[petsc-users] DM vector restriction questions

[Barry Smith]

  And VecStrideNorm(), VecStrideScale(), VecStrideNormAll() etc. Let us know what is missing and what you need?

  Barry

On May 25, 2014, at 7:40 PM, Jed Brown <jed at jedbrown.org> wrote:

> Xiangdong <epscodes at gmail.com> writes:
> 
>> Hello everyone,
>> 
>> I have a questions about vectors in an DMDA with DOF>1. For example, in 1d
>> with number of grid N and DOF=2 (two fields u and v), the length of the
>> global vector is 2*N.
>> 
>> What is the best way to restrict this vector (length 2*N) to a vector
>> (length N) corresponding to the field u only?  This will help me obtain the
>> properties of field u by using VecSum and other vec functions.
> 
> http://www.mcs.anl.gov/petsc/petsc-current/docs/manualpages/Vec/VecStrideGather.html