dolfin team mailing list archive

[Catherine Micek <mice0012@xxxxxxx>]

Hi,

I have been looking at demo3.py in the dolfin demos in "sandbox/la/ 
trilinos/", which solves the Stokes system using preconditioners and  
an iterative solver.  I can follow the code until it gets to applying  
the boundary conditions:

# apply bc
for bc in bcs:
    bc.apply(A00, b0, a00)
    bc.zero(A01, a00)

Why do you apply the second command as "bc.zero(A01, a00)?"  I would  
have guessed something more like "bc.zero(A01, a01)."  Perhaps the  
better question is more general: how do the bc.apply and bc.zero  
commands work?

Thanks!
Katy