tutorials/ex7.c</span></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(245, 245, 245); background-color: rgb(0, 0, 0);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">[0]PETSC ERROR: PETSc Option Table entries:</span></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(245, 245, 245); background-color: rgb(0, 0, 0);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">[0]PETSC ERROR: -eps_gen_hermitian</span></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(245, 245, 245); background-color: rgb(0, 0, 0);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">[0]PETSC ERROR: -eps_nev 1</span></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(245, 245, 245); background-color: rgb(0, 0, 0);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">[0]PETSC ERROR: -eps_view</span></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(245, 245, 245); background-color: rgb(0, 0, 0);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">[0]PETSC ERROR: -f1 A.petsc</span></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(245, 245, 245); background-color: rgb(0, 0, 0);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">[0]PETSC ERROR: -f2 B.petsc</span></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(245, 245, 245); background-color: rgb(0, 0, 0);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">[0]PETSC ERROR: -matload_block_size 1</span></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(195, 55, 32); background-color: rgb(0, 0, 0);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">[0]PETSC ERROR: ----------------End of Error Message -------send entire error message to <a href="mailto:petsc-maint@mcs.anl.gov" class="">petsc-maint@mcs.anl.gov</a>----------</span></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(245, 245, 245); background-color: rgb(0, 0, 0);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">--------------------------------------------------------------------------</span></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(245, 245, 245); background-color: rgb(0, 0, 0);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">MPI_ABORT was invoked on rank 0 in communicator MPI_COMM_WORLD </span></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(245, 245, 245); background-color: rgb(0, 0, 0);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">with errorcode 76.</span></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(245, 245, 245); background-color: rgb(0, 0, 0); min-height: 14px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""></span><br class=""></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(245, 245, 245); background-color: rgb(0, 0, 0);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">NOTE: invoking MPI_ABORT causes Open MPI to kill all MPI processes.</span></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(245, 245, 245); background-color: rgb(0, 0, 0);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">You may or may not see output from other processes, depending on</span></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(245, 245, 245); background-color: rgb(0, 0, 0);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">exactly when Open MPI kills them.</span></div><div style="margin: 0px; font-size: 10px; line-height: normal; font-family: Monaco; color: rgb(245, 245, 245); background-color: rgb(0, 0, 0);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">--------------------------------------------------------------------------</span></div></div><div class=""><br class=""></div><div class=""><br class=""></div><div class=""><br class=""></div><br class=""><div><blockquote type="cite" class=""><div class="">On Apr 4, 2016, at 10:49 AM, Manav Bhatia <<a href="mailto:bhatiamanav@gmail.com" class="">bhatiamanav@gmail.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div class="">I just sent you the updated matrices on slepc-main. <br class=""><br class="">Sorry about sending the wrong matrices earlier. <br class=""><br class="">Regards,<br class="">Manav<br class=""><br class=""><br class=""><blockquote type="cite" class="">On Apr 4, 2016, at 9:42 AM, Manav Bhatia <<a href="mailto:bhatiamanav@gmail.com" class="">bhatiamanav@gmail.com</a>> wrote:<br class=""><br class="">Ok. So, I ran ex7 with the same command-line options in your email, and got a result. This is on my Mac OS X, without any changes to the lapack/blas/slepc library. <br class=""><br class="">I also ran my code on a linux machine with lapack/blas build from source (obtained from netlib), and got the same error as on my mac.<br class=""><br class="">Not sure how to go about debugging this. <br class=""><br class="">-Manav<br class=""><br class=""><br class=""><blockquote type="cite" class="">On Apr 4, 2016, at 3:46 AM, Jose E. Roman <<a href="mailto:jroman@dsic.upv.es" class="">jroman@dsic.upv.es</a>> wrote:<br class=""><br class=""><br class=""><blockquote type="cite" class="">El 3 abr 2016, a las 22:17, Manav Bhatia <<a href="mailto:bhatiamanav@gmail.com" class="">bhatiamanav@gmail.com</a>> escribió:<br class=""><br class="">I just send you the matrices. <br class=""><br class="">Thanks,<br class="">Manav<br class=""></blockquote><br class="">I cannot reproduce the problem. I was able to compute the eigenvalues without problems with Krylov-Schur (note that I scaled matrix A by 1e7 because the eigenvalues are tiny):<br class=""><br class="">$ ./ex7 -f1 A.petsc -f2 B.petsc -eps_gen_hermitian<br class=""><br class="">Generalized eigenproblem stored in file.<br class=""><br class="">Reading REAL matrices from binary files...<br class="">Number of iterations of the method: 1<br class="">Number of linear iterations of the method: 17<br class="">Solution method: krylovschur<br class=""><br class="">Number of requested eigenvalues: 1<br class="">Stopping condition: tol=1e-08, maxit=768<br class="">Linear eigensolve converged (6 eigenpairs) due to CONVERGED_TOL; iterations 1<br class="">---------------------- --------------------<br class=""> k ||Ax-kBx||/||kx||<br class="">---------------------- --------------------<br class=""> 11.410228 3.18851e-09<br class=""> 1.323631 2.33005e-09<br class=""> 1.323631 3.98884e-09<br class=""> 0.224497 1.24334e-08<br class=""> 0.168344 9.81685e-08<br class=""> 0.129229 4.85372e-08<br class="">---------------------- --------------------<br class=""><br class="">Note that I am solving the problem as a GHEP, and this gives far better residuals than solving as a GNHEP. The Arnoldi solver did not fail either.<br class=""><br class="">I don't know what caused your error. You can try configuring with the source Lapack: --download-f2cblaslapack<br class=""><br class="">Jose<br class=""><br class=""></blockquote><br class=""></blockquote><br class=""></div></div></blockquote></div><br class=""></body></html>