<html><head><meta http-equiv="Content-Type" content="text/html; charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><div class=""><br class=""></div><div class=""> Nathan,</div><div class=""><br class=""></div> Yes, you can call PetscInitializeFortran() from your Fortran library.<div class=""><br class=""></div><div class=""> Barry</div><div class=""><br class=""><div><br class=""><blockquote type="cite" class=""><div class="">On Sep 27, 2021, at 11:59 AM, WUKIE, NATHAN A DR-02 USAF AFMC AFRL/RQVC via petsc-users <<a href="mailto:petsc-users@mcs.anl.gov" class="">petsc-users@mcs.anl.gov</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><meta charset="UTF-8" class=""><div style="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; text-decoration: none; font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;" class="">How should petsc initialization be handled for a python application utilizing petsc4py and a Fortran library application also using petsc?</div><div style="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; text-decoration: none; font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;" class=""><br class=""></div><div style="font-family: Helvetica; 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; text-decoration: none; font-size: 12pt;" class=""><font face="Calibri, Arial, Helvetica, sans-serif" class="">The petsc documentation states that PetscInitializeFortran "</font><span style="font-family: Times; font-weight: 400; font-size: 18px; orphans: 2; widows: 2; background-color: rgb(255, 255, 255); display: inline !important;" class="">should be called soon AFTER the call to<span class=""> </span></span><a href="https://petsc.org/release/docs/manualpages/Sys/PetscInitialize.html#PetscInitialize" style="font-family: Times; font-weight: 400; font-size: 18px; orphans: 2; widows: 2;" class="">PetscInitialize</a><span style="font-family: Times; font-weight: 400; font-size: 18px; orphans: 2; widows: 2; background-color: rgb(255, 255, 255); display: inline !important;" class="">() if one is using a C main program that calls Fortran routines that in turn call PETSc routines"</span><span style="font-weight: 400; font-size: 18px; orphans: 2; widows: 2; background-color: rgb(255, 255, 255); display: inline !important;" class=""><font face="Calibri, Arial, Helvetica, sans-serif" class="">. Does petsc4py.init(...) call PetscInitializeFortran? Is it permissible to call PetscInitializeFortran from the fortran library application itself? Or must PetscInitializeFortran be called from the C main program?</font></span></div><div style="font-family: Helvetica; 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; text-decoration: none; font-size: 12pt;" class=""><span style="font-weight: 400; font-size: 18px; orphans: 2; widows: 2; background-color: rgb(255, 255, 255); display: inline !important;" class=""><font face="Calibri, Arial, Helvetica, sans-serif" class=""><br class=""></font></span></div><div style="font-family: Helvetica; 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; text-decoration: none; font-size: 12pt;" class=""><span style="font-weight: 400; font-size: 18px; orphans: 2; widows: 2; background-color: rgb(255, 255, 255); display: inline !important;" class=""><font face="Calibri, Arial, Helvetica, sans-serif" class="">Thank you,</font></span></div><div style="font-family: Helvetica; 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; text-decoration: none; font-size: 12pt;" class=""><span style="font-weight: 400; font-size: 18px; orphans: 2; widows: 2; background-color: rgb(255, 255, 255); display: inline !important;" class=""><font face="Calibri, Arial, Helvetica, sans-serif" class="">Nathan</font></span></div></div></blockquote></div><br class=""></div></body></html>