[PD] pow/pow~ and negative input, a fix proposal

Alexandre Torres Porres porres at gmail.com
Wed May 9 21:32:46 CEST 2018

2018-05-09 15:15 GMT-03:00 Martin Peach <chakekatzil at gmail.com>:

> On Wed, May 9, 2018 at 1:13 PM, Alexandre Torres Porres <porres at gmail.com>
> wrote:
>> 2018-05-09 13:53 GMT-03:00 Martin Peach <chakekatzil at gmail.com>:
>>>> I just tried this in Max6:
>>> [pow 2] with a negative input gives a correct positive result.
>>> [pow 0.5] with negative input sets a floatnumberbox to 'nan',
>> yeah, but try it with [pow~] in max, you'll see that it will filter it
>> out and make it output "0", in the same way I was telling you about the
>> other signal objects that can generate inf/nan (I gave the example of
>> atanh~). Currently, it seems only signal bitwise operator objects in max
>> can potentially create inf/nan, and they have a [bitsafe~] object to deal
>> with that (one which we also cloned for cyclone).
> It makes sense for signal objects to give zero, to avoid giant spikes in
> the audio, but control objects are not only used for audio, they ought to
> give something more truthful, maybe just post an error message to the
> console if there is no trapping mechanism that can be constructed in a
> patch.

I get your reasoning, but this should expand to all of pd objects for
consistency, perhaps even have a way to select nan/inf... anyway... in any
case, this is not only a concern on how to update pow/pow~, there should be
a parallel and more general discussion about this, right? As far as
updating pow/pow~ goes, my suggestion/fix fits the current way Pd handles
this sort of thing.

2018-05-09 14:14 GMT-03:00 Jonathan Wilkes <jancsika at yahoo.com>:

> And how about [pow~]-- what does it do in Max?

I hope you got my other message that responded to this question. Just so it
is clear, my current Pull Request gives the exact same behaviour of pow~ in
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