[PD] Long long numbers

Dafydd Hughes dafydd61 at gmail.com
Sat Dec 22 08:18:02 CET 2007

I wish it was something as noble as gravitation, but it's just a clock
which counts seconds from about 30000BC to now. It's easier to do
using [mod] on the counters, but the way it's animated means it makes
a smooth transition around the dial then jumps back to 0 instead of
smoothly moving on. Just letting the rotation get bigger and bigger
without modulo eliminates this problem, but does nasty things once the
numbers get too long.

Luckily, Python can deal with much longer numbers. My solution is to
do the counting and splitting in python, then have 2 clocks in Gem
which are out of phase so one is rewinding with the gemhead off while
the other goes smoothly to 0, then they switch. There's probably a
much simpler solution.

Is any of this making sense? I'm pretty tired and I've had a couple of beers:)

Thanks everybody for the help.


On Dec 21, 2007 10:16 PM, Patrice Colet <pat at mamalala.org> wrote:
> Mathieu Bouchard a écrit :
> > On Fri, 21 Dec 2007, B. Bogart wrote:
> >
> >> I always wonder when you say large numbers and rotation...
> >>
> >> Do you really need large numbers? I never checked if its slower to
> >> rotateXYZ to 360*100 compared to rotation to 360.
> >
> > I really wonder why Dafydd wants large numbers for rotation. I thought
> > that it was for something that really needs large numbers. For all you
> > can see on a display, float32 is already much more than necessary.
> >
>   float32 is not enough for avoiding round off errors with astronomical
> values, for example if we would like to use the Newton universal
> gravitation formula,
>   F = G(m1*m2)/r^2
>   the radius would exceed the range of affordable numbers into this
> computation, and then the result wouldn't be accurate, so we can not
> simulate Newton laws with using pd arithmetic objects only.
>   Cheerfull xmas and NYear.
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