[PD] Infinite and NaN float values?

Matteo Sisti Sette matteosistisette at gmail.com
Mon Aug 16 19:59:45 CEST 2010


I've found out that making a float grow and grow and grow it eventually 
reaches a value that is displayed in number boxes as "+Inf".

Then if I multiply that number by 0 I get a value that is displayed in a 
number box as "NaN".

Is this expected behaviour? If so i guess infinities and NaN have been 
recently introduced, haven't they?

However there seem to be some inconsistency: 5/4 returns 0 (as I was 
used to), not +inf. Also, I'm not sure +inf is the value you expect when 
adding something to the greatest representable value... or is it?

Also I cannot seem to find a way to write inf's or NaN as a literal (in 
a message box), and I cannot find an [isNaN] or similar object... that's 
why I wonder if this is a feature or a bug.

Also, sliders seem not to like them.

If you feed a NaN (or maybe +Inf, I'm not sure) to a slider, it makes 
the cursor disappear (which is probably OK for NaN), but then you 
suddenly get weird behaviour of the window: a scrollbar with a very 
small cursor appears as if the patch window had become suddenly huge and 
it may scroll away so you cannot see the patch content any more and you 
may not be able to scroll it.

It seems like it is actually trying to draw the slider's cursor far 
away, which doesn't happen with huge but finite numbers....

I'm trying to build a simple test patch, but I'm having difficulties.
I can reproduce it with a patch that is pretty simple but doesn't quite 
isolate the "issue" (or non-issue) in a decent way.
I'll post it if I cannot end up with anything better


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