[PD] dbtorms + friends and negative dB values

[Mathieu Bouchard]

On Tue, 9 Nov 2010, Matthias Blau wrote:

> is there any specific reason why dbtorms and friends do not take dB 
> values <=0 as input?

Why ask the question, when it's not going to change, and when you can do :

   [expr pow(10, ($f1-100)/20)] instead of [dbtorms]
   [expr log10($f1)*20+100]     instead of [rmstodb]

That's all.

> Kind of reminds one of the Total Ozone Mapping Spectrometer (TOMS) bug 
> http://earthobservatory.nasa.gov/Features/RemoteSensingAtmospher/remote_sensing5.php 
> which is frequently ranked among the top 10 historical software bugs 
> with extreme consequences: It made NASA unaware of the antarctic hole in 
> the ozone layer for years simply because the analysis software ignored 
> ozone values below a certain threshold...

I don't know, it might be some kind of denormalophobia, that is, fear 
induced by stupid stuff that looks like a bug in the Pentium 4.

> So please pd developers, change this or give a good reason for not 
> taking lessons from history.

For the most part, for internals classes such as [dbtorms], there isn't 
«pd developers», there's Miller and that's all. I don't expect [dbtorms] 
to change.

However, you could make an externals library that reregisters those two 
names with different formulas. Unfortunately, abstractions are still not 
allowed to take over names (without the help of a specially-crafted 
externals).

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| Mathieu Bouchard ---- tél: +1.514.383.3801 ---- Villeray, Montréal, QC