[PD] Infinite and NaN float values?

Andy Farnell padawan12 at obiwannabe.co.uk
Mon Aug 16 21:13:54 CEST 2010

On Mon, 16 Aug 2010 19:44:52 +0100
Claude Heiland-Allen <claudiusmaximus at goto10.org> wrote:

> Pd [/] guards against division by 0 by outputting 0 instead of 
> +infinity, -infinity or NotANumber (depending on the sign of the left 
> argument).
> The reason why NaN and (to a lesser extent?) infinities are discouraged 
> by non-scientific software is that it pollutes everything:

Yep, there's a few synthesis techniques like
1/1+cos(x^n) pulses and some DSF that rely on
getting a 0 instead of an inf (otherwise
you'd have to code ugly special cases
around them and it would be quite unweildy
to do in Pd).

Not sure to what extent it's still true
but NaN used to royally screw up some
versions of Jack and ALSA, requiring a complete
restart of the audio stack.


Andy Farnell <padawan12 at obiwannabe.co.uk>

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