<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="">Hi, all<div class=""><br class=""></div><div class="">I am trying to apply LDG to discretizing 1D diffusion term u_{xx} with Dirichlet boundary condition. The difficulty I have is that I want to zero all entries (except the diagonal one needs to be set as 1.0) of the beginning and ending DOF rows of the sparse matrix.</div><div class=""><br class=""></div><div class="">I have tried the MatZeroRows and MatZeroRowsStencil. However, I can only change the very first and last row of the matrix with them. This isn’t right when DOF > 1 because I need to zero the first DOF rows (the diagonal should be set as identity).</div><div class=""><br class=""></div><div class="">I was wondering if there is anyway I can take to zero the first and last DOF rows (with identity matrix diagonal) in a block-wise style.</div><div class=""><br class=""></div><div class="">Let me know if any further explanation is needed.</div><div class=""><br class=""></div><div class="">Thank you in advance!</div><div class=""><br class=""><div class="">
<div dir="auto" style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><div style="color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px;">Mingchang Ding</div><div style="color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px;">Graduate Student<br class="">EWG 111<br class="">Department of Mathematical Sciences<br class="">University of Delaware</div><div style="color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><br class=""></div><br class="Apple-interchange-newline"></div><br class="Apple-interchange-newline">
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