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Music-Intervals-0.0905
River stage one • 1 direct dependent • 2 total dependents
/ Music::Intervals

NAME

Music::Intervals - Breakdown of musical intervals

VERSION

version 0.0905

SYNOPSIS


            

              
              
use Music::Intervals;
my $m = Music::Intervals->new(notes => [qw/C Eb G B/]);
# Then any of:
print Dumper(
  $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
my $name = $m->by_ratio('6/5');
my $ratio = $m->by_name('Eb');
my $intervals = $m->by_description('pythagorean');
perl -MMusic::Intervals::Ratios -E'say $Music::Intervals::Ratios::ratio->{C}{name}'
# unison, perfect prime, tonic
# Show all the 400+ 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 and intervals. (See Music::Intervals::Numeric to use integer ratios instead of named notes.)

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

notes

The actual notes to use in the computation.

Default: [ C E G ]

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' => { '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.

METHODS

new


            

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

Create a new Music::Intervals object.

integer_notation

Math! See source...

eq_tempered_cents

The Equal tempered cents.

eq_tempered_frequencies

The Equal tempered frequencies.

eq_tempered_intervals

The Equal tempered intervals.

natural_cents

Just intonation cents.

natural_frequencies

Just intonation frequencies.

natural_intervals

Just intonation intervals.

natural_prime_factors

Just intonation 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.

by_description


            

              
              
$intervals = $m->by_description('pythagorean');

Search the description of every ratio for the given string.

SEE ALSO

The t/* tests and eg/* examples 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

https://en.wikipedia.org/wiki/Interval_(music)#Main_intervals

https://en.wikipedia.org/wiki/List_of_pitch_intervals

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

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

DEPENDENCIES

Algorithm::Combinatorics

Math::Factor::XS

MIDI::Pitch

Moo

Music::Scales

Number::Fraction

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.