<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "> <div> Run with -ts_view it is likely running with the default explicit method Euler which requires no solver and hence no preconditioner. You need to use an implicit method if you want to use it with a preconditioner.</div><div><br></div><div> Barry</div><div><br><div><div>On Jun 28, 2010, at 3:27 PM, Xuan YU wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><br><div><div>On Jun 28, 2010, at 4:17 PM, Barry Smith wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div><br>On Jun 28, 2010, at 3:13 PM, Xuan YU wrote:<br><br><blockquote type="cite"><br></blockquote><blockquote type="cite">On Jun 28, 2010, at 3:47 PM, Barry Smith wrote:<br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite"><blockquote type="cite"><br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"> Do you have a TSSetFromOptions() or a SNESSetFromOptions() or a KSPSetFromOptions() or a PCSetFromOptions(). If not then the option never gets processed and used.<br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><br></blockquote></blockquote><blockquote type="cite">I only have ierr = TSSetFromOptions(ts);CHKERRQ(ierr).<br></blockquote><br> That is fine, that calls PCSetFromOptions() and should process your option. Perhaps you set a prefix for the TS that you need in setting the preconditioner type.<br><br></div></blockquote>This is the petsc code:<br><div><div> ierr = TSCreate(PETSC_COMM_WORLD,&ts);CHKERRQ(ierr);</div><div> ierr = TSSetProblemType(ts,TS_NONLINEAR);CHKERRQ(ierr);</div><div> ierr = TSMonitorSet(ts,Monitor,&appctx,PETSC_NULL);CHKERRQ(ierr);</div><div> ierr = TSSetSolution(ts,CV_Y);CHKERRQ(ierr);</div><div> ierr = TSSetRHSFunction(ts,f,&appctx);CHKERRQ(ierr);</div><div> ierr = TSSetInitialTimeStep(ts,0,1.0);CHKERRQ(ierr);</div><div> ierr = TSSetDuration(ts,cData.EndTime,cData.EndTime);CHKERRQ(ierr);</div><div> ierr = TSSetFromOptions(ts);CHKERRQ(ierr);</div><div> ierr = TSSetUp(ts);CHKERRQ(ierr);</div><div> ierr = TSStep(ts,&its,&ftime);CHKERRQ(ierr);</div><div> ierr = VecDestroy(CV_Y);CHKERRQ(ierr);</div><div> ierr = TSDestroy(ts);CHKERRQ(ierr);</div><div> ierr = PetscFinalize();CHKERRQ(ierr);</div><div><br></div></div><div><br></div><br><blockquote type="cite"><div> Barry<br><br><blockquote type="cite"><br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite"><blockquote type="cite"> Barry<br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite">On Jun 28, 2010, at 2:24 PM, Xuan YU wrote:<br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">Hi,<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite"><br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">I run my code by ./xxx -pc_type icc<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite"><br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">But it says:<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite"><br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">WARNING! There are options you set that were not used!<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">WARNING! could be spelling mistake, etc!<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">Option left: name:-pc_type value: icc<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite"><br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">Could you please tell me what happened?<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite"><br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">Xuan YU<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite"><a href="mailto:xxy113@psu.edu">xxy113@psu.edu</a><br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite"><br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite"><br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite"><br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite"><br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><br></blockquote></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite"><br></blockquote><br><br></div></blockquote></div><br><div apple-content-edited="true"> <div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><span class="Apple-style-span" style="border-collapse: separate; font-family: Helvetica; font-size: medium; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div>Xuan YU (<span class="Apple-style-span" style="font-family: arial; font-size: 16px; white-space: pre; ">俞烜<span class="Apple-style-span" style="font-family: Helvetica; font-size: medium; white-space: normal; ">)</span></span></div><div><a href="mailto:xxy113@psu.edu">xxy113@psu.edu</a></div><div><br></div></div></span><br class="Apple-interchange-newline"></div><br class="Apple-interchange-newline"> </div><br></div></blockquote></div><br></div></body></html>