From: Cody P. <cod...@gm...> - 2012-07-26 21:35:58
|
On Thu, Jul 26, 2012 at 3:25 PM, Roy Stogner <roy...@ic...>wrote: > > On Thu, 26 Jul 2012, Roy Stogner wrote: > > > I do like the idea of keeping this as a debug-mode check, but in that > > case, could we just check for 0 directly rather than with that weird > > "abs-less-than-min" construction, even in the Number==Real case? > > Alternatively, we could go nuts: in the LibMeshInit constructor, use > fegetenv()/fesetexceptflag()/fesetenv() to turn on hardware floating > point exceptions, for every arithmetic operation, everywhere. That > ought to be more efficient per-test, in both software and speed, than > using if(); and it ought to be much more thorough. > Yeah we take a mixed approach in our software, We have a small set of utility functions that we call to toggle the hardware flags but only in Debug mode. We wrap routines of interest with calls to those utility functions. The code for Mac/Linux is quite different for turning these flags on/off so let us know if you decide to go this direction. We can supply the Apple system calls as needed. > > I don't think I'd want this on by default (see the previous discussion > re: Ben and applications relying on NaN tests) but it might be a nice > command-line option. Yes agreed, probably not the desired default behavior. Cody > --- > Roy > > > ------------------------------------------------------------------------------ > Live Security Virtual Conference > Exclusive live event will cover all the ways today's security and > threat landscape has changed and how IT managers can respond. Discussions > will include endpoint security, mobile security and the latest in malware > threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ > _______________________________________________ > Libmesh-users mailing list > Lib...@li... > https://lists.sourceforge.net/lists/listinfo/libmesh-users > |