Trait surge_wavetable::imports::Mul1.0.0[−][src]

pub trait Mul<Rhs = Self> {
    type Output;
    fn mul(self, rhs: Rhs) -> Self::Output;
}
Expand description

The multiplication operator *.

Note that Rhs is Self by default, but this is not mandatory.

Examples

Multipliable rational numbers

use std::ops::Mul;

// By the fundamental theorem of arithmetic, rational numbers in lowest
// terms are unique. So, by keeping `Rational`s in reduced form, we can
// derive `Eq` and `PartialEq`.
#[derive(Debug, Eq, PartialEq)]
struct Rational {
    numerator: usize,
    denominator: usize,
}

impl Rational {
    fn new(numerator: usize, denominator: usize) -> Self {
        if denominator == 0 {
            panic!("Zero is an invalid denominator!");
        }

        // Reduce to lowest terms by dividing by the greatest common
        // divisor.
        let gcd = gcd(numerator, denominator);
        Self {
            numerator: numerator / gcd,
            denominator: denominator / gcd,
        }
    }
}

impl Mul for Rational {
    // The multiplication of rational numbers is a closed operation.
    type Output = Self;

    fn mul(self, rhs: Self) -> Self {
        let numerator = self.numerator * rhs.numerator;
        let denominator = self.denominator * rhs.denominator;
        Self::new(numerator, denominator)
    }
}

// Euclid's two-thousand-year-old algorithm for finding the greatest common
// divisor.
fn gcd(x: usize, y: usize) -> usize {
    let mut x = x;
    let mut y = y;
    while y != 0 {
        let t = y;
        y = x % y;
        x = t;
    }
    x
}

assert_eq!(Rational::new(1, 2), Rational::new(2, 4));
assert_eq!(Rational::new(2, 3) * Rational::new(3, 4),
           Rational::new(1, 2));

Multiplying vectors by scalars as in linear algebra

use std::ops::Mul;

struct Scalar { value: usize }

#[derive(Debug, PartialEq)]
struct Vector { value: Vec<usize> }

impl Mul<Scalar> for Vector {
    type Output = Self;

    fn mul(self, rhs: Scalar) -> Self::Output {
        Self { value: self.value.iter().map(|v| v * rhs.value).collect() }
    }
}

let vector = Vector { value: vec![2, 4, 6] };
let scalar = Scalar { value: 3 };
assert_eq!(vector * scalar, Vector { value: vec![6, 12, 18] });

Associated Types

The resulting type after applying the * operator.

Required methods

Performs the * operation.

Example
assert_eq!(12 * 2, 24);

Implementations on Foreign Types

Implementors

Perform elementwise multiplication between references self and rhs, and return the result as a new Array.

If their shapes disagree, self and rhs is broadcast to their broadcast shape, cloning the data if needed.

Panics if broadcasting isn’t possible.

Perform elementwise multiplication between self and reference rhs, and return the result.

rhs must be an Array or ArcArray.

If their shapes disagree, self is broadcast to their broadcast shape, cloning the data if needed.

Panics if broadcasting isn’t possible.

Perform elementwise multiplication between reference self and rhs, and return the result.

rhs must be an Array or ArcArray.

If their shapes disagree, self is broadcast to their broadcast shape, cloning the data if needed.

Panics if broadcasting isn’t possible.

Perform elementwise multiplication between the reference self and the scalar x, and return the result as a new Array.

Perform elementwise multiplication between self and rhs, and return the result.

self must be an Array or ArcArray.

If their shapes disagree, self is broadcast to their broadcast shape.

Panics if broadcasting isn’t possible.

Perform elementwise multiplication between self and the scalar x, and return the result (based on self).

self must be an Array or ArcArray.