teoria/lib/knowledge.js

Music theory for JavaScript

// Note coordinates [octave, fifth] relative to C
module.exports = {
  notes: {
    c: [0, 0],
    d: [-1, 2],
    e: [-2, 4],
    f: [1, -1],
    g: [0, 1],
    a: [-1, 3],
    b: [-2, 5],
    h: [-2, 5]
  },

  intervals: {
    unison: [0, 0],
    second: [3, -5],
    third: [2, -3],
    fourth: [1, -1],
    fifth: [0, 1],
    sixth: [3, -4],
    seventh: [2, -2],
    octave: [1, 0]
  },

  intervalFromFifth: ['second', 'sixth', 'third', 'seventh', 'fourth',
                         'unison', 'fifth'],

  intervalsIndex: ['unison', 'second', 'third', 'fourth', 'fifth',
                      'sixth', 'seventh', 'octave', 'ninth', 'tenth',
                      'eleventh', 'twelfth', 'thirteenth', 'fourteenth',
                      'fifteenth'],

// linear index to fifth = (2 * index + 1) % 7
  fifths: ['f', 'c', 'g', 'd', 'a', 'e', 'b'],
  accidentals: ['bb', 'b', '', '#', 'x'],

  sharp: [-4, 7],
  A4: [3, 3],

  durations: {
    '0.25': 'longa',
    '0.5': 'breve',
    '1': 'whole',
    '2': 'half',
    '4': 'quarter',
    '8': 'eighth',
    '16': 'sixteenth',
    '32': 'thirty-second',
    '64': 'sixty-fourth',
    '128': 'hundred-twenty-eighth'
  },

  qualityLong: {
    P: 'perfect',
    M: 'major',
    m: 'minor',
    A: 'augmented',
    AA: 'doubly augmented',
    d: 'diminished',
    dd: 'doubly diminished'
  },

  alterations: {
    perfect: ['dd', 'd', 'P', 'A', 'AA'],
    minor: ['dd', 'd', 'm', 'M', 'A', 'AA']
  },

  symbols: {
    'min': ['m3', 'P5'],
    'm': ['m3', 'P5'],
    '-': ['m3', 'P5'],

    'M': ['M3', 'P5'],
    '': ['M3', 'P5'],

    '+': ['M3', 'A5'],
    'aug': ['M3', 'A5'],

    'dim': ['m3', 'd5'],
    'o': ['m3', 'd5'],

    'maj': ['M3', 'P5', 'M7'],
    'dom': ['M3', 'P5', 'm7'],
    'ø': ['m3', 'd5', 'm7'],

    '5': ['P5']
  },

  chordShort: {
    'major': 'M',
    'minor': 'm',
    'augmented': 'aug',
    'diminished': 'dim',
    'half-diminished': '7b5',
    'power': '5',
    'dominant': '7'
  },

  stepNumber: {
    'unison': 1,
    'first': 1,
    'second': 2,
    'third': 3,
    'fourth': 4,
    'fifth': 5,
    'sixth': 6,
    'seventh': 7,
    'octave': 8,
    'ninth': 9,
    'eleventh': 11,
    'thirteenth': 13
  },

  // Adjusted Shearer syllables - Chromatic solfege system
  // Some intervals are not provided for. These include:
  // dd2 - Doubly diminished second
  // dd3 - Doubly diminished third
  // AA3 - Doubly augmented third
  // dd6 - Doubly diminished sixth
  // dd7 - Doubly diminished seventh
  // AA7 - Doubly augmented seventh
  intervalSolfege: {
    'dd1': 'daw',
    'd1': 'de',
    'P1': 'do',
    'A1': 'di',
    'AA1': 'dai',
    'd2': 'raw',
    'm2': 'ra',
    'M2': 're',
    'A2': 'ri',
    'AA2': 'rai',
    'd3': 'maw',
    'm3': 'me',
    'M3': 'mi',
    'A3': 'mai',
    'dd4': 'faw',
    'd4': 'fe',
    'P4': 'fa',
    'A4': 'fi',
    'AA4': 'fai',
    'dd5': 'saw',
    'd5': 'se',
    'P5': 'so',
    'A5': 'si',
    'AA5': 'sai',
    'd6': 'law',
    'm6': 'le',
    'M6': 'la',
    'A6': 'li',
    'AA6': 'lai',
    'd7': 'taw',
    'm7': 'te',
    'M7': 'ti',
    'A7': 'tai',
    'dd8': 'daw',
    'd8': 'de',
    'P8': 'do',
    'A8': 'di',
    'AA8': 'dai'
  }
};