[Audacity-nyquist] Absolute value

[Roger B. D. <rb...@cs...>]

Audacity and Nyquist are a bit out of sync, so the (latest) Nyquist
documentation describes S-ABS, S-SQRT, and some other functions that are =
not
yet available in Audacity.

I'm pretty sure Audacity's Nyquist implements S-EXP and S-LOG, making it
possible to take square roots, but an easier way to get the absolute =
value
is:

(s-max s (scale -1 s))

You could add the following to Audacity_1.0/Nyquist/dspprims.lsp:

(define s-abs (s)
  (s-max s (scale -1 s)))

And then your plug-in could use S-ABS (but then your plug-in would not =
run
elsewhere without patching dspprims.lsp or waiting for Audacity to
incorporate a newer version of Nyquist.)

	-Roger