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 <ro...@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 <d...@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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