[petsc-dev] How do you get RIchardson?

[Matthew Knepley]

On Fri, Sep 16, 2011 at 4:38 PM, Jed Brown <jedbrown at mcs.anl.gov> wrote:

> On Fri, Sep 16, 2011 at 23:21, Matthew Knepley <knepley at gmail.com> wrote:
>
>> it still converges, conditionally to the same solution as exact
>>> newton. Variations for A yield different rates of convergence. When
>>> A=1, you get the classical Picard iteration that Matt mentioned (?).
>>>
>>
>> Not even close.
>>
>
> From Barry's description at the top of this thread:
>
>  x^{n+1}   = x^{n}  - lambda F(x^{n})
>
>
> This looks oddly similar to
>
>  x^{n+1}   = x^{n}  - J(x^n)^{-1} F(x^{n})
>
> I wonder where I've seen that before.
>

So you are saying that you agree with me, what is coded is in fact the
Picard iteration, and we are done arguing?

   Matt

-- 
What most experimenters take for granted before they begin their experiments
is infinitely more interesting than any results to which their experiments
lead.
-- Norbert Wiener
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