1445     IS              isx, isv, istmp;  in SetProblem()  local
1460     PetscCall(ISCreateBlock(PETSC_COMM_WORLD, dim, Np, idx, PETSC_COPY_VALUES, &isv));  in SetProblem()
1464     PetscCall(TSRHSSplitSetIS(ts, "momentum", isv));  in SetProblem()
1466     PetscCall(ISDestroy(&isv));  in SetProblem()
1543   IS       isx, isv;  in InitializeSolveAndSwarm()  local
1559   PetscCall(TSRHSSplitGetIS(ts, "momentum", &isv));  in InitializeSolveAndSwarm()
1563   PetscCall(VecISCopy(u, isv, SCATTER_FORWARD, gv));  in InitializeSolveAndSwarm()
1589     IS         isx, isv;  in MigrateParticles()  local
1594     PetscCall(TSRHSSplitGetIS(ts, "momentum", &isv));  in MigrateParticles()
1596     PetscCall(VecGetSubVector(u, isv, &momentum));  in MigrateParticles()
1602     PetscCall(VecISCopy(u, isv, SCATTER_REVERSE, gv));  in MigrateParticles()
1634     PetscCall(VecRestoreSubVector(u, isv, &momentum));  in MigrateParticles()