Percentage Type with Decimal

A type to represent percentage with high precision thanks to rust_decimal.

A percentage can perform addition, subtraction and multiplication.

use decimal_percentage::Percentage;
use rust_decimal::Decimal;

let p1 = Percentage::from(0.1f64);
let p2 = Percentage::from(0.1f32);
let p3 = Percentage::try_from("0.1").unwrap();
let p4 = Percentage::from(Decimal::from_f64(0.3).unwrap());

assert_eq!(p1 + p2, Percentage::from(0.2));
assert_eq!(p1 + 0.2, Percentage::from(0.3));
assert_eq!(p4 - p2, Percentage::from(0.2));
assert_eq!(p1 * 66.0, 6.6);
assert_eq!(p1 * 100u32, 10u32);
assert_eq!(p1 * -100i32, -10i32);
// note that a multiplication to integer type can lose precision
assert_eq!(p1 * -33i32, -3i32);
// multiplication on extremely small value with Decimal,
// that is not representable with float point
let small_value = Decimal::from_str("0.0000000000000000002").unwrap();
assert_eq!(p1 * small_value, Decimal::from_str("0.00000000000000000002").unwrap());

Contributing

Contributions and feed back are welcome following Github workflow.

License

decimal_percentage is provided under the MIT license. See LICENSE.