User:Holger Stoltenberg/sandbox: Difference between revisions

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<span id="example01"></span>
<span id="example01"></span>
<u>Example 1</u>: A just major third relates the first element ''(m=1)'' of a Mode 4 ''(n=4)'' overtone scale to the tonic ''(m=0)'' of Mode 4 and we get  
<u>Example 1</u>: A just major third relates the first element ''(m=1)'' of a Mode 4 ''(n=4)'' overtone scale to the tonic ''(m=0)'' of Mode 4 and we get


::::<math>
::::<math>
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[[#example01|Example 1]]) has an intonation interval of -14 ¢, which represents the ''distance to the nearest vertical 12edo line''. (Note that we generally evaluate intonation beginning at the 12edo pitch. This results in a minus sign for the intonation of the upper note of a just a third.)
[[#example01|Example 1]]) has an intonation interval of -14 ¢, which represents the ''distance to the nearest vertical 12edo line''. (Note that we generally evaluate intonation beginning at the 12edo pitch. This results in a minus sign for the intonation of the upper note of a just a third.)


To calculate the intonation
==== Calculate intonation ====
To calculate the signed intonation interval


*compute the ''remainder'' of the interval’s ''value in cents'' by a modulo division (386 ¢ ''mod''100), the <br>intermediate result is 86 ¢
*compute the ''remainder'' of the original interval’s ''value in cents'' by a modulo division <small><math>(386</math> ¢ <math>mod(100))</math></small>, the <br>intermediate result is 86 ¢
*Test: If the intermediate result is greater than 50 ¢ then subtract 100 ¢
*Test: If the intermediate result is greater than 50 ¢ then subtract 100 ¢
*The test is true and the final result is 86 ¢ -100 ¢ = -14 ¢
*The test is true and the final result is 86 ¢ -100 ¢ = -14 ¢
To determine the 12edo interval the intonation is applied to, get the original interval ''r<sub>cents </sub>'' and do some integer arithmetic:
 
==== Determine the nearest 12edo interval ====
To determine the nearest 12edo interval the intonation is applied to, get the original interval ''r<sub>cents </sub>'' and do some integer arithmetic:
::::<math>
::::<math>
r_{12edo}=integer\left (\frac{r_{cents}+50c}{100.0}  \right )\cdot 100</math> <br>
r_{12edo}=integer\left (\frac{r_{cents}+50c}{100.0}  \right )\cdot 100</math> <br>