Using this expression

(harmonics 'a2 8 :quantize nil :type :hertz)

I am getting

(110.0 220.0 329.62756 440.0 546.4174 659.2551 772.751 880.0)

but I am expecting

(110.0 220.0 330.0 440.0 550.0 660.0 770.0 880.0)

What am I understanding wrong?

Best, Achim

(setf harm (harmonics 'a2 8 :quantize 1/2 :type :hertz))
=> (110.0 220.0 329.62756 440.0 554.3653 659.2551 783.99085 880.0)

(hertz-to-pitch harm)
=> (a2 a3 e4 a4 cs5 e5 g5 a5)

(hertz-to-pitch '(110.0 220.0 330.0 440.0 550.0 660.0 770.0 880.0))
=> (a2 a3 e4 a4 c5.. e5 fs5.. a5)

What is quantize NIL doing?

49 minutes ago, born said:

What is quantize NIL doing?

Nothing.

Jesper

:quantize nil
(110.0 220.0 329.62756 440.0 546.4174 659.2551 772.751 880.0)

:quantize 1/2
(110.0 220.0 329.62756 440.0 554.3653 659.2551 783.99085 880.0)

not exactly the same numbers ...
question remains.

Your first example doesn't quantize, and your second example quantizes to the closest semitone, I guess.

Sorry, didn't read carefully enough in my deleted answer.

Jesper

Sorry to insist in this, but my first example is somehow quantizing because the result should be
(110.0 220.0 330.0 440.0 550.0 660.0 770.0 880.0)

when calculating a harmonic scale in frequencies and not
(110.0 220.0 329.62756 440.0 546.4174 659.2551 772.751 880.0)

Achim

Only Janusz knows.

Could it be that the default is a tempered scale?

(harmonics 'a2 8 :quantize nil :type :hertz)

=>(110.0 220.0 329.62756 440.0 546.4174 659.2551 772.751 880.0)

(* 220 (expt 2 7/12)) ;;tempered fifth

=>329.62756

Jesper