<div dir="ltr"><span style="font-family:arial,sans-serif;font-size:13px">One thing to note is that we would like to have an additional mixed precision scheme, hopefully in 5.0. The idea is that part of the code, like force calculations, would run in single precision with fixed precision accumulators/reduction and </span><span style="font-family:arial,sans-serif;font-size:13px">double</span><span style="font-family:arial,sans-serif;font-size:13px"> for whatever it makes sense/is useful. Using real everywhere could make achieving this quite difficult, right?</span><br>
</div><div class="gmail_extra"><br clear="all"><div>--<br>Szilárd</div>
<br><br><div class="gmail_quote">On Mon, Feb 25, 2013 at 3:50 PM, Mark Abraham <span dir="ltr"><<a href="mailto:mark.j.abraham@gmail.com" target="_blank">mark.j.abraham@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
I'm not aware of a need to change the way we implement this.<div><br></div><div>Berk and I have mooted the desirability of switching our naming scheme to "double-" vs "mixed-precision" on the grounds that aspects of the virial computation have been in double precision for a long time. We may as well avoid people leaping to the conclusion that "single-precision" GROMACS must be dodgy because you need double precision for some aspects of the algorithm.<span class="HOEnZb"><font color="#888888"><br>
<br>Mark</font></span></div><div class="HOEnZb"><div class="h5"><div><br><div class="gmail_quote">On Sun, Feb 24, 2013 at 10:09 PM, David van der Spoel <span dir="ltr"><<a href="mailto:spoel@xray.bmc.uu.se" target="_blank">spoel@xray.bmc.uu.se</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Hi,<br>
<br>
did we decide on how to treat real variables in C++?<br>
There is nothing stopping us from keeping the same<br>
<br>
#ifdef GMX_DOUBLE<br>
typedef double real;<br>
#else<br>
typedef float real;<br>
#endif<br>
<br>
that we have use for decades. Or is there reason to change it?<br>
<br>
Cheers,<span><font color="#888888"><br>
-- <br>
David van der Spoel, Ph.D., Professor of Biology<br>
Dept. of Cell & Molec. Biol., Uppsala University.<br>
Box 596, 75124 Uppsala, Sweden. Phone: <a href="tel:%2B46184714205" value="+46184714205" target="_blank">+46184714205</a>.<br>
<a href="mailto:spoel@xray.bmc.uu.se" target="_blank">spoel@xray.bmc.uu.se</a> <a href="http://folding.bmc.uu.se" target="_blank">http://folding.bmc.uu.se</a><br>
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