Class: Geometry::Triangle

Inherits:
Object
  • Object
show all
Defined in:
lib/geometry-bgw.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(a, b, c) ⇒ Triangle

Returns a new instance of Triangle.



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# File 'lib/geometry-bgw.rb', line 7

def initialize(a,b,c)
  @a = a
  @b = b
  @c = c
end

Instance Attribute Details

#a ⇒ Object

Returns the value of attribute a.



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# File 'lib/geometry-bgw.rb', line 5

def a
  @a
end

#b ⇒ Object

Returns the value of attribute b.



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# File 'lib/geometry-bgw.rb', line 5

def b
  @b
end

#c ⇒ Object

Returns the value of attribute c.



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# File 'lib/geometry-bgw.rb', line 5

def c
  @c
end

Instance Method Details

#angles ⇒ Object 



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# File 'lib/geometry-bgw.rb', line 40

def angles
  angles = []

  def law_of_cosines(a, b, c)
  cos = ((a ** 2) + (b ** 2) - (c ** 2)).to_f / (2 * a * b).to_f
  (Math.acos(cos) / (Math::PI / 180)).round(2)
  end
  
  angles << law_of_cosines(@b, @c, @a)
  angles << law_of_cosines(@c, @a, @b)
  angles << law_of_cosines(@a, @b, @c)
  return angles

end

#area ⇒ Object 



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# File 'lib/geometry-bgw.rb', line 29

def area
  if valid?
    semi_perimeter = self.perimeter.to_f / 2
    num_to_sqrt = semi_perimeter * (semi_perimeter - @a) * (semi_perimeter - @b) * (semi_perimeter - @c)
    area = Math.sqrt(num_to_sqrt)
    return area.round(2)
  else
    puts "Not a valid triangle"
  end
end

#law_of_cosines(a, b, c) ⇒ Object 



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# File 'lib/geometry-bgw.rb', line 43

def law_of_cosines(a, b, c)
cos = ((a ** 2) + (b ** 2) - (c ** 2)).to_f / (2 * a * b).to_f
(Math.acos(cos) / (Math::PI / 180)).round(2)
end

#perimeter ⇒ Object 



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# File 'lib/geometry-bgw.rb', line 21

def perimeter
  if valid?
    @a + @b + @c
  else
    puts "Not a valid triangle"
  end
end

#valid? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/geometry-bgw.rb', line 13

def valid?
  if (@a + @b > @c) && (@b + @c > @a) && (@c + @a > @b)
    true
  else
    false
  end
end