[petsc-dev] this is a bit annoying

[Jed Brown]

This is the old crappy approach of using VecScatter to move indices.
I'm sure it still exists in several places, but should be replaced with
SF.

"Smith, Barry F." <bsmith at mcs.anl.gov> writes:

> [0]PETSC ERROR: --------------------- Error Message --------------------------------------------------------------
> #	[0]PETSC ERROR: No support for this operation for this object type
> #	[0]PETSC ERROR: No support when scalars smaller than integers
> #	[0]PETSC ERROR: See http://www.mcs.anl.gov/petsc/documentation/faq.html for trouble shooting.
> #	[0]PETSC ERROR: Petsc Development GIT revision: v3.8.3-951-g28c0c90a4c  GIT Date: 2017-12-31 13:59:15 -0600
> #	[0]PETSC ERROR: ../ex28 on a arch-single-64bitindices named Barrys-MacBook-Pro.local by barrysmith Sun Dec 31 17:13:52 2017
> #	[0]PETSC ERROR: Configure options --with-precision=single --with-64-bit-indices
> #	[0]PETSC ERROR: #1 MatNestCreateAggregateL2G_Private() line 1160 in /Users/barrysmith/Src/petsc/src/mat/impls/nest/matnest.c
> #	[0]PETSC ERROR: #2 MatSetUp_NestIS_Private() line 1342 in /Users/barrysmith/Src/petsc/src/mat/impls/nest/matnest.c
> #	[0]PETSC ERROR: #3 MatNestSetSubMats_Nest() line 1073 in /Users/barrysmith/Src/petsc/src/mat/impls/nest/matnest.c
> #	[0]PETSC ERROR: #4 MatNestSetSubMats() line 1130 in /Users/barrysmith/Src/petsc/src/mat/impls/nest/matnest.c
> #	[0]PETSC ERROR: #5 MatCreateNest() line 1407 in /Users/barrysmith/Src/petsc/src/mat/impls/nest/matnest.c
> #	[0]PETSC ERROR: #6 DMCreateMatrix_Composite_Nest() line 32 in /Users/barrysmith/Src/petsc/src/dm/impls/composite/packm.c
> #	[0]PETSC ERROR: #7 DMCreateMatrix_Composite() line 186 in /Users/barrysmith/Src/petsc/src/dm/impls/composite/packm.c
> #	[0]PETSC ERROR: #8 DMCreateMatrix() line 1178 in /Users/barrysmith/Src/petsc/src/dm/interface/dm.c
> #	[0]PETSC ERROR: #9 main() line 413 in /Users/barrysmith/