https://github.com/purescript-contrib/purescript-rationals

Rational numbers for PureScript
https://github.com/purescript-contrib/purescript-rationals

purescript

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Rational numbers for PureScript

• Host: GitHub
• URL: https://github.com/purescript-contrib/purescript-rationals
• Owner: purescript-contrib
• License: mit
• Created: 2015-08-12T10:53:12.000Z (over 9 years ago)
• Default Branch: master
• Last Pushed: 2024-06-27T18:27:01.000Z (5 months ago)
• Last Synced: 2024-11-11T12:26:49.432Z (3 days ago)
• Topics: purescript
• Language: PureScript
• Size: 64.5 KB
• Stars: 13
• Watchers: 5
• Forks: 13
• Open Issues: 2
• Metadata Files:
  • Readme: README.md
  • Changelog: CHANGELOG.md
  • Contributing: CONTRIBUTING.md
  • License: LICENSE

Awesome Lists containing this project

• awesome-purescript - rationals - Rational numbers. (Maths)

README

        
# Rationals

[![CI](https://github.com/purescript-contrib/purescript-rationals/workflows/CI/badge.svg?branch=master)](https://github.com/purescript-contrib/purescript-rationals/actions?query=workflow%3ACI+branch%3Amaster)

[![Release](https://img.shields.io/github/release/purescript-contrib/purescript-rationals.svg)](https://github.com/purescript-contrib/purescript-rationals/releases)

[![Pursuit](https://pursuit.purescript.org/packages/purescript-rationals/badge)](https://pursuit.purescript.org/packages/purescript-rationals)

[![Maintainer: gbagan](https://img.shields.io/badge/maintainer-gbagan-teal.svg)](https://github.com/gbagan)

Using numbers to do arithmetic with fractions in PureScript may yield surprising results:

```

> 0.1 + 0.2

0.30000000000000004

```

The same can be expressed accurately with `Rational` using the `(%)` operator:

```

> import Data.Rational

> (1 % 10) + (2 % 10)

3 % 10

```

You can turn a `Rational` to a `Number`:

```

> toNumber (3 % 10)

0.3

```

## Installation

Install `rationals` with [Spago](https://github.com/purescript/spago):

```sh

spago install rationals

# Or with Bower

bower install purescript-rationals

```

## Other Ratios

`Rational` is just a newtype over `Ratio BigInt` and you might want to use

`Ratio` with other than `BigInt`. The type you choose must however be an `EuclideanRing`.

```

> import Data.Ratio ((%), reduce)

> import Data.BigInt (fromInt, fromString)

> :type fromInt 1 % fromInt 3

Ratio BigInt

> reduce <$> fromString "10" <*> fromString "857981209301293808359384092830482"

(Just fromString "5" % fromString "428990604650646904179692046415241")

```

## Documentation

`rationals` documentation is stored in a few places:

1. Module documentation is [published on Pursuit](https://pursuit.purescript.org/packages/purescript-rationals).

2. Usage examples can be found in [the test suite](./test).

If you get stuck, there are several ways to get help:

- [Open an issue](https://github.com/purescript-contrib/purescript-rationals/issues) if you have encountered a bug or problem.

- Ask general questions on the [PureScript Discourse](https://discourse.purescript.org) forum or the [PureScript Discord](https://discord.com/invite/sMqwYUbvz6) chat.

## Contributing

You can contribute to `rationals` in several ways:

1. If you encounter a problem or have a question, please [open an issue](https://github.com/purescript-contrib/purescript-rationals/issues). We'll do our best to work with you to resolve or answer it.

2. If you would like to contribute code, tests, or documentation, please [read the contributor guide](./CONTRIBUTING.md). It's a short, helpful introduction to contributing to this library, including development instructions.

3. If you have written a library, tutorial, guide, or other resource based on this package, please share it on the [PureScript Discourse](https://discourse.purescript.org)! Writing libraries and learning resources are a great way to help this library succeed.