Chords from intervals

[Mdashdotdashn]

I'm looking for a way to convert a set of intervals to the chords they make (the inverse of chord.intervals)

Instinctively I've tried tonal.chord.detect('1P 3M 5P') but it didn't work.

It looks like all the information is there but I'm not sure the api allows me to do this. Is there a clever way to do this I didn't see ?

Thanks !

[mrjacobbloom]

you could maybe do something like

function intervalsToType(input) { // input = '1P 3M 5P'
  var input_array = input.split(' '); // ['1P', '3M', '5P']
  var chordInC_array = input_array.map(int => tonal.transpose('C4', int)); // ['C4', 'E4', 'G4']
  var chordInC_string = chordInC_array.join(' '); // 'C4 E4 G4'
  var chord = tonal.chord.parse(chordInC_string); // {tonic: 'C', type: 'M'}
  return chord.type // 'M'
}

I haven't tested that but something along those lines might work

[danigb]

Thanks for the reply @mrjacobbloom :+1:

Just a note: tonal can work with arrays or strings, there's no need of conversion. So your code can be simplified to:

const input  = '1P 3M 5P'
tonal.chord.detect(tonal.harmonize(input, 'C')) // => ['CM', 'Em#5']

Edited:

or, more similar to your code:

const notes = tonal.harmonize(input, 'C');
const chord = tonal.chord.parse(notes);
return chord.type;

[mre-ableton]

Thanks !

[danigb]

Solution for tonal 1.0.0:

const intervals = ["1P", "3M", "5P"];
const chroma = Tonal.PcSet.chroma(intervals);
Tonal.chord.names(chroma); // => ["M", "Maj"]