Enum rug::float::Round

source ·
pub enum Round {
    Nearest,
    Zero,
    Up,
    Down,
    // some variants omitted
}
Expand description

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;
use rug::ops::AssignRound;
use rug::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;
use rug::ops::AssignRound;
use rug::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

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

Returns a copy of the value. Read more
Performs copy-assignment from source. Read more
Formats the value using the given formatter. Read more
Returns the “default value” for a type. Read more
Feeds this value into the given Hasher. Read more
Feeds a slice of this type into the given Hasher. Read more
This method returns an Ordering between self and other. Read more
Compares and returns the maximum of two values. Read more
Compares and returns the minimum of two values. Read more
Restrict a value to a certain interval. Read more
This method tests for self and other values to be equal, and is used by ==. Read more
This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason. Read more
This method returns an ordering between self and other values if one exists. Read more
This method tests less than (for self and other) and is used by the < operator. Read more
This method tests less than or equal to (for self and other) and is used by the <= operator. Read more
This method tests greater than (for self and other) and is used by the > operator. Read more
This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more
Casts the value.
Immutably borrows from an owned value. Read more
Mutably borrows from an owned value. Read more
Casts the value.
Casts the value.
Casts the value.

Returns the argument unchanged.

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

Casts the value.
Casts the value.
Casts the value.
Casts the value.
The resulting type after obtaining ownership.
Creates owned data from borrowed data, usually by cloning. Read more
Uses borrowed data to replace owned data, usually by cloning. Read more
The type returned in the event of a conversion error.
Performs the conversion.
The type returned in the event of a conversion error.
Performs the conversion.
Casts the value.
Casts the value.
Casts the value.
Casts the value.