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14:13:27
usha
@Shiho - did you see my new results - the one where I add hydrogen to the lysozyme system with tleap and then generate the parameters?
15:10:30
shiho
usha: Yes, I saw them. I'm working with charges, so I'll check it after that. Thank you!
17:20:41
Bike
looking at a fairly complex function, each instruction was copied 11.3 times on average
17:29:14
Bike
no obvious shape. 180 instructions were onlycopied once, 165 21 times (the max), 512 14 times (the mode)
17:33:48
Shinmera
Bike: do you know if clasp signals conditions on floating point exceptions/signals/traps?
17:36:05
Shinmera
Guess I won't have to implement float-features:with-float-traps-masked for now then
19:13:02
kpoeck
@shinmera do you have an example for a calculation where a float trap would be produced?
19:14:36
kpoeck
I see that (progn (+ most-positive-long-float most-positive-long-float) nil) works, just the printing dies
19:17:43
Shinmera
Infinities shouldn't need to be calculated. They're a precise bit value of a float.
19:20:55
kpoeck
(let ((a (/ (coerce 1 'short-float) (coerce 0.0 'short-float)))) (defconstant short-float-positive-infinity a) (defconstant short-float-negative-infinity (- a)))
19:24:59
kpoeck
In my limited experience, in clasp some traps seem to be handled gracefully, others not so great
19:25:28
kpoeck
So it would be helpfull if you could give or confirm examples where traps should occur
19:25:32
Shinmera
Well, all of the traps /should/ cause signals by default. The masking thing that float-features offers is to hush that and cause it to just ignore the float traps.
19:26:15
Shinmera
There's plenty of articles on the web that outline when fpes are caused. https://www.quora.com/What-might-be-the-possible-causes-for-floating-point-exception-error-in-C++
19:31:36
kpoeck
Well according to this, i'd expect (+ most-positive-long-float most-positive-long-float) to cause a trap
19:39:45
Shinmera
Afaiu you need to instruct the CPU's FPU which things should cause exceptions, so some things might also just not be enabled.
19:41:26
kpoeck
Unfortunately my buddy UNDEFINED-FUNCTION (:NAME INLINED-TWO-ARG-/) failed, so I have to recompile all cclasp
19:43:47
kpoeck
and waf now compiles nearly everything from scratch, this build system needs some tender care
20:48:52
kpoeck
(+ most-positive-long-float most-positive-long-float) -> #.ext:double-float-positive-infinity