Enum LPR 

pub enum LPR {
    Leading,
    Parallel,
    Relative,
}

Enumerates primary available transformations in Neo-Riemannian theory.

Each transformation is invertible, meaning that consecutive applications of any transformation will return the original triad. Furthermore, LPR transformations may be chained together in discrete or continuous sequences to create complex harmonic progressions.

The transformations are:

• Leading (L):
  • [Major] given a major triad, subtract a semitone from the root and move it to the fifth
  • [Minor] given a minor triad, add a semitone to the fifth and move it to the root
• Parallel (P):
  • [Major] given a major triad, subtract a semitone from the third
  • [Minor] given a minor triad, add a semitone to the third
• Relative (R):
  • [Major] given a major triad, add a tone to the fifth and move it to the root
  • [Minor] given a minor triad, subtract a tone from the root and move it to the fifth

These transformations can be described categorically as morphisms between various triads. More specifically, they are contravariant functors between categories of triads.

Variants

Leading

Leading (L) transformation

Parallel

Parallel (P) transformation

Relative

Relative (R) transformation

Implementations

impl LPR

pub const fn is_leading(&self) -> bool

Returns true if the enum is LPR::Leading otherwise false

pub const fn is_parallel(&self) -> bool

Returns true if the enum is LPR::Parallel otherwise false

pub const fn is_relative(&self) -> bool

Returns true if the enum is LPR::Relative otherwise false

impl LPR

pub fn leading() -> Self

pub fn parallel() -> Self

pub fn relative() -> Self

pub fn apply(&self, triad: &Triad) -> Triad

pub fn try_apply(&self, triad: &Triad) -> Result<Triad, MusicError>

Apply a transformation to a triad

Trait Implementations

impl AsRef<str> for LPR

fn as_ref(&self) -> &str

Converts this type into a shared reference of the (usually inferred) input type.

impl Clone for LPR

fn clone(&self) -> LPR

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for LPR

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for LPR

fn default() -> LPR

Returns the “default value” for a type.

impl Display for LPR

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl EnumCount for LPR

const COUNT: usize = 3usize

impl From<LPR> for usize

fn from(value: LPR) -> Self

Converts to this type from the input type.

impl From<char> for LPR

fn from(value: char) -> Self

Converts to this type from the input type.

impl From<usize> for LPR

fn from(value: usize) -> Self

Converts to this type from the input type.

impl FromStr for LPR

type Err = ParseError

The associated error which can be returned from parsing.

fn from_str(s: &str) -> Result<LPR, <Self as FromStr>::Err>

Parses a string s to return a value of this type.

impl Hash for LPR

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl IntoEnumIterator for LPR

type Iterator = LPRIter

fn iter() -> LPRIter

impl Mul<LPR> for Triad

type Output = Triad

The resulting type after applying the * operator.

fn mul(self, rhs: LPR) -> Self::Output

Performs the * operation.

impl MulAssign<LPR> for Triad

fn mul_assign(&mut self, rhs: LPR)

Performs the *= operation.

impl Ord for LPR

fn cmp(&self, other: &LPR) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for LPR

fn eq(&self, other: &LPR) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for LPR

fn partial_cmp(&self, other: &LPR) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl TryFrom<&str> for LPR

type Error = ParseError

The type returned in the event of a conversion error.

fn try_from(s: &str) -> Result<LPR, <Self as TryFrom<&str>>::Error>

Performs the conversion.

impl VariantArray for LPR

const VARIANTS: &'static [Self]

impl VariantNames for LPR

const VARIANTS: &'static [&'static str]

Names of the variants of this enum

impl Copy for LPR

impl Eq for LPR

impl StructuralPartialEq for LPR