# Tonality Mapping Question

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Greetings friends,

I have a little project I am working on - to map a two-octave scale 12-tone scale.  I want to be able to re-write pitches into this scale and to use the results in both harmonic and melodic contexts.

However, I am finding some puzzlement!

Here is a code fragment of what I am working on:

(create-tonality 12-tone-2 '(0 1 3 4 7 8 10 11 14 17 18 21))
(tonality-map '(12-tone-2 :root c4 :shift t)
'(c3 d3 e3 f3))

My thought is that it SHOULD result in:

0 1 3 4 -  c cs ds e - as the result.   Specifically: c4 cs4 ds4 e4 (or the enharmonic equivalent).

But, the result is: c eb (ds) g gs   !!   Specifically: c3 ebb g3 gs3.

Perhaps someone can help by pointing out my mistake?

With thanks,

Robert

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The output here is correct:

```(create-tonality 12-tone-2 '(0 1 3 4 7 8 10 11 14 17 18 21))
(tonality-map '(12-tone-2 :root c4 :shift t)
'(c3 d3 e3 f3))
=> (c3 eb3 g3 gs3)
```

I think the function you are looking for is:

```(integer-to-pitch '(0 1 3 4 7 8 10 11 14 17 18 21))
=> (c4 cs4 eb4 e4 g4 gs4 bb4 b4 d5 f5 fs5 a5)

(harmonic-path '(c4 cs4 eb4 e4 g4 gs4 bb4 b4 d5 f5 fs5 a5)
'(c3 d3 e3 f3))
=> (c3 cs3 eb3 e3)```

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Brilliant!  Thank you!

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Finally, part of a solution.  This tonality mapping copies the target 2-octave 12-tone collection.

The important flag seems to be :fixed t, in this application.

(setf nums '(0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21))
(setf orig (integer-to-pitch nums))
(setf map '(0 1 3 4 7 8 10 11 17 18 21))
(setf mapping (integer-to-pitch map))
(create-tonality 12T2 '(0 1 3 4 7 8 10 11 17 18 21))
(remove-duplicates (tonality-map '(12T2 :root c3 :fixed t) (integer-to-pitch nums)))

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