The file format used in all True Series apps is very similar to the format used in Scala. The rules are a few but quite simple.
- The files are human readable text-files.
- There is one scale per file.
- Lines beginning with an exclamation mark are regarded as comments and are to be ignored.
- The first (non comment) line contains a short description of the scale. The description is only one line. An empty line is regarded as an error and will be rejected.
- The second line contains 4 character long identifier, which is has to be unique within the set of defined temperaments. It is up to you as a user to honour this rule.
- After that come the pitch values, each on a separate line, either as a ratio or as a value in cents. If the value contains a period, it is a cents value, otherwise a ratio. Ratios are written with a slash, and only one. Integer values with no period or slash should be regarded as such, for example “2” should be taken as “2/1″. Anything after a valid pitch value should be ignored. Space or horizontal tab characters are allowed and should be ignored. Negative ratios are meaningless and should give a read error.
- The first note of 1/1 or 0.0 cents is implicit and not in the files.
- The last note is always 2/1 or 1200.0 cents in the files.
- Files which are incorrectly formatted result in a ‘error in file format’ and are rejected.
As an example, Maria Renold’s “Scale of Twelve Fifths” will illustrate the temperament file format.