<div dir="ltr"><br><div class="gmail_extra"><br><div class="gmail_quote">On Thu, Jun 30, 2016 at 8:48 PM, Jeff Hammond <span dir="ltr"><<a href="mailto:jeff.science@gmail.com" target="_blank">jeff.science@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><span class=""><span style="color:rgb(80,0,80)">> The default settings often don’t work well for 3D problems.</span><div><font color="#500050"><br></font></div></span><div><font color="#500050">Are 2D (1D?) problems really the common case for PDE solvers? Aren't interesting problems 3D? Shouldn't the defaults be set to optimize for 3D?</font></div></div></blockquote><div><br></div><div>Lots of people do 2D in production (it might just be part of a larger 3D algorithm like the XGC code).</div><div><br></div><div>Also 2D is useful for debugging, regression, incremental development.</div><div><br></div><div>I would prefer that hypre's defaults be for 3D and I like Barry's suggestion of changing the default with the dimension. We can get a shot at the dimension, without any API changes, by just inferring from the block size. Better than nothing. But I do find it annoying to search around for my 3D hypre parameters when I'm (customers) doing a 3D problems. I am sure lots of cycles are wasted by PETSc users using hypre in 3D with the defaults.</div><div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><span class="HOEnZb"><font color="#888888"><div><font color="#500050"><br></font></div></font></span><div><span class="HOEnZb"><font color="#888888"><font color="#500050">Jeff<br></font></font></span><span class=""><div class="gmail_extra"><div><br></div>-- <br><div data-smartmail="gmail_signature">Jeff Hammond<br><a href="mailto:jeff.science@gmail.com" target="_blank">jeff.science@gmail.com</a><br><a href="http://jeffhammond.github.io/" target="_blank">http://jeffhammond.github.io/</a></div>
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