NAME

Music::Intervals - Breakdown of musical intervals

VERSION

version 0.0702

SYNOPSIS

use Music::Intervals;

my $m = Music::Intervals->new(
  notes => [qw/C E G B/],
  size  => 3, # Must be <= the notes
);

# Then any of:
print Dumper(
  $m->chord_names,
  $m->natural_frequencies,
  $m->natural_intervals,
  $m->natural_cents,
  $m->natural_prime_factors,
  $m->eq_tempered_frequencies,
  $m->eq_tempered_intervals,
  $m->eq_tempered_cents,
  $m->integer_notation,
);

# Find known intervals
$name  = $m->by_ratio($ratio);
$ratio = $m->by_name($interval_name);

perl -Ilib -MMusic::Intervals::Ratios -E'say $Music::Intervals::Ratios::ratio->{C}{name}'
# unison, perfect prime, tonic

# Show all the 447 known intervals:
perl -MData::Dumper -MMusic::Intervals::Ratios -e'print Dumper $Music::Intervals::Ratios::ratio'

DESCRIPTION

A Music::Intervals object shows the breakdown of musical notes, intervals and chords.

This module reveals the "guts" within a given tonality. And by guts I mean, the measurements of the notes and the intervals between them.

For Western notes and intervals, this tonality begins with the C note. That is, all intervals are calculated from C. So, if you want to analyze a minor chord, either make it start on C (like [C Eb G]) or somewhere between C and B (like [D F A]).

ATTRIBUTES

rootless

Show chord names with no root.

Default: 0

octave

The octave to use in internal computations.

Default: 4

concert

Concert pitch to use in internal computations.

Default: 440

size

Chord size

Default: 3

tonic

The root of the computations.

Default: C

* Currently (and for the foreseeable future) this will remain the only value that produces sane results.

semitones

Number of notes in the scale, used in internal computations.

Default: 12

temper

Physical distance between notes, used in internal computations.

Default: semitones * 100 / log(2)

notes

The actual notes to use in the computation.

Default: [ C D E F G A B ]

The list of notes may be any of the keys in the Music::Intervals::Ratios ratio hashref. This is very very long and contains useful intervals such as those of the common scale and even the Pythagorean intervals, too.

A few examples:

[qw( C E G )]
[qw( C D D# )]
[qw( C D Eb )]
[qw( C D D# Eb E E# Fb F )]
[qw( C 11h 7h )]
[qw( C pM3 pM7 )]

For natural_intervals this last example produces the following:

'C pM3 pM7' => {
  'C pM3' => { '81/64' => 'Pythagorean major third' },
  'C pM7' => { '243/128' => 'Pythagorean major seventh' },
  'pM3 pM7' => { '3/2' => 'perfect fifth' }
}

Note that case matters for interval names. For example, "M" means major and "m" means minor.

midikey

Default: 69

scale

Describe this...

METHODS

new

$x = Music::Intervals->new(%arguments);

Create a new Music::Intervals object.

chord_names

integer_notation

eq_tempered_cents

eq_tempered_frequencies

eq_tempered_intervals

natural_cents

natural_frequencies

natural_intervals

natural_prime_factors

dyads

Return pairs of the given notes with fractional and pitch ratio parts.

ratio_factorize

Return the dyadic fraction as a prime factored expression.

by_name

$ratio = $m->by_name('C');
# { ratio => '1/1', name => 'unison, perfect prime, tonic' }

Return a known ratio or undef.

by_ratio

$name = $m->by_ratio('1/1');
# { 'symbol' => 'C', 'name' => 'unison, perfect prime, tonic' }

Return a known ratio name or undef.

SEE ALSO

The t/ tests and eg/ example in this distribution

For the time being, you will need to look at the source of Music::Intervals::Ratios for the note and interval names.

Music::Intervals::Numeric for numeric-only note-intervals

http://en.wikipedia.org/wiki/List_of_musical_intervals

http://en.wikipedia.org/wiki/Equal_temperament

http://en.wikipedia.org/wiki/Just_intonation

Music::Scala - A powerful module encompassing thousands of scales and the ratios therein

AUTHOR

Gene Boggs <gene@cpan.org>

COPYRIGHT AND LICENSE

This software is copyright (c) 2022 by Gene Boggs.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.