Where to copy and paste Nyquist codes?

I saw this code made by @steve in a 2015 forum, where they made a code that fades out/in(?) EQ, but i’m not sure how to use it. I tried typing it into Nyquist Prompt(is that where you even put it?) and messed around with it. I can’t get to do anything(except error 0s). I am definitely doing something wrong but not sure how to make it work.
Here is steve’s code

(setq start-freq 10000) ; cannot be greater than 1/2 the sample rate
(setq end-freq 100)
(setq passes 4)         ; more passes for a steeper filter cut-off
(setq sweep-type 0)     ; 1 for a linear sweep, 0 for exponential sweep

(let* ((nyq (/ *sound-srate* 2.0))
       (f0 (max 0 (min nyq start-freq)))
       (f1 (max 0 (min nyq end-freq))))
  (if (= sweep-type 0)
      (setf hpfreq (pwev f0 1 f1))
      (setf hpfreq (pwlv f0 1 f1)))
  (dotimes (i passes s)
    (setf s (hp s hpfreq))))

Thanks for looking

~decade-old Nyquist code is not compatible with the latest version of Audacity.

I added “code tags” (</>) to the code that you posted so that it would display correctly.

To make that old code compatible with current versions of Audacity, you need to add ;version 3 at the top like this:

;version 3
(setq start-freq 10000) ; cannot be greater than 1/2 the sample rate
(setq end-freq 100)
(setq passes 4)         ; more passes for a steeper filter cut-off
(setq sweep-type 0)     ; 1 for a linear sweep, 0 for exponential sweep

(let* ((nyq (/ *sound-srate* 2.0))
       (f0 (max 0 (min nyq start-freq)))
       (f1 (max 0 (min nyq end-freq))))
  (if (= sweep-type 0)
      (setf hpfreq (pwev f0 1 f1))
      (setf hpfreq (pwlv f0 1 f1)))
  (dotimes (i passes s)
    (setf s (hp s hpfreq))))

The code can then be used in the “Nyquist Prompt”.

Good to know

Ok thanks a ton

Also is there a way to make it less treble to normal instead of less bass to normal?