pc_factor_fill

Waad Subber w_subber at yahoo.com
Thu Nov 22 12:55:38 CST 2007


Thanks Barry

One more question please:

Should I get and set the fill factor  like this:

      call MatGetInfo(A,MAT_LOCAL,info,ierr)
      FACTFILL = info(MAT_INFO_fill_ratio_needed)
      call PCFactorSetFill(pc,FACTFILL,ierr)
      call ISSetPermutation(indexSet,IERR);CHKERRQ(IERR)
      call MatLUFactorSymbolic(A,indexSet,indexSet,FACTFILL,... 
      call MatLUFactorNumeric(A,FACTFILL,factorMat,IERR)

Thanks

Waad

Barry Smith <bsmith at mcs.anl.gov> wrote: 

  PCFactorSetFill() after calling KSPSetPC()

   Barry


  If you are using multiple different KSP's you might look at KSPSetOptionsPrefix()
to allow using command line options to set different values for different solvers.

On Nov 22, 2007, at 5:46 AM, Waad Subber wrote:

Hello PETSc Users,

I have a serial code to solve multiple matrices. I am using LU factorization. When I run the code  with the (-info) option, it gives me different values for (pc_factor_fill) depending on the input matrix. I am wondering if I can set these values for the (pc_factor_fill) inside the code instead of running it with runtime option, for it is one code with multiple inputs.
 
 Thanks a lot
 
 Waad


For Matrix No.1

[5] MatLUFactorSymbolic_SeqAIJ(): Reallocs 3 Fill ratio:given 0 needed 2.96
[5] MatLUFactorSymbolic_SeqAIJ(): Run with -pc_factor_fill 2.96 or use
[5] MatLUFactorSymbolic_SeqAIJ(): PCFactorSetFill(pc,2.96);
[5] MatLUFactorSymbolic_SeqAIJ(): for best performance.

For Matrix No.2

[9] MatLUFactorSymbolic_SeqAIJ(): Reallocs 3 Fill ratio:given 0 needed 2.42069
[9] MatLUFactorSymbolic_SeqAIJ(): Run with -pc_factor_fill 2.42069 or use
[9] MatLUFactorSymbolic_SeqAIJ(): PCFactorSetFill(pc,2.42069);
[9] MatLUFactorSymbolic_SeqAIJ(): for best performance.

For Matrix No. n

[8] MatLUFactorSymbolic_SeqAIJ(): Reallocs 3 Fill ratio:given 0 needed 1.87742
[8] MatLUFactorSymbolic_SeqAIJ(): Run with -pc_factor_fill 1.87742 or use
[8] MatLUFactorSymbolic_SeqAIJ(): PCFactorSetFill(pc,1.87742);
[8] MatLUFactorSymbolic_SeqAIJ(): for best performance.
       


---------------------------------
Be a better sports nut! Let your teams follow you with Yahoo Mobile. Try it now.




       
---------------------------------
Be a better pen pal. Text or chat with friends inside Yahoo! Mail. See how.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20071122/1e9b12b4/attachment.htm>


More information about the petsc-users mailing list