Enum rug::float::Round

pub enum Round {
    Nearest,
    Zero,
    Up,
    Down,
    // some variants omitted
}

The rounding methods for floating-point values.

When rounding to the nearest, if the number to be rounded is exactly between two representable numbers, it is rounded to the even one, that is, the one with the least significant bit set to zero.

Examples

use rug::{float::Round, ops::AssignRound, Float};
let mut f4 = Float::new(4);
f4.assign_round(10.4, Round::Nearest);
assert_eq!(f4, 10);
f4.assign_round(10.6, Round::Nearest);
assert_eq!(f4, 11);
f4.assign_round(-10.7, Round::Zero);
assert_eq!(f4, -10);
f4.assign_round(10.3, Round::Up);
assert_eq!(f4, 11);

Rounding to the nearest will round numbers exactly between two representable numbers to the even one.

use rug::{float::Round, ops::AssignRound, Float};
// 24 is 11000 in binary
// 25 is 11001 in binary
// 26 is 11010 in binary
// 27 is 11011 in binary
// 28 is 11100 in binary
let mut f4 = Float::new(4);
f4.assign_round(25, Round::Nearest);
assert_eq!(f4, 24);
f4.assign_round(27, Round::Nearest);
assert_eq!(f4, 28);

Variants

Nearest

Round towards the nearest, with ties rounding to even.

Zero

Round towards zero.

Up

Round towards plus infinity.

Down

Round towards minus infinity.

Implementations

impl Round

pub fn reverse(self) -> Round

Reverses the rounding direction.

• Up becomes Down.
• Down becomes Up.
• Other variants are not affected.

Examples

use rug::float::Round;

assert_eq!(Round::Up.reverse(), Round::Down);
assert_eq!(Round::Down.reverse(), Round::Up);
assert_eq!(Round::Nearest.reverse(), Round::Nearest);

Trait Implementations

impl Clone for Round

fn clone(&self) -> Round

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Round

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

Formats the value using the given formatter.

impl Default for Round

fn default() -> Round

Returns the “default value” for a type.

impl Hash for Round

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, 

Feeds a slice of this type into the given Hasher.

impl Ord for Round

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

This method returns an Ordering between self and other.

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

Compares and returns the maximum of two values.

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

Compares and returns the minimum of two values.

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

Restrict a value to a certain interval.

impl PartialEq<Round> for Round

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

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

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

This method tests for !=.

impl PartialOrd<Round> for Round

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

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

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

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

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

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

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

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

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 Copy for Round

impl Eq for Round

impl StructuralEq for Round

impl StructuralPartialEq for Round