Expand description
Decimal
Decimal allows storing real number to arbitrary precision; which
avoids common floating point errors (such as 0.1 + 0.2 ≠ 0.3) at the
cost of complexity.
Internally, Decimal uses a 256-bit integer, paired with a 64-bit
integer which determines the position of the decimal point. Therefore,
the precision is not actually arbitrary, but limited to 263
decimal places.
Common numerical operations are overloaded, so we can treat them the same way we treat other numbers.
It is not recommended to convert a floating point number to a decimal directly, as the floating point representation may be unexpected.
§Example
use fdecimal::Decimal;
use std::str::FromStr;
let input = "0.8";
let dec = Decimal::from_str(&input).unwrap();
let float = f32::from_str(&input).unwrap();
println!("Input ({}) with decimals: {} vs {})", input, dec, float);