ShapeUp
A Pure-Ruby library for interacting with shapes. So far, only triangles are supported, but maybe more will come later.
Installation
Add this line to your application's Gemfile:
gem 'shape_up'
And then execute:
$ bundle
Or install it yourself as:
$ gem install shape_up
Usage
There will eventually be a simple command-line utility useful for very basic operations, but for now the library can only be used in irb
or in some other Ruby code.
To get started with the ShapeUp shapes library do the following:
require 'shape_up'
This isn't strictly required, but it makes working with shapes a whole lot easier:
include ShapeUp::Shapes
From here, the Triangle class provides most of the useful capabilities of this library:
triangle = Triangle.new(3, 4, 5)
triangle.right? # => true
triangle.oblique? # => false
triangle.obtuse? # => false
triangle.acute? # => false
triangle.scalene? # => true
triangle.equilateral? # => false
triangle.isosceles? # => false
triangle.angle_a # => #<ShapeUp::Angle:0x007f8ce2025f5...
triangle.angle_a.degrees # => 36.8698976458
triangle.angle_a.radians # => 0.6435011088
triangle.side_c # => #<ShapeUp::Side:0x009e6fe21354d...
triangle.side_c.length # => 5
triangle.side_c.altitude # => 2.4
triangle.area # => 6.0
triangle.perimeter # => 12
triangle.semiperimeter # => 6.0
triangle.inradius # => 1.0
Triangle values default to a precision of 10 decimal places, though this can be overridden, even on an existing Triangle:
# Change an existing Triangle's precision
less_precise = triangle.to_precision(6)
less_precise.angle_a.degrees # => 36.869898
more_precise = triangle.to_precision(12)
more_precise.angle_a.degrees # => 36.869897645844
# Set a Triangle's precision on creation
# Note that _more_ precision can lead to unusual rounding errors
special_right = Triangle.new(1, 1, Math.sqrt(2), precision: 13)
special_right.side_c.length # => 1.4142135623731
Triangles can also be split by bisecting an angle by its label:
triangle.angle_c.degrees # => 90.0
abd, acd = triangle.bisect_on_angle(:c)
abd.area # => 2.5714285714
acd.area # => 3.4285714286
triangle.area == (abd.area + acd.area) # => true
abd.angle_a.degrees # => 45.0
# This is the length of the bisector
abd.side_c.length # => 2.4243661069
acd.side_c.length # => 2.4243661069
Triangles can also be compared:
other = Triangle.new(9, 12, 15)
triangle.similar? other # => true
triangle.congruent? other # => false
Development
After checking out the repo, run bin/setup
to install dependencies. Then, run rake spec
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 tags, and push the .gem
file to rubygems.org.
Contributing
Bug reports and pull requests are welcome on GitHub at https://github.com/jgnagy/shape_up.
License
The gem is available as open source under the terms of the MIT License.