# Crate fixed[−][src]

# 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.

## Quick example

use fixed::frac; use fixed::FixedI32; // 20 integer bits, 12 fractional bits type I20F12 = FixedI32<frac::U12>; // 19/3 = 6 1/3 let six_and_third = I20F12::from_int(19).unwrap() / 3; // four decimal digits for 12 binary digits assert_eq!(six_and_third.to_string(), "6.3333"); // convert to i32, taking the ceil assert_eq!(six_and_third.to_int_ceil(), 7);

## Using the *fixed* crate

The *fixed* crate is available on crates.io. To use
it in your crate, add it as a dependency inside *Cargo.toml*:

```
[dependencies]
fixed = "0.1.1"
```

You also need to declare it by adding this to your crate root (usually
*lib.rs* or *main.rs*):

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 or
- the MIT License

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.

## Modules

frac |
This module reexports items from the |

## Structs

FixedI8 |
An eight-bit fixed-point signed integer
with |

FixedI16 |
A 16-bit fixed-point signed integer
with |

FixedI32 |
A 32-bit fixed-point signed integer
with |

FixedI64 |
A 64-bit fixed-point signed integer
with |

FixedI128 |
A 128-bit fixed-point signed integer
with |

FixedU8 |
An eight-bit fixed-point unsigned integer
with |

FixedU16 |
A 16-bit fixed-point unsigned integer
with |

FixedU32 |
A 32-bit fixed-point unsigned integer
with |

FixedU64 |
A 64-bit fixed-point unsigned integer
with |

FixedU128 |
A 128-bit fixed-point unsigned integer
with |