NumberToColor

Color code a value within a numerical range.

All colors are customizable, but defaults to a linear gradient between red (#ef4444 "negative") and blue (#0ea5e9 "positive"), with white as the midpoint for "neutral" or average.

Usage

Params

  • value: The numerical value to color code for.

  • domain: The numerical domain, or "range", for the color gradient. This can be a 2 or 3-item array. In a 2-item array, the midpoint is automatically set as the "neutral" value/color. In a 3-item array, you can set the midpoint to be anywhere between the first and last item (e.g., [0, 5, 7]).

  • neutral_color / positive_color / negative_color: (optional) Custom colors that can be passed in to override the defaults. These can be hex or RGB codes.


To get started, require the gem in your file.


require 'number_to_color'

Examples

Simple linear range between two numbers

ColorCode.new(value: 2, domain: [1, 3]).to_hex

// #ffffff (neutral color)

Non-linear range

ColorCode.new(value: 5, domain: [1, 5, 7]).to_hex

// #ffffff (neutral color)

Inverted domain

ColorCode.new(value: 1, domain: [7, 1]).to_hex

// #0ea5e9 ("good" color)

Custom "positive" color

ColorCode.new(value: 1, domain: [0, 1], positive_color: '#ffffff").to_hex

// #ffffff (our new "positive" color)

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake test to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and the created tag, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/nonlocalize/number_to_color.

License

The gem is available as open source under the terms of the MIT License.