Cheby can be tricky, textbook algorithms (eg, Saad's book) have some curve balls. Prometheus has a Cheby implementation that I know is correct. It was worked on by several good people and implemented in several codes and we wrote a paper on it.
Mark On May 23, 2012, at 9:21 AM, Barry Smith wrote: > > On May 22, 2012, at 4:17 PM, Hong Zhang wrote: > >> Barry, >> Do you recall the paper or detailed Chebyshev algorithm that you implemented >> the Chebyshev in petsc? > > No > >> I added 'hybrid' to it, which is not correct. Jie is helping to fix it. >> Having an original >> algorithm would help. > > The code has also heavily evolved since first being code with bells and > whistles being added. > > Perhaps look at the templates book for the definitive algorithm :-) > > > > Barry > >> >> On Tue, May 22, 2012 at 1:21 PM, Jie Chen <jiechen at mcs.anl.gov> wrote: >> Then do you know who wrote the code? Hong said it was you. >> >> It was written in the 90s, before version control history. >> Sorry, my mistake. I recall that Barry said that he wrote it when Jed was in >> dia... ;-( >> Hong >> >> >> Hong is trying to modify the code but there is something wrong. I am helping >> to see what is the problem. The code itself is fine. >> >> Hard to speculate without more than "something wrong". >> >> >> Jie >> >> >> >> ----- Original Message ----- >> From: "Jed Brown" <jedbrown at mcs.anl.gov> >> To: "Jie Chen" <jiechen at mcs.anl.gov>, "For users of the development >> version of PETSc" <petsc-dev at mcs.anl.gov> >> Sent: Tuesday, May 22, 2012 1:18:07 PM >> Subject: Re: cheby.c >> >> >> On Tue, May 22, 2012 at 12:37 PM, Jie Chen < jiechen at mcs.anl.gov > wrote: >> >> >> Jed, I am reading your implementation of the chebyshev code. The algorithm >> does not seem to be the same as the version I am familiar with. Did you >> implement it according to some paper or book? >> >> >> >> I didn't write it. >> >> >> What do you find strange? >> >> > >
