#port #bignum #math

no-std omeganum

Stores numbers up to 10{N}9e15

2 stable releases

1.0.1 Oct 15, 2024

#78 in No standard library

MIT license

51KB
1.5K SLoC

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OmegaNum.rs

This is a direct port of Naruyoko's OmegaNum.js to Rust.

Using this library, you are able to store numbers up to 10{N}9e15 in Bower's operator notation, with no hard limit on N. Note that some functions (for example, the gamma function) are left unimplemented. I may add them in later.

This crate supports #![no-std].

Features

  • default: Enables std
  • std: Enables using the standard library
  • error_in_core: Enables implementing the recently stabilized[^1] core::error::Error on error types when std is not enabled
  • libm: Required without std enabled for math
  • serde: Enables support for serde::Serialize and serde::Deserialize
  • f16: Enables support for converting from the experimental f16 type

An f128 feature is planned for when that type gains the necessary method log10.

[^1]: in Rust version 1.81.0

Usage

use omeganum::{OmegaNum, constant};
use std::borrow::Cow;

// Create constants like this:
const ONE: OmegaNum = constant!(1);
// or like this:
const TEN_E_TWENTY: OmegaNum = OmegaNum::from_parts(
    // The base and array are stored separately,
    // which makes numerous operations much faster by avoiding
    // accessing the heap
    1.0, Cow::Borrowed(&[20.0])
);

// Numbers will coerce to OmegaNum when operated with them
assert_eq!(ONE + 1, 2); 
// ONE + OmegaNum::from(1) == OmegaNum::from(2)

// Math operations move the value, requiring explicitly defined cloning
let seventeen = OmegaNum::from(17);
let log10_17 = seventeen.log10();
// The below code doesn't work, as log10 consumed seventeen
// println!("log10 {seventeen} is {log10_seventeen}");

// Instead, do this:
let seventeen = OmegaNum::from(17);
let log10_17 = seventeen.clone().log10();
println!("log10 {seventeen} is {log10_17}");

// Constants store their arrays statically:
let c = constant!(7);
assert!(matches!(c.into_parts().1, Cow::Borrowed(_)));

Licensing

This project is under the MIT license, which can be found at the root of the repository under LICENSE. Additionally, the license of OmegaNum.js, the work this is derived from, can be found at LICENSE-OMEGANUM - it is also licensed under the MIT license.

Dependencies

~93–405KB