#lang scribble/manual
@(require (for-label racket))

@title{Tuning}
represents a musical tuning@section{related}
 Classes/Scale
@section{categories}
  Tuning

@section{description}

Represents a musical tuning (e.g. equal temperament, just intonation, etc.). Used in conjunction with link::Classes/Scale:: to generate pitch information.


@racketblock[
t = Tuning.et12;
t.semitones;		// [ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 ]
t.ratios;		// [ 1, 1.0594630943591, 1.1224620483089, 1.1892071150019, etc. ]

Pbind(\scale, Scale.major(t), \degree, Pseq((0..7) ++ (6..0) ++ [\rest], 1), \dur, 0.25).play;

// use non-standard tuning
t = Tuning.just;
t.semitones;		// [ 0, 1.1173128526978, 2.0391000173077, 3.1564128700055, etc. ]
t.ratios.collect(_.round(0.001));	// [ 1, 1.067, 1.125, 1.2, 1.25, 1.333, 1.406, 1.5, etc. ]

Pbind(\scale, Scale.major(t), \degree, Pseq((0..7) ++ (6..0) ++ [\rest], 1), \dur, 0.25).play;
::

]
@section{subsection}
 Creation

strong::just, pythagorean, werckmeister, johnston, partch, wcAlpha, bp, etc.::

Creates a tuning from the library stored in 
@racketblock[Tuning.all::. For a complete list of available tunings, execute
]

@racketblock[
Tuning.directory
::

]
@section{CLASSMETHODS}
 

@section{method}
 et
Creates an equal-tempered scale based on pitchesPerOctave.

@section{method}
 choose
Creates a random tuning from the library, constrained by size (which defaults to 12).

@racketblock[
Scale.major(Tuning.choose).tuning.name;
::

]
@section{method}
 new
Creates a Tuning using some or all of the parameters as follows: strong::tuning:: can be the name of a library tuning (in which case that tuning is returned); an array of floats representing the semitone values of the tuning (in which case pitchesPerOctave will be set to the size of the array regardless of the second parameter); or nil (in which case the default tuning for strong::pitchesPerOctave:: will be returned). strong::octaveRatio:: defaults to 2.0, but can be set differently for stretched or compressed tunings.

@racketblock[
Tuning.new(\et12);	// standard equal temperament
// custom tuning
Tuning.new(#[ 0, 0.795, 2.251, 3.251, 4.036, 4.680, 5.915, 7.221, 8.013, 9.29, 9.930, 11.032 ]);
Tuning.new((0..11).collect(_ * (2.08 ** (1/12))), 2.08, "Stretched ET12");
::

]
@section{INSTANCEMETHODS}
 

@section{private}
 storeOn, storedKey, storeArgs, printOn

@section{method}
 semitones
Returns an array of semitone values for the pitch set. link::#-as::(Array) is equivalent; link::#-as::(List) returns it as a list, etc.

@section{method}
 cents
Returns a array of cent values for the pitch set.

@section{method}
 ratios
Returns a tuned array of ratios for the pitch set.

@section{EXAMPLES}
 

For examples of use, see the link::Classes/Scale:: help file.