On 12/3/06, Ben Tay <zonexo at gmail.com> wrote: > Hi, > > I'm still relatively new to PETSC but I've finally managed to solve my own > poisson eqn using it in about a week's time.Thank you for writing such a > good solver. > > However, I have some questions still about PETSC: > > 1. Are petscscaler the same as real nos.? I am writing in double precision > or real(8). So are these 2 interchangeable? (same as petscint and integer).
Yes. > 2. while linking in compaq visual fortran, I get the warning message about > conflict library with LIBCMT. Is it important or can I just ignore it? This is determined by your configure. Satish will know better how to control it. > 3. I am writing in f90 free form format. When I modify from fixed f77 format > to f90, it gives me a lot of error, which seems to be the include file > error. So, is it possible to write in f90 format? Depending on which compiler you use, you might have to give a flag. For g95 it is -ffree-form. > 4. I am writing a Navier stokes solver and I'm using PETSC to solve the > poisson eqn. If only the RHS changes with each time step, do I need to call > > VecCreateSeq > <insert values in RHS b> > VecAssemblyBegin > VecAssemblyEnd > VecDestroy > > at each time step? I don't think I can (or I should) change values of b > after VecAssemblyBegin,VecAssemblyEnd, or can I? You can just change the values. Call AssemblyBegin/End() after each group of changes. Matt > > Thank you very much and have a nice day > > Regards, > Ben -- "Failure has a thousand explanations. Success doesn't need one" -- Sir Alec Guiness
