Arbitrary-precision numbers

The rug crate provides integers and floating-point numbers with arbitrary precision and correct rounding. Its main features are:

• big integers with arbitrary precision,
• big rational numbers with arbitrary precision,
• multi-precision floating-point numbers with correct rounding, and
• multi-precision complex numbers with correct rounding.

This crate is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. See the full text of the GNU LGPL and GNU GPL for details.

Basic use

Documentation for this crate is available. This crate depends on the low-level bindings in the gmp-mpfr-sys crate, which provides RUST FFI bindings for:

• the GNU Multiple Precision Arithmetic Library (GMP),
• the GNU MPFR Library, a library for multiple-precision floating-point computations, and
• GNU MPC, a library for the arithmetic of complex numbers with arbitrarily high precision.

It can be helpful to refer to the documentation of the GMP, MPFR and MPC libraries.

Examples

extern crate rug;
use rug::{Assign, Integer};

fn main() {
    // Create an integer initialized as zero.
    let mut int = Integer::new();
    assert_eq!(int, 0);
    int.assign(14);
    assert_eq!(int, 14);
    let hex_160 = "ffff0000ffff0000ffff0000ffff0000ffff0000";
    int.assign_str_radix(hex_160, 16).unwrap();
    assert_eq!(int.significant_bits(), 160);
    int = (int >> 128) - 1;
    assert_eq!(int, 0xfffe_ffff_u32);
}

Usage

To use rug in your crate, add extern crate rug; to the crate root and add rug as a dependency in Cargo.toml:

[dependencies]
rug = "0.6.0"

The rug crate depends on the low-level bindings in the gmp-mpfr-sys crate. This should be transparent on GNU/Linux and macOS, but may need some work on Windows. See the gmp-mpfr-sys documentation for some details.

Optional features

The rug crate has five optional features: integer, rational, float, complex and rand. The traits in the ops module are always included. The optional features are enabled by default; to disable them add this to Cargo.toml:

[dependencies.rug]
version = "0.6.0"
default-features = false

If no optional features are selected, the gmp-mpfr-sys crate is not required and thus not enabled.

To use features selectively, you can add this to Cargo.toml:

[dependencies.rug]
version = "0.6.0"
default-features = false
# Pick which features to use
features = ["integer", "float", "rand"]

Note that both the rational feature and the rand feature depend on, and will enable, the integer feature. Similarly the complex feature depends on, and will enable, the float feature.