[petsc-users] How to set L1 norm as the converge test?

[Barry Smith]

  Brian,

   Do you wish to monitor the convergence of the L1 norm, or do you wish to use the L1 norm in the convergence test?   Regardless you cannot change the LSQR or CG to be a different algorithm (with different convergence properties) with the L1 norm.


  Barry

On Sep 24, 2014, at 2:08 PM, Brian Yang <brianyang1106 at gmail.com> wrote:

> Hi all,
> 
> For example, I am using LSQR or CG to solve Ax=b.
> 
> When we turn on the monitor option of solving the linear system, we could see iteration number and residual for each iteration. I believe it's L2 norm of the objective function?
> 
> If yes, is there a way that I could set it to L1 norm for solving the system?
> 
> Thanks.
> 
> -- 
> Brian Yang
> U of Houston
> 
> 
>