dolfin team mailing list archive

[mspieg <mspieg@xxxxxxxxxxxxxxxxx>]

Hi all,
   A slightly strange query...

I've been writing hybrid dolfin/Petsc codes (forgive me) that allow  
dolfin assembly routines to be used with PETSc native Non-linear  
solvers (SNES) which currentlyprovide a richer set of pre- 
conditioners and line-search algorithms than Dolfin's newton_solver.
Anyway, in 0.8.1, it was possible (and very useful) to construct  
PETScVectors directly from a raw PETSc Vec that may be passed, for  
example,  to a user-supplied function that might look something like

	PetscErrorCode FormFunction(Vec x, Vec f, ....)
	{
		PETScVector X(x), F(f);
		...
		u.vector()=X; //assuming u is attached to form L
		assemble(F,L);
		...
	}
etc...

Is there any way to do this now in  0.9.x where the PETScVector  
constructor now requires a boost::shared_ptr<Vec>?  I believe, I can  
work around this with VecCopy, but it would be much nicer just to be  
able to wrap the pointer.  Apologies if this is an obvious  
question...I'm still trying to get my head around shared_ptr  and it  
is not clear to me that you can construct one directly from a raw  
pointer.

as always, Any help greatly appreciated
marc


----------------------------------------------------
Marc Spiegelman
Lamont-Doherty Earth Observatory
Dept. of Applied Physics/Applied Math
Columbia University
http://www.ldeo.columbia.edu/~mspieg
tel: 845 704 2323 (SkypeIn)
----------------------------------------------------