Module lib.musicutil
Music utility module.
Utility methods for working with notes, scales and chords. The norns script reference has examples for this module.
Info:
- Release: v1.1.2
- Author: Mark Eats
Functions
| generate_scale (root_num, scale_type[, octaves]) | Generate scale from a root note. |
| generate_scale_of_length (root_num, scale_type, length) | Generate given number of notes of a scale from a root note. |
| generate_chord (root_num, chord_type[, inversion]) | Generate chord from a root note. |
| generate_chord_roman (root_num, scale_type, roman_chord_type) | Generate a chord using Roman chord notation for a given root note and scale. |
| generate_chord_scale_degree (root_num, scale_type, degree[, seventh]) | Generate a chord from a scale degree, for a given root note and key, using the system of tonal harmony from the European common-practice period. |
| chord_types_for_note (note_num, key_root, key_type) | List chord types for a given root note and key. |
| snap_note_to_array (note_num, snap_array) | Snap a MIDI note number to the nearest note number in an array. |
| snap_notes_to_array (note_nums_array, snap_array) | Snap an array of MIDI note numbers to an array of note numbers. |
| note_num_to_name (note_num[, include_octave]) | Return a MIDI note number's note name. |
| note_nums_to_names (note_nums_array[, include_octave]) | Return an array of MIDI note numbers' names. |
| note_num_to_freq (note_num) | Return a MIDI note number's frequency. |
| note_nums_to_freqs (note_nums_array) | Return an array of MIDI note numbers' frequencies. |
| freq_to_note_num (freq) | Return a frequency's nearest MIDI note number. |
| freqs_to_note_nums (freqs_array) | Return an array of frequencies' nearest MIDI note numbers. |
| interval_to_ratio (interval) | Return the ratio of an interval. |
| intervals_to_ratios (intervals_array) | Return an array of ratios of intervals. |
| ratio_to_interval (ratio) | Return the interval of a ratio. |
| ratios_to_intervals (ratios_array) | Return an array of intervals of ratios. |
Functions
- generate_scale (root_num, scale_type[, octaves])
-
Generate scale from a root note.
Parameters:
- root_num integer MIDI note number (0-127) where scale will begin.
- scale_type string String defining scale type (eg, "major", "aeolian" or "neapolitan major"), see class for full list.
- octaves integer Number of octaves to return, defaults to 1. (optional)
Returns:
-
{integer...}
Array of MIDI note numbers.
- generate_scale_of_length (root_num, scale_type, length)
-
Generate given number of notes of a scale from a root note.
Parameters:
- root_num integer MIDI note number (0-127) where scale will begin.
- scale_type integer String defining scale type (eg, "major", "aeolian" or "neapolitan major"), see class for full list.
- length integer Number of notes to return, defaults to 8.
Returns:
-
{integer...}
Array of MIDI note numbers.
- generate_chord (root_num, chord_type[, inversion])
-
Generate chord from a root note.
Parameters:
- root_num integer MIDI note number (0-127) for chord.
- chord_type string String defining chord type (eg, "major", "minor 7" or "sus4"), see class for full list.
- inversion integer Number of chord inversion. (optional)
Returns:
-
{integer...}
Array of MIDI note numbers.
- generate_chord_roman (root_num, scale_type, roman_chord_type)
-
Generate a chord using Roman chord notation for a given root note and scale.
This function can return notes that are outside the scale and will not try to resolve ambiguous notation with
context.
See chord_types_for_note or generate_chord_scale_degree if you want to constrain chords to in-scale pitches.
See MusicUtil.SCALES for the supported scale types and MusicUtil.CHORDS for the chords that can be returned.
Parameters:
- root_num integer MIDI note number (0-127) defining the key.
- scale_type string String defining scale type (eg, "Major", "Dorian".)
- roman_chord_type string Roman-numeral-style string defining chord type (eg, "V", "iv7" or "III+") including limited bass notes (e.g. "iv6-9") and lowercase-letter inversion notation (e.g. "IIb" for first inversion)
Returns:
-
{integer...}
Array of MIDI note numbers.
- generate_chord_scale_degree (root_num, scale_type, degree[, seventh])
-
Generate a chord from a scale degree, for a given root note and key, using the
system of tonal harmony from the European common-practice period.
See MusicUtil.SCALECHORDDEGREES for the specific chords assigned to each degree.
Parameters:
- root_num integer MIDI note number (0-127) defining the key.
- scale_type string String defining scale type. Not all scales are supported; valid values are "Major" (or "Ionian"), "Natural Minor" (or "Minor" or "Aeolian"), "Harmonic Minor", "Melodic Minor", "Dorian", "Phrygian", "Lydian", "Mixolydian", or "Locrian".
- degree integer Number between 1-7 selecting the degree of the chord.
- seventh boolean Return the 7th chord if set to true (optional) (optional)
Returns:
-
{integer...}
Array of MIDI note numbers.
- chord_types_for_note (note_num, key_root, key_type)
-
List chord types for a given root note and key.
Parameters:
- note_num integer MIDI note number (0-127) for root of chord.
- key_root integer MIDI note number (0-127) for root of key.
- key_type string String defining key type (eg, "major", "aeolian" or "neapolitan major"), see class for full list.
Returns:
-
{string...}
Array of chord type strings that fit the criteria.
- snap_note_to_array (note_num, snap_array)
-
Snap a MIDI note number to the nearest note number in an array.
Parameters:
- note_num integer MIDI note number input (0-127).
- snap_array {integer...} Array of MIDI note numbers to snap to, must be in low to high order.
Returns:
-
integer
Adjusted note number.
- snap_notes_to_array (note_nums_array, snap_array)
-
Snap an array of MIDI note numbers to an array of note numbers.
Parameters:
- note_nums_array {integer...} Array of input MIDI note numbers.
- snap_array {integer...} Array of MIDI note numbers to snap to, must be in low to high order.
Returns:
-
{integer...}
Array of adjusted note numbers.
- note_num_to_name (note_num[, include_octave])
-
Return a MIDI note number's note name.
Parameters:
- note_num integer MIDI note number (0-127).
- include_octave boolean Include octave number in return string if set to true. (optional)
Returns:
-
string
Name string (eg, "C#3").
- note_nums_to_names (note_nums_array[, include_octave])
-
Return an array of MIDI note numbers' names.
Parameters:
- note_nums_array {integer...} Array of MIDI note numbers.
- include_octave boolean Include octave number in return strings if set to true. (optional)
Returns:
-
{string...}
Array of name strings.
- note_num_to_freq (note_num)
-
Return a MIDI note number's frequency.
Parameters:
- note_num integer MIDI note number (0-127).
Returns:
-
float
Frequency number in Hz.
- note_nums_to_freqs (note_nums_array)
-
Return an array of MIDI note numbers' frequencies.
Parameters:
- note_nums_array {integer...} Array of MIDI note numbers.
Returns:
-
{float...}
Array of frequency numbers in Hz.
- freq_to_note_num (freq)
-
Return a frequency's nearest MIDI note number.
Parameters:
- freq float Frequency number in Hz.
Returns:
-
integer
MIDI note number (0-127).
- freqs_to_note_nums (freqs_array)
-
Return an array of frequencies' nearest MIDI note numbers.
Parameters:
- freqs_array {float...} Array of frequency numbers in Hz.
Returns:
-
{integer...}
Array of MIDI note numbers.
- interval_to_ratio (interval)
-
Return the ratio of an interval.
Parameters:
- interval float Interval in semitones.
Returns:
-
float
Ratio number.
- intervals_to_ratios (intervals_array)
-
Return an array of ratios of intervals.
Parameters:
- intervals_array {float...} Array of intervals in semitones.
Returns:
-
{float...}
Array of ratio numbers.
- ratio_to_interval (ratio)
-
Return the interval of a ratio.
Parameters:
- ratio float Ratio number.
Returns:
-
float
Interval in semitones.
- ratios_to_intervals (ratios_array)
-
Return an array of intervals of ratios.
Parameters:
- ratios_array {float...} Array of ratio numbers.
Returns:
-
{float...}
Array of intervals in semitones.