Trait num_traits::ops::euclid::Euclid
source · pub trait Euclid: Sized + Div<Self, Output = Self> + Rem<Self, Output = Self> {
// Required methods
fn div_euclid(&self, v: &Self) -> Self;
fn rem_euclid(&self, v: &Self) -> Self;
}
Required Methods§
sourcefn div_euclid(&self, v: &Self) -> Self
fn div_euclid(&self, v: &Self) -> Self
Calculates Euclidean division, the matching method for rem_euclid
.
This computes the integer n
such that
self = n * v + self.rem_euclid(v)
.
In other words, the result is self / v
rounded to the integer n
such that self >= n * v
.
Examples
use num_traits::Euclid;
let a: i32 = 7;
let b: i32 = 4;
assert_eq!(Euclid::div_euclid(&a, &b), 1); // 7 > 4 * 1
assert_eq!(Euclid::div_euclid(&-a, &b), -2); // -7 >= 4 * -2
assert_eq!(Euclid::div_euclid(&a, &-b), -1); // 7 >= -4 * -1
assert_eq!(Euclid::div_euclid(&-a, &-b), 2); // -7 >= -4 * 2
sourcefn rem_euclid(&self, v: &Self) -> Self
fn rem_euclid(&self, v: &Self) -> Self
Calculates the least nonnegative remainder of self (mod v)
.
In particular, the return value r
satisfies 0.0 <= r < v.abs()
in
most cases. However, due to a floating point round-off error it can
result in r == v.abs()
, violating the mathematical definition, if
self
is much smaller than v.abs()
in magnitude and self < 0.0
.
This result is not an element of the function’s codomain, but it is the
closest floating point number in the real numbers and thus fulfills the
property self == self.div_euclid(v) * v + self.rem_euclid(v)
approximatively.
Examples
use num_traits::Euclid;
let a: i32 = 7;
let b: i32 = 4;
assert_eq!(Euclid::rem_euclid(&a, &b), 3);
assert_eq!(Euclid::rem_euclid(&-a, &b), 1);
assert_eq!(Euclid::rem_euclid(&a, &-b), 3);
assert_eq!(Euclid::rem_euclid(&-a, &-b), 1);