Mike Hernandez

lib/event.rb

@@ -0,0 +1,57 @@
+class Event
+  attr_reader :name, :ages
+  def initialize(name, ages)
+    @name = name
+    @ages = ages
+  end
+
+  def max_age
+    max_age = 0
+    ages.each do |age|
+      if age > max_age
+        max_age = age
+      end
+    end
+    max_age
+  end
+
+  def min_age
+    min_age = 200
+    ages.each do |age|
+      if age < min_age
+        min_age = age
+      end
+    end
+    min_age
+  end
+
+  def average_age
+    total_age = ages.sum.to_f
+    number_ages = ages.length.to_f
+    average = total_age / number_ages
+    average
+  end
+
+  def standard_deviation_age
+    sum_ages = ages.sum
+    num_ages = ages.length
+    average = sum_ages.to_f / num_ages.to_f
+    step_4_ary = []
+    step_4 = ages.each do |num|
+               step_4_ary << (num.to_f - average).round(2)
+             end
+    step_4_ary_squared = []
+    step_4_ary.each do |num|
+      step_4_ary_squared << (num ** 2).round(2)
+    end
+    step_5 = 0
+    step_4_ary_squared.each do |num|
+      step_5 += num
+    end
+    step_6 = step_5.round(1)
+    step_7 = step_6/ages.count.to_f
+    standard_deviation = Math.sqrt(step_7).round(2)
+    standard_deviation
+  end
+
+end

lib/games.rb

@@ -1,6 +1,5 @@
 class Games
-  attr_reader :events,
-              :year
+  attr_reader :events, :year
 
   def initialize(year)
     @year = year

lib/standard_deviation.rb

@@ -1,5 +1,37 @@
 ages = [24, 30, 18, 20, 41]
 
+  sum_ages = ages.sum
+  num_ages = ages.length
+  average = sum_ages.to_f / num_ages.to_f
+
+  step_4_ary = []
+
+  step_4 = ages.each do |num|
+             step_4_ary << (num.to_f - average).round(2)
+           end
+
+  step_4_ary_squared = []
+
+  step_4_ary.each do |num|
+    step_4_ary_squared << (num ** 2).round(2)
+  end
+
+  step_5 = 0
+
+  step_4_ary_squared.each do |num|
+    step_5 += num
+  end
+
+  step_6 = step_5.round(1)
+
+  step_7 = step_6/ages.count.to_f
+
+  standard_deviation = Math.sqrt(step_7).round(2)
+
+  standard_deviation
+
+require "Pry"; binding.pry
+
 # Your code here for calculating the standard deviation
 
 # When you find the standard deviation, print it out

test/event_test.rb

@@ -0,0 +1,40 @@
+require 'minitest/autorun'
+require 'minitest/pride'
+require './lib/games'
+require './lib/event'
+
+class EventTest < Minitest::Test
+  def test_events_exist
+    event = Event.new("Curling", [24, 30, 18, 20, 41])
+
+    assert_instance_of Event, event
+  end
+
+  def test_it_has_a_name
+    event = Event.new("Curling", [24, 30, 18, 20, 41])
+
+    assert_equal "Curling", event.name
+  end
+
+  def test_ages_are_passed_as_an_arry
+    event = Event.new("Curling", [24, 30, 18, 20, 41])
+
+    assert_equal [24, 30, 18, 20, 41], event.ages
+  end
+
+  def test_there_is_a_max_and_min_age_and_average_ages
+    event = Event.new("Curling", [24, 30, 18, 20, 41])
+
+    assert_equal 41, event.max_age
+    assert_equal 18, event.min_age
+    assert_equal 26.6, event.average_age
+  end
+
+  def test_event_can_return_standard_deviation
+    event = Event.new("Curling", [24, 30, 18, 20, 41])
+
+    assert 8.28, event.standard_deviation_age
+  end
+
+
+end