Trait rug::ops::AddFromRound
source · [−]pub trait AddFromRound<Lhs = Self> {
type Round;
type Ordering;
fn add_from_round(&mut self, lhs: Lhs, round: Self::Round) -> Self::Ordering;
}Expand description
Compound addition and assignment to the rhs operand with a specified rounding method.
Examples
use core::cmp::Ordering;
use rug::{
float::Round,
ops::{AddAssignRound, AddFromRound},
Float,
};
struct F(f64);
impl AddFromRound<f64> for F {
type Round = Round;
type Ordering = Ordering;
fn add_from_round(&mut self, lhs: f64, round: Round) -> Ordering {
let mut f = Float::with_val(53, lhs);
let dir = f.add_assign_round(self.0, round);
self.0 = f.to_f64();
dir
}
}
let mut f = F(5.0);
let dir = f.add_from_round(3.0, Round::Nearest);
// 3.0 + 5.0 = 8.0
assert_eq!(f.0, 8.0);
assert_eq!(dir, Ordering::Equal);Associated Types
Required methods
fn add_from_round(&mut self, lhs: Lhs, round: Self::Round) -> Self::Ordering
fn add_from_round(&mut self, lhs: Lhs, round: Self::Round) -> Self::Ordering
Performs the addition.
Examples
use core::cmp::Ordering;
use rug::{float::Round, ops::AddFromRound, Float};
// only four significant bits
let mut f = Float::with_val(4, -0.3);
let dir = f.add_from_round(-3, Round::Nearest);
// −3.3 rounded up to −3.25
assert_eq!(f, -3.25);
assert_eq!(dir, Ordering::Greater);