<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">Hello,<div class="">Has there been any follow-up on this <a href="https://lists.mcs.anl.gov/pipermail/petsc-users/2015-January/024020.html" class="">https://lists.mcs.anl.gov/pipermail/petsc-users/2015-January/024020.html</a>?<br class=""><div class="">Given a 3x3 MatNest A = [A_00,0,0 ; 0,A_11,0 ; 0,0,A_22], I’d like to setup a two-way fieldsplit coupling [A_00,0 ; 0,A_11] and [A_22] but I can’t figure out the proper options.</div></div><div class="">Jed, in this answer <a href="https://lists.mcs.anl.gov/pipermail/petsc-users/2015-January/023993.html" class="">https://lists.mcs.anl.gov/pipermail/petsc-users/2015-January/023993.html</a>, you recommend not to use MatNest. What would you recommend instead?</div><div class="">Even defining a 2x2 MatNest B = [B_00,0 ; 0,A_22] with B_00 = [A_00,0 ; 0,A_11] sounds bad to you?</div><div class=""><br class=""></div><div class="">Thanks for your help,</div><div class="">Pierre</div><div class=""><br class=""></div><div class="">PS: this is just a dummy example with 0s everywhere.</div><div class=""><br class=""></div><div class=""></div></body></html>