♫ TRANSPOSE ANY CHORD ♯♭♮
Description
ChordTransposer.transpose(chord, transpose_steps, flat_or_sharp) will take any chord (even fancy complex jazz chords) and transpose it by any number of steps with the desired sharp or flat notation.
Install
npm i every-chord-transposer
import ChordTransposer from 'every-chord-transposer/chord_transposer.js';
var transposedChord = ChordTransposer.transpose("Cmaj7b5", 1, "#");
console.log(transposedChord); // C#maj7b5
package.json
{
"dependencies": {
"every-chord-transposer": "^..."
},
"type": "module"
}
Parameters
chord: string of the chord, e.g. "C#maj7"
transpose_steps: integer (positive or negative), e.g. 1, -4, 2, 0
flat_or_sharp: either "♭", "♯" or "flat", "sharp", or "b", "#", or 0, "0", or "♮"
► If ChordTransposer.transpose(...) is called with only the chord parameter, it will return the chord unchanged.
► If ChordTransposer.transpose(...) is called with only the chord and transpose_steps parameter, it will return the chord transposed by the number of steps with the same sharp or flat symbol derived from the original chord.
► If ChordTransposer.transpose(...) is called with only the chord and flat_or_sharp parameter,it will return the chord adjusted to the desired sharp or flat symbol.
►►► ChordTransposer.transpose(...) will assume, depending on the parameters, whether the second parameter is transpose_steps or flat_or_sharp.
► ChordTransposer.transpose(...) makes sure, that only the relevant sharp or flat symbol is changed, e.g. ChordTransposer.transpose("C♯maj7b5", 2, "#") will return "D#maj7b5" and not "D#maj7#5".
Usage (Check usage_example.js file):
import ChordTransposer from './chord_transposer.js';
// import ChordTransposer from 'every-chord-transposer/chord_transposer.js'; // if installed via npm i every-chord-transposer
// One parameter (chord) -> returns same chord
var transposedChord = ChordTransposer.transpose("C#");
console.log(transposedChord); // C#
// Two parameters (chord, transpose_steps) -> returns chord transposed by transpose_steps
// and DERIVES sharp or flat based on orginal chord
transposedChord = ChordTransposer.transpose("F#", 2);
console.log(transposedChord); // G#
transposedChord = ChordTransposer.transpose("Eb", -5);
console.log(transposedChord); // Bb
transposedChord = ChordTransposer.transpose("Eb", 0);
console.log(transposedChord); // Eb
// Two parameters (chord, flat_or_sharp) -> returns chord adjusted to flat or sharp
transposedChord = ChordTransposer.transpose("Eb", "#");
console.log(transposedChord); // D#
transposedChord = ChordTransposer.transpose("F#", "b");
console.log(transposedChord); // Gb
transposedChord = ChordTransposer.transpose("F#", "0");
console.log(transposedChord); // F#
// Three parameters (chord, transpose_steps, flat_or_sharp) -> returns chord
// transposed by transpose_steps and adjusted to flat or sharp
transposedChord = ChordTransposer.transpose("F#", 2, "b");
console.log(transposedChord); // Ab
transposedChord = ChordTransposer.transpose("Eb", -5 , "b");
console.log(transposedChord); // Bb
transposedChord = ChordTransposer.transpose("Fmaj7", 1 , "#");
console.log(transposedChord); // F#maj7
transposedChord = ChordTransposer.transpose("C♯maj7b5", 2, "♯");
console.log(transposedChord); // D#maj7b5
transposedChord = ChordTransposer.transpose("G13(♭9♯11)", -1, "b");
console.log(transposedChord); // Gb13(b9#11)
transposedChord = ChordTransposer.transpose("Bb/C#", -2, "b");
console.log(transposedChord); // Ab/B