[racket] "error: degrees->complex: 360.0"

Interesting, my code has the same bug then.  I called it modulo/real, used
for things like displaying the space ship's rotation to the user or
wrapping x coordinates to stay in the world.  Apparently it's going to fail
at some point with vector ref out of range.  What was your fix?  I was
thinking to just clamp explicitly like mod/real = (max 0 (min
the-mod-minus-1 (old-modulo/real x)))


On Mon, May 12, 2014 at 11:12 PM, Robby Findler <robby at eecs.northwestern.edu
> wrote:

> Right. Probably there is a better fix, but the essential problem, as I
> understand it, is that there are more floating points between 0 and 1
> than between any two other integers and the code made the assumption
> that that didn't happen....
>
> The basic desire is to turn a real number into a number in [0,360)
> such that the result represents the same number in degrees but is
> normalized somehow.
>
> Robby
>
> On Mon, May 12, 2014 at 10:06 PM, Danny Yoo <dyoo at hashcollision.org>
> wrote:
> > Wow.  Floating point really is nasty.  I see how it might have happened
> now.
> >
> > ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
> >> -0.0000000000000001
> > -1e-16
> >> (+ 360 -1e-16)
> > 360.0
> >>
> > ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
>
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