[petsc-users] Convert MatNest to MatAIJ

[Thomas Witkowski]

Is there a fast way to convert a MatNest to a MatAIJ? I tried to use 
MatConvert, but it seems that this convert is not yet implemented. As I 
need this functionality to factorize the nested matrix with MUMPS, is 
there any better way than to extract the nested matrices, iterate over 
all rows of these matrices and use MatSetValues to add them again to the 
final MatAIJ?

Thomas