Tim Kroeger tim.kroeger at
Mon Jan 19 04:18:20 CST 2009

Dear Matt,

On Fri, 16 Jan 2009, Matthew Knepley wrote:

> On Fri, Jan 16, 2009 at 6:58 AM, Tim Kroeger <
> tim.kroeger at> wrote:
>> If I create a vector using VecCreateGhost() and then query the local size
>> using VerGetLocalSize(), will the resulting number then include the number
>> of ghost values or not?  In either case, how can I ask a vector about the
>> number of ghost values that are stored locally?
> No, it will have the local size without ghosts. You can get the number of
> ghosts from the size of the local form VecGhostGetLocalForm()
> or from the size of the LocalToGlobalMapping.

Thank you very much.  My next question: How do I obtain the vector's 
LocalToGlobalMapping?  I thought there would be a function like 
VecGhostGetLocalToGlobalMapping(), but that doesn't exist.  Can you 
help me?

Best Regards,


Dr. Tim Kroeger
tim.kroeger at            Phone +49-421-218-7710
tim.kroeger at            Fax   +49-421-218-4236

Fraunhofer MEVIS, Institute for Medical Image Computing
Universitaetsallee 29, 28359 Bremen, Germany

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