https://github.com/fkastner/nicenumbers.jl

The nicest numbers in Julia.
https://github.com/fkastner/nicenumbers.jl

julia

Last synced: about 1 year ago
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The nicest numbers in Julia.

• Host: GitHub
• URL: https://github.com/fkastner/nicenumbers.jl
• Owner: fkastner
• License: mit
• Created: 2020-02-23T12:01:14.000Z (over 6 years ago)
• Default Branch: master
• Last Pushed: 2024-04-02T06:21:02.000Z (about 2 years ago)
• Last Synced: 2025-05-07T03:47:14.405Z (about 1 year ago)
• Topics: julia
• Language: Julia
• Homepage: https://fkastner.github.io/NiceNumbers.jl/stable
• Size: 346 KB
• Stars: 27
• Watchers: 1
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

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README

          
# NiceNumbers.jl

*The nicest numbers in Julia*

[![Stable](https://img.shields.io/badge/docs-stable-blue.svg)](https://fkastner.github.io/NiceNumbers.jl/stable)

[![Dev](https://img.shields.io/badge/docs-dev-blue.svg)](https://fkastner.github.io/NiceNumbers.jl/dev)

[![Build Status](https://github.com/fkastner/NiceNumbers.jl/workflows/CI/badge.svg)](https://github.com/fkastner/NiceNumbers.jl/actions)

[![Coverage](https://coveralls.io/repos/github/fkastner/NiceNumbers.jl/badge.svg?branch=master)](https://coveralls.io/github/fkastner/NiceNumbers.jl?branch=master)

This package implements a number type to represent numbers you can safely give to

your students to work with.

The goal is that when common linear algebra or numerical algorithms work using `NiceNumber`s

that then one can be sure that the algorithm can be reasonably easy worked through by hand

with the given numbers.

Nice numbers as implemented in this package consist of a rational part and a square root part with

a rational coefficient. Thus every `NiceNumber` is specified using two `Rational{Int}`s and one `Int`.

## Installation

Just add the package from the Julia Pkg mode:

```julia

julia>] add NiceNumbers

```

## Usage Example

```julia

julia> using NiceNumbers

julia> n = NiceNumber(2,3,5)

Nice number:

   2+3⋅√5

julia> n^2

Nice number:

   49+12⋅√5

julia> m = NiceNumber(3//5)

Nice number:

   3//5

julia> n+m, n-m, n*m, n/m

(13//5+3⋅√5, 7//5+3⋅√5, 6//5+9//5⋅√5, 10//3+5⋅√5)

julia> sqrt(m)

Nice number:

   1//5⋅√15

julia> sqrt(n)

ERROR: sqrt(2+3⋅√5) is not nice anymore!

[...]

```

There is also a macro to simplify working with nice numbers:

```julia

julia> using LinearAlgebra

julia> n = norm([4,12,3] * √2)

18.38477631085024

julia> @nice m = norm([4,12,3] * √2)

Nice number:

   13⋅√2

julia> n == m

true

```

For further examples see the examples section of the documentation,

especially the [SVD example](https://fkastner.github.io/NiceNumbers.jl/dev/example_svd/).