This program is still in early development.
Currently it is used to approximate just-intonation intervals (that, currently, you define manually editing the code) with intervals using different EDO systems. Currently you also need to set the EDO manually by setting the line.
static int edo_compare = 19;(This code was created to be easy to copy-pasted into an web site such as compilejava.net, hence you need to edit the variables manually in the code)
It is useful for composers because it lets you have a comparison between different EDO systems and a system you know (just intonation or 12-EDO).
For example: In 23-EDO hows does 2^17/23 compare with the intervals we are used to? Is it bigger than a fifth? around a minor seventh? If you run the program you might see some lines like this:
2^(17/23) = 1.6691694659381038
closest = minor sixth [8/5] 12-edo[8]
[23-edo/just] in cents[12edo] = 73.27023560396484
For comparison purposes it also adds information about the 12-edo version of the intervals. This way you can, for example, compare which system have a major third that is closer to 5/4. Is it 12-edo or 19-edo?
it compares it in two ways:
- For each of your given reference just-intervals, what is the closest EDO interval in the system you've chosen?
- For each interval in the EDO system you've picked, what is the closest just interval?
Observations:
- currently interval names are in portuguese (6ª maior = minor sixth, etc)
- we give difference in cents in 12-edo (that is, 12 semitones divided by 100 or 1200-EDO) because we are familiar with it and allows us to reasonably use our perception of a 12-edo semitone (the one we are used to) to compare. For example: in 12-EDO a perfect fifth is about 2 cents lower than 3/2. If you use 19-EDO you can use this program to find that 2^(11/19) is the closest interval to the 3/2 fifth and that it is about 7 (12-EDO) cents lower than the 3/2 fifth;
You can find an example output at 19-EDO.txt