[petsc-users] How to use multigrid?

[w_ang_temp]

Hello,Jed
   
    Sorry again for the interruption.
   
    As you said, if I want to use Algebraic multigrid, I can just use '-pc_type gamg
-pc_gamg_agg_nsmooths 1' in the command line. I think there are many other -pc_gamg_XXX
parameters. How can I find all the -pc_gamg_XXX?
   
    Besides, I want to know more about AMG. Are there any details from PETSc, like manual,
documentaion, FAQ, etc?
    Also, from the above post, I want to know that if AMG can not be used in 3.2 by command
line option, because now I have to use 3.3 for using AMG. I just donot want to change my
version 3.2 now.
   
    I am major in Civil Engineering and not good at math and programming. So please
forgive my weakness.
    Thanks.
                                Jim
 







>At 2012-10-28 21:17:00,"Jed Brown" <jedbrown at mcs.anl.gov> wrote:


>Algebraic multigrid can be used directly, -pc_type gamg -pc_gamg_agg_nsmooths 1. Geometric either required that you use the PCMG interface to set >interpolation (and provide a coarse operator for non-Galerkin) or use a DM that provides coarsening capability.

>What kind of problem are you solving?

>>On Oct 28, 2012 6:09 AM, "w_ang_temp" <w_ang_temp at 163.com> wrote:

>>Hello,
 >>  I want to use the multigrid as a preconditioner. The introduction about it in the manual is little.
>>So are there some typical examples or details about multigrid? Is it used just like other preconditioners
>>like jacobi, sor, which can be simply used in the cammand line options?
 >>  Thanks.
 > >                                                                     Jim


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20121109/1a8a6eea/attachment.html>