gem 'shape_up'

require 'shape_up'

include ShapeUp::Shapes

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

# 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

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

other = Triangle.new(9, 12, 15)
triangle.similar? other   # => true
triangle.congruent? other # => false