changing default values in options database

Boyce Griffith griffith at
Fri Nov 7 12:41:09 CST 2008

Yes, you're right --- I was being stupid and was setting things in the 
wrong order.

A related question: Is there any way to change the list of PC's 
associated with a solver as listed by -help?  For my solver, it only 
makes sense for -pc_type to be "shell" or "none".


-- Boyce

Lisandro Dalcin wrote:
> On Fri, Nov 7, 2008 at 3:12 PM, Matthew Knepley <knepley at> wrote:
>> I think you can just set those values before you call SetFromOptions()
>> and they will show up. However, I have not tried it.
> Yep, that's the way options work in most cases.
>> On Fri, Nov 7, 2008 at 1:06 PM, Boyce Griffith <griffith at> wrote:
>>> Hi, Folks --
>>> Is there a simple way to change these default values for individual solvers?
>>>  In particular, I would like to be able to ensure that the default values
>>> listed by `-help' correspond to the values that I'm specifying in the code.
> As Matt, suggested, use this
> KSPSetTolerances(ksp, ....)
> KSPSetFromOptions(ksp)

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