Enum magnitude::Magnitude

pub enum Magnitude<T> {
    Finite(T),
    PosInfinite,
    NegInfinite,
}

Represent magnitude of values.

Type Magnitude can be either Finite or infinite(which itself can be PosInfinite or NegInfinite).

This enum is useful when you need to work with algorithms like Dijkstra's Shortest Path or Floyd–Warshall algorithm that require infinite values in order to be written elegantly.

One simple example can be finding the max value in a vector:

use magnitude::Magnitude;

fn find_max(vec: &Vec<Magnitude<i32>>) -> Magnitude<i32> {
    let mut max = Magnitude::NegInfinite;
    for val in vec {
        if *val > max {
            max = *val;
        }
    }

    max
}

let vec: Vec<Magnitude<i32>> = vec![2.into(), 3.into(), 6.into(), (-10).into()];
assert_eq!(find_max(&vec), 6.into());

You can do all valid comparison(==, !=, >, <, >=, <=) and arithmetic(+, -, *, /, +=, -=, *=, /=) operations on magnitudes.
Invalid operations are listed below which means any other operation is valid.

Invalid operations

• Comparison:
  • two PosInfinite
  • two NegInfinite
• Arithmetic:
  • Add:
    • PosInfinite + NegInfinite
  • Sub:
    • PosInfinite - PosInfinite
    • NegInfinite - NegInfinite
  • Mul:
    • zero * PosInfinite
    • zero * NegInfinite
  • Div:
    • non-zero / PosInfinite
    • non-zero / NegInfinite
    • PosInfinite / zero
    • NegInfinite / zero
    • PosInfinite / PosInfinite
    • PosInfinite / NegInfinite
    • NegInfinite / PosInfinite
    • NegInfinite / NegInfinite

Relationship of Magnitude with f64 and f32 infinities

Magnitude as of version 0.2.0 treat f64::INFINITY, f64::NEG_INFINITY, f32::INFINITY, f32::NEG_INFINITY as infinites:

use magnitude::Magnitude;

let pos_inf: Magnitude<f64> = f64::INFINITY.into();
let neg_inf: Magnitude<f64> = f64::NEG_INFINITY.into();
assert!(pos_inf.is_pos_infinite());
assert!(neg_inf.is_neg_infinite());

let pos_inf: Magnitude<f32> = f32::INFINITY.into();
let neg_inf: Magnitude<f32> = f32::NEG_INFINITY.into();
assert!(pos_inf.is_pos_infinite());
assert!(neg_inf.is_neg_infinite());

Examples

Convert a vector of numbers into a vector of magnitudes

use magnitude::Magnitude;

let magnitude_vec = Magnitude::from_vec(&vec![1,2,3]);

assert_eq!(magnitude_vec[0], 1.into());
assert_eq!(magnitude_vec[1], 2.into());
assert_eq!(magnitude_vec[2], 3.into());

Variants

Finite(T)

A finite value

PosInfinite

Positive infinity

NegInfinite

Negative infinity

Implementations

impl<T> Magnitude<T>

pub fn is_pos_infinite(&self) -> bool

Returns true if magnitude is PosInfinite, false otherwise

pub fn is_neg_infinite(&self) -> bool

Returns true if magnitude is NegInfinite, false otherwise

pub fn is_finite(&self) -> bool

Returns true if magnitude is Finite, false otherwise

pub fn as_ref(&self) -> Option<&T>

Returns Some(&T) if magnitude is Finite, None otherwise

pub fn as_ref_mut(&mut self) -> Option<&mut T>

Returns Some(&mut T) if magnitude is Finite, None otherwise

pub fn unwrap(self) -> T

Consumes the Magnitude and returns the value inside Finite. Panics if Magnitude contains an infinity

Example

use magnitude::Magnitude;
let one: Magnitude<i32> = 1.into();

assert_eq!(one.unwrap(), 1);

impl<T: Any + Copy> Magnitude<T>

pub fn from_vec(vec: &Vec<T>) -> Vec<Magnitude<T>>

Converts a vector of value into a vector of Magnitude

Example

use magnitude::Magnitude;

let magnitude_vec = Magnitude::from_vec(&vec![1,2,3]);

assert_eq!(magnitude_vec[0], 1.into());
assert_eq!(magnitude_vec[1], 2.into());
assert_eq!(magnitude_vec[2], 3.into());

Trait Implementations

impl<T: Add<Output = T>> Add<Magnitude<T>> for Magnitude<T>

type Output = Self

The resulting type after applying the + operator.

pub fn add(self, rhs: Self) -> Self::Output

Performs the + operation.

impl<T: Add<Output = T> + Copy> AddAssign<Magnitude<T>> for Magnitude<T>

pub fn add_assign(&mut self, rhs: Self)

Performs the += operation.

impl<T: Clone> Clone for Magnitude<T>

pub fn clone(&self) -> Magnitude<T>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<T: Copy> Copy for Magnitude<T>

impl<T: Debug> Debug for Magnitude<T>

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

Formats the value using the given formatter.

impl<T: Div<Output = T> + PartialOrd + Zero> Div<Magnitude<T>> for Magnitude<T>

type Output = Self

The resulting type after applying the / operator.

pub fn div(self, rhs: Self) -> Self::Output

Performs the / operation.

impl<T: Div<Output = T> + Copy + PartialOrd + Zero> DivAssign<Magnitude<T>> for Magnitude<T>

pub fn div_assign(&mut self, rhs: Self)

Performs the /= operation.

impl<T: PartialEq> Eq for Magnitude<T>

impl<T: Any> From<T> for Magnitude<T>

pub fn from(value: T) -> Self

Performs the conversion.

impl<T: Mul<Output = T> + PartialOrd + Zero> Mul<Magnitude<T>> for Magnitude<T>

type Output = Self

The resulting type after applying the * operator.

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

Performs the * operation.

impl<T: Mul<Output = T> + Copy + PartialOrd + Zero> MulAssign<Magnitude<T>> for Magnitude<T>

pub fn mul_assign(&mut self, rhs: Self)

Performs the *= operation.

impl<T: Neg<Output = T>> Neg for Magnitude<T>

type Output = Self

The resulting type after applying the - operator.

pub fn neg(self) -> Self::Output

Performs the unary - operation.

impl<T: Ord> Ord for Magnitude<T>

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

This method returns an Ordering between self and other.

#[must_use]pub fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

#[must_use]pub fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

#[must_use]pub fn clamp(self, min: Self, max: Self) -> Self

Restrict a value to a certain interval.

impl<T: PartialEq> PartialEq<Magnitude<T>> for Magnitude<T>

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

This method tests for self and other values to be equal, and is used by ==.

#[must_use]pub fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl<T: PartialOrd> PartialOrd<Magnitude<T>> for Magnitude<T>

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

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

#[must_use]pub fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator.

#[must_use]pub fn le(&self, other: &Rhs) -> bool

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

#[must_use]pub fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator.

#[must_use]pub fn ge(&self, other: &Rhs) -> bool

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

impl<T: Sub<Output = T>> Sub<Magnitude<T>> for Magnitude<T>

type Output = Self

The resulting type after applying the - operator.

pub fn sub(self, rhs: Self) -> Self::Output

Performs the - operation.

impl<T: Sub<Output = T> + Copy> SubAssign<Magnitude<T>> for Magnitude<T>

pub fn sub_assign(&mut self, rhs: Self)

Performs the -= operation.