[racket-dev] .1 evaluates to 0.0 [was Re: plot doesn't plot (inexact->exact: no exact representation for +nan.0)]

From: Neil Toronto (neil.toronto at gmail.com)
Date: Wed Jan 11 10:35:37 EST 2012

On 01/11/2012 06:32 AM, Marijn wrote:
> It looks like there is still a residual bug though, that causes the
> stairs function when zoomed in to have non-vertical parts as you can see
> in the screenshot, though I can reproduce it also with the C locale, so
> looks like a genuine plot library bug this time. Although I am surprised
> at that too, since Neil looked at a similar screenshot by me earlier
> which also showed this problem. Forgot to push the fix for this Neil?

Actually, I just haven't fixed it. I have yet to find the exact spot 
that flonums can sneak through without getting converted to rationals.

Compared to other things, it has been rather low priority, as it seems 
to require zooming way into the plot of an inexact function. I've mostly 
been concerned with proper rendering when zoomed into the plots of exact 

Still, it excites my inner analysis nerd to no end to make plot correct 
in the limit, even on functions with finite resolution. I have my own 
test case for it, and it will be fixed.

Neil T

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