Re: [avr-libc-dev] Some question regarding FP-math

[Weddington, Eric]

Hi Dr. Klein,

Yes, this is the right place to ask those questions. However, avr-libc has had 
"on-again, off-again" maintenance for its floating point library code, with 
different maintainers over the years.

If you see a place where you are willing to help out, we would certainly 
welcome the help...

Eric Weddington

> -----Original Message-----
> From: address@hidden [mailto:avr-
> address@hidden On Behalf Of Dr.
> Alexander Klein
> Sent: Monday, June 18, 2012 1:53 AM
> To: address@hidden
> Subject: [avr-libc-dev] Some question regarding FP-math
> 
> Hello,
> 
> I just got myself an Arduino-board to evaluate some algorithms in a more real-
> world like environment than I get with the "slowest Atom-Netbook around"
> approach. I usually prototype the algorithms in GNU-Octave, so I wondered what
> errors I'd have to expect compared to IEEE double precision math.
> 
> So, just for the fun of it, I started browsing the source of the FP-
> implementation and a few things occured to me:
> 
> 1. Most if not all transcendental functions are implemented as power series
> approximations, but no hints are given as to their properties of
> approximation. Are the polynomials or maybe their derivatives optimal in any
> L_p-sense? Can a description be found anywhere?
> 
> 2. All we have for the time being is single precision float. Are the functions
> for power series evaluation optimised so as to minimise summation error?
> 
> 3. In an old post (http://lists.nongnu.org/archive/html/avr-libc-dev/2006-
> 04/msg00068.html) someone benchmarked basic arithmetic operations, but only
> for one platform. How do other platforms perform? Especially, would it be
> worthwhile to try to speed up multiplication?
> 
> I hope this is the right place to ask these questions anyway ...
> 
> Kind regards,
> 
>       Alex
> 
> --
> Dr. Alexander Klein, Diplom-Mathematiker
> Physiologisches Institut der JLU-Gießen
> Aulweg 129
> 35392 Gießen
> 
> http://www.med.uni-giessen.de/physio/
> 
> 
> _______________________________________________
> AVR-libc-dev mailing list
> address@hidden
> https://lists.nongnu.org/mailman/listinfo/avr-libc-dev