<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,<div class=""><br class=""></div><div class="">I have a question about, I want to use AMG as a solver in PETSc, but from the user manual, I find that AMG only can be used as a preconditioner. Am I right?</div><div class=""><br class=""></div><div style="orphans: 2; widows: 2;" class="">So I want to use the boomerAMG in HYPRE as the solver, Can I use the function like <strong style="orphans: 2; widows: 2;" class=""><font class=""><font color="#000000" class="">VecHYPRE_IJVectorCreate (Petsc <span style="caret-color: rgb(0, 0, 0);" class="">function</span>) </font></font><font class="">in these links? </font></strong></div><div class=""><strong style="orphans: 2; widows: 2;" class=""><font class=""><br class=""></font></strong></div><div class=""><strong style="orphans: 2; widows: 2;" class=""><a href="https://petsc.org/release/src/vec/vec/impls/hypre/vhyp.c" class="">https://petsc.org/release/src/vec/vec/impls/hypre/vhyp.c</a>. (</strong><strong style="orphans: 2; widows: 2;" class="">It Creates hypre ijvector from Petsc vector)</strong></div><div class=""><strong style="orphans: 2; widows: 2;" class=""><a href="https://petsc.org/main/src/mat/impls/hypre/mhypre.c.html" class="">https://petsc.org/main/src/mat/impls/hypre/mhypre.c.html</a> </strong><strong style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0); orphans: 2; widows: 2;" class=""> (</strong><strong style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0); orphans: 2; widows: 2;" class="">It Creates hypre ijmatrix from Petsc matrix)</strong></div><div class=""><strong style="orphans: 2; widows: 2;" class=""><br class=""></strong></div><div class=""><strong style="orphans: 2; widows: 2;" class=""><br class=""></strong></div><div class=""><strong style="orphans: 2; widows: 2;" class="">But there is a another </strong><b class="">question: how to transfer the vector/matrix structure from hypre back petsc ?</b></div><div class=""><b class=""><br class=""></b></div><div class=""><b class="">I don’t find any function for that work, Do you know what function can work, or </b><b class="">do I implement this function by myself?</b></div><div class=""><b class=""><br class=""></b></div><div class=""><b class=""><br class=""></b></div><div class=""><b class=""><br class=""></b></div><div class="">Thanks,</div><div class="">Sijie</div><div class=""><br class=""></div></body></html>