Class: Statistic::Base

Inherits:

Object

• Object
• Statistic::Base

Defined in:

lib/statistic.rb

Direct Known Subclasses

StandardDeviation

Instance Attribute Summary

• #nums ⇒ Object readonly

  Returns the value of attribute nums.

Instance Method Summary

• #average ⇒ Object

  平均.

• #deviations ⇒ Object

  偏差: 平均からの差異.

• #initialize(nums) ⇒ Base constructor

  A new instance of Base.

• #variances ⇒ Object

  分散: 偏差の2乗和の平均.

Constructor Details

#initialize(nums) ⇒ Base

Returns a new instance of Base.

# File 'lib/statistic.rb', line 5

def initialize(nums)
  @nums = nums
end

Instance Attribute Details

#nums ⇒ Object (readonly)

Returns the value of attribute nums.

# File 'lib/statistic.rb', line 9

def nums
  @nums
end

Instance Method Details

#average ⇒ Object

平均

# File 'lib/statistic.rb', line 12

def average
  nums.reduce(:+) / nums.length
end

#deviations ⇒ Object

偏差: 平均からの差異

# File 'lib/statistic.rb', line 17

def deviations
  nums.map {|num| num - average }
end

#variances ⇒ Object

分散: 偏差の2乗和の平均

# File 'lib/statistic.rb', line 22

def variances
  results = deviations.map {|dev| dev ** 2 }
  results.reduce(:+) / results.length
end