[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: Microtonal Helmholtz-Ellis notation in Lilypond: fine-tuning
From: |
Hans Aberg |
Subject: |
Re: Microtonal Helmholtz-Ellis notation in Lilypond: fine-tuning |
Date: |
Sat, 26 Sep 2009 19:35:23 +0200 |
On 25 Sep 2009, at 13:13, Stefan Thomas wrote:
How many cents are an alteration of 10/1023?
I made some Haskell functions that compute these; I use Hugs <http://haskell.org/hugs/
>, but perhaps somebody can translate it to Scheme code.
For example, for E12276, LilyPond scale degree 4 (note G relative C),
and interval ratio 3/2 (Just perfect fifth), the LilyPond alteration
ratio with offset in cents is:
LilyPond> lyalt (12276) 4 (3/2)
(10 % 1023,-3.33477112590685e-05)
Rational number ratios are written with % in Haskell, so this is
10/1023, and the second component is -3.33477112590685e-05 cents -
approximation is a bit lower than 3/2.
If one wants to know which ET is used, compute the pitch as a fraction
of an octave:
LilyPond> lyp 4 (10/1023)
7181 % 12276
As this is fraction of an octave, the denominator gives the ET: E12276.
Hans
LilyPond.hs
Description: Binary data
- Re: Microtonal Helmholtz-Ellis notation in Lilypond: fine-tuning, (continued)
- Re: Microtonal Helmholtz-Ellis notation in Lilypond: fine-tuning, Hans Aberg, 2009/09/25
- Re: Microtonal Helmholtz-Ellis notation in Lilypond: fine-tuning, Stefan Thomas, 2009/09/25
- Re: Microtonal Helmholtz-Ellis notation in Lilypond: fine-tuning, Hans Aberg, 2009/09/25
- Re: Microtonal Helmholtz-Ellis notation in Lilypond: fine-tuning, Robin Bannister, 2009/09/26
- Re: Microtonal Helmholtz-Ellis notation in Lilypond: fine-tuning, Stefan Thomas, 2009/09/26
- Re: Microtonal Helmholtz-Ellis notation in Lilypond: fine-tuning, Robin Bannister, 2009/09/26
- Re: Microtonal Helmholtz-Ellis notation in Lilypond: fine-tuning,
Hans Aberg <=
- Re: Microtonal Helmholtz-Ellis notation in Lilypond: fine-tuning, Hans Aberg, 2009/09/26
- Re: Microtonal Helmholtz-Ellis notation in Lilypond: fine-tuning, Valentin Villenave, 2009/09/26