round.rs - source
Description: Source of the Rust file `src/round.rs`.
Keywords: rust, rustlang, rust-lang

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    use super::*;

    /// Trait for rounding values to a number of decimal places
    pub trait Round {
        /// Rounds the value to a number of decimal places
        fn round_to(self, places: i32) -> Self;
    }

    // Round an f32 to a number of decimal places
    fn round_to(val: f32, places: i32) -> f32 {
        let mult = 10_f32.powi(places);
        (val * mult).round() / mult
    }

    impl Round for DeltaE {
        fn round_to(self, places: i32) -> Self {
            Self {
                value: round_to(self.value, places),
                ..self
            }
        }
    }

    impl Round for LabValue {
        fn round_to(self, places: i32) -> LabValue {
            Self {
                l: round_to(self.l, places),
                a: round_to(self.a, places),
                b: round_to(self.b, places),
            }
        }
    }

    impl Round for LchValue {
        fn round_to(self, places: i32) -> LchValue {
            Self {
                l: round_to(self.l, places),
                c: round_to(self.c, places),
                h: round_to(self.h, places),
            }
        }
    }

    impl Round for XyzValue {
        fn round_to(self, places: i32) -> XyzValue {
            Self {
                x: round_to(self.x, places),
                y: round_to(self.y, places),
                z: round_to(self.z, places),
            }
        }
    }

    #[test]
    fn round() {
        let val = 1.234567890;
        let rnd = round::round_to(val, 4);
        assert_eq!(rnd, 1.2346);
        assert_ne!(rnd, val);
    }