# Fixed-point numbers The [*fixed* crate] provides fixed-point numbers. Currently it uses the [*typenum* crate] for the fractional bit count; it is planned to move to [const generics] when they are implemented by the Rust compiler. The crate provides the following types: * [`FixedI8`] is a signed eight-bit fixed-point number, * [`FixedI16`] is a signed 16-bit fixed-point number, * [`FixedI32`] is a signed 32-bit fixed-point number, * [`FixedI64`] is a signed 64-bit fixed-point number, * [`FixedI128`] is a signed 128-bit fixed-point number, * [`FixedU8`] is an unsigned eight-bit fixed-point number, * [`FixedU16`] is an unsigned 16-bit fixed-point number, * [`FixedU32`] is an unsigned 32-bit fixed-point number, * [`FixedU64`] is an unsigned 64-bit fixed-point number, and * [`FixedU128`] is an unsigned 128-bit fixed-point number. All fixed-point numbers can have `Frac` fractional bits, where `Frac` can have any value from 0 up to and including the size of the number in bits. When `Frac` is 0, the fixed-point number behaves like an integer. When `Frac` is equal to the number of bits, the value of the fixed-point number lies in the range −0.5 ≤ *x* < 0.5 for signed fixed-point numbers, and in the range 0 ≤ *x* < 1 for unsigned fixed-point numbers. ## What’s new ### Version 0.1.1 news (unreleased) * New static methods [`int_bits`] and [`frac_bits`] were added. * Support for multiplication and division by integers was added. [`frac_bits`]: https://docs.rs/fixed/0.1.0/fixed/struct.FixedI32.html#method.frac_bits [`int_bits`]: https://docs.rs/fixed/0.1.0/fixed/struct.FixedI32.html#method.int_bits ### Version 0.1.0 news (2018-08-10) * [`Unsigned`] constants provided by the [*typenum* crate] are now used for the number of fractional bits. * Many methods and trait implementations available for primitive integers are now also supported by the fixed-point numbers. [`Unsigned`]: https://docs.rs/typenum/^1.3/typenum/marker_traits/trait.Unsigned.html ### Other releases Details on other releases can be found in [*RELEASES.md*]. [*RELEASES.md*]: https://gitlab.com/tspiteri/fixed/blob/master/RELEASES.md ## Using the *fixed* crate The *fixed* crate is available on [crates.io][*fixed* crate]. To use it in your crate, add it as a dependency inside [*Cargo.toml*]: ```toml [dependencies] fixed = "0.1.0" ``` You also need to declare it by adding this to your crate root (usually *lib.rs* or *main.rs*): ```rust extern crate fixed; ``` ## License This crate is free software: you can redistribute it and/or modify it under the terms of either * the [Apache License, Version 2.0][LICENSE-APACHE] or * the [MIT License][LICENSE-MIT] at your option. ### Contribution Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache License, Version 2.0, shall be dual licensed as above, without any additional terms or conditions. [*Cargo.toml*]: https://doc.rust-lang.org/cargo/guide/dependencies.html [*fixed* crate]: https://crates.io/crates/fixed [*typenum* crate]: https://crates.io/crates/typenum [LICENSE-APACHE]: https://www.apache.org/licenses/LICENSE-2.0 [LICENSE-MIT]: https://opensource.org/licenses/MIT [`FixedI128`]: https://docs.rs/fixed/0.1.0/fixed/struct.FixedI128.html [`FixedI16`]: https://docs.rs/fixed/0.1.0/fixed/struct.FixedI16.html [`FixedI32`]: https://docs.rs/fixed/0.1.0/fixed/struct.FixedI32.html [`FixedI64`]: https://docs.rs/fixed/0.1.0/fixed/struct.FixedI64.html [`FixedI8`]: https://docs.rs/fixed/0.1.0/fixed/struct.FixedI8.html [`FixedU128`]: https://docs.rs/fixed/0.1.0/fixed/struct.FixedU128.html [`FixedU16`]: https://docs.rs/fixed/0.1.0/fixed/struct.FixedU16.html [`FixedU32`]: https://docs.rs/fixed/0.1.0/fixed/struct.FixedU32.html [`FixedU64`]: https://docs.rs/fixed/0.1.0/fixed/struct.FixedU64.html [`FixedU8`]: https://docs.rs/fixed/0.1.0/fixed/struct.FixedU8.html [channels]: https://doc.rust-lang.org/book/second-edition/appendix-07-nightly-rust.html [const generics]: https://github.com/rust-lang/rust/issues/44580