Music

Structures for the creation, analysis, and performance of music in Swift. Check out the documentation.

Overview

Music is a package for anyone who wants to create, analyze, and perform music in pure Swift.

Usage

🎶 Pitch

The Pitch module provides types for structuring and transforming the frequency domain.

Basic Types

let a440: Frequency = 440    // Hz
let middleC: Pitch = 60      // MIDI note number
let e = middleC + 4          // e above middle c
let microtone = e - 0.25     // eighth-tone below the e above middle c
let anyE = Pitch.Class(e)    // pitch class 4
let anyGSharp = anyE.inverse // pitch class 8

Set Operations

let set: Pitch.Class.Collection = [8,0,4,6]
set.normalForm // => [4,6,8,0]
set.primeForm  // => [0,2,4,8]

Row Transformations

let pcs: Pitch.Class.Collection = [0,11,3,4,8,7,9,5,6,1,2,10]
pcs.retrograde // => [10,2,1,6,5,9,7,8,4,3,11,0]
pcs.inversion  // => [0,1,9,8,4,5,3,7,6,11,10,2]

Diatonic Intervals

let majorThird: DiatonicInterval = .M3
let minorSixth = majorThird.inverse
let AAA3 = DiatonicInterval(.triple, .augmented, .third)
let noSuchThing = DiatonicInterval(.major, .fifth) ❌ will not compile!

---

♬ Duration

The Duration module provides types for structuring and transforming the time domain.

Basic Types

let crotchet = Duration(1,4)
let waltz = Meter(3,4)
let stayinAlive = Tempo(100, subdivision: 4)

---

🎚️ Dynamics

The Dynamic module provides ways to describe musical loudness in a highly subjective way.

let loud: Dynamic = .ff
let quiet: Dynamic = .p
let interp = Dynamic.Interpolation(from: .p, to: .ff)

---

🥁 Articulations

The Articulation type provides an interface to describe the way in which a given musical entity is performed.

let short: Articulation = .staccato
let sweet: Articulation = .tenuto
let hard: Articulation = .marcato
let hereIAm: Articulation = .accent

---

💾 MusicModel

The Model brings all of elements together from the modules contained in this package.

let builder = Model.Builder()
let performer = Performer(name: "Pat")
let instrument = Instrument(name: "Euphonium")
let voiceID = builder.createVoice(performer: performer, instrument: instrument)
let pitch: Pitch = 60
let articulation: Articulation = .tenuto
let dynamic: Dynamic = .fff
let note = Rhythm<Event>(1/>1, [event([pitch, dynamic, articulation])])
let rhythmID = builder.createRhythm(note, voiceID: voiceID, offset: .zero)
let model = builder.build()

---

Requirements

In order to use the Music package, you’ll need a few things:

• Swift 5.x Toolchain (Xcode 10.2–11, or here)
• Swift Package Manager

Installation

In order to use the Music modules in your own projects, add it to the dependencies section of your Package.swift file:

let package = Package(
    name: ...,
    products: [ ... ],
    dependencies: [
        ...,
        .package(url: "https://github.com/dn-m/Music", from: "0.17.1")
    ],
    targets: [ ... ]
)

Development

To contribute to the Music package, clone the git repository:

git clone https://github.com/dn-m/Music && cd Music

If you use the Xcode IDE on macOS, you can use SwiftPM to generate an .xcodeproj file:

swift package generate-xcodeproj

Inspiration

Here are some libraries in other languages that have been influential to the design of the Music package:

• Abjad (Python)
• Music21 (Python)
• Haskore (Haskell)
• Mezzo (Haskell)
• GUIDO (C++)