module Enumerable

Public Instance Methods

drop_last(n) click to toggle source
# File lib/flash_extensions/extensions/enumerable_extension.rb, line 9
def drop_last(n)
  array = to_a

  return array if n > array.size
  array[0...(array.size - n)]
end
drop_last_while() { |value| ... } click to toggle source
# File lib/flash_extensions/extensions/enumerable_extension.rb, line 16
def drop_last_while
  return to_enum(:drop_last_while) unless block_given?

  result   = []
  dropping = true
  reverse_each do |value|
    result.unshift(value) unless dropping &&= yield(value)
  end
  result
end
exactly?(n) { |*o| ... } click to toggle source
# File lib/flash_extensions/extensions/enumerable_extension.rb, line 27
def exactly?(n)
  found_count = 0

  if block_given?
    each do |*o|
      found_count += 1 if yield(*o)
    end
  else
    each do |o|
      found_count += 1 if o
    end
  end

  (found_count > n) ? false : n == found_count
end
frequencies() click to toggle source
# File lib/flash_extensions/extensions/enumerable_extension.rb, line 43
def frequencies
  each_with_object(Hash.new(0)) { |e, a| a[e] += 1 }
end
max(identity=0) click to toggle source
# File lib/flash_extensions/extensions/enumerable_extension.rb, line 47
def max(identity=0)
  size > 0 ? sort.last : identity
end
mean(identity=0) click to toggle source
# File lib/flash_extensions/extensions/enumerable_extension.rb, line 55
def mean(identity=0)
  collection_size = size
  collection_size > 0 ? inject(:+) / collection_size.to_f : identity
end
median(identity=0) click to toggle source
# File lib/flash_extensions/extensions/enumerable_extension.rb, line 60
def median(identity=0)
  collection_size   = size
  collection_sorted = sort

  if collection_size > 0
    if collection_size % 2 == 0
      (collection_sorted[(collection_size / 2) -1] + collection_sorted[collection_size / 2]) / 2.0
    else
      collection_sorted[collection_size / 2]
    end
  else
    identity
  end
end
min(identity=0) click to toggle source
# File lib/flash_extensions/extensions/enumerable_extension.rb, line 51
def min(identity=0)
  size > 0 ? sort.first : identity
end
mode(identity=0) click to toggle source
# File lib/flash_extensions/extensions/enumerable_extension.rb, line 75
def mode(identity=0)
  if size > 0
    frequency_distribution = inject(Hash.new(0)) { |h, v| h[v] += 1; h }
    frequency_top_2        = frequency_distribution.sort { |a, b| b[1] <=> a[1] }.take(2)

    if frequency_top_2.length == 1
      frequency_top_2.first.first
    elsif frequency_top_2.first.last == frequency_top_2.last.last
      nil
    else
      frequency_top_2.first.first
    end
  else
    identity
  end
end
range(identity=0) click to toggle source
# File lib/flash_extensions/extensions/enumerable_extension.rb, line 92
def range(identity=0)
  collection_sorted = sort
  size > 0 ? collection_sorted.last - collection_sorted.first : identity
end
several?() { |*o| ... } click to toggle source
# File lib/flash_extensions/extensions/enumerable_extension.rb, line 97
def several?
  found_count = 0

  if block_given?
    each do |*o|
      found_count += 1 if yield(*o)
    end
  else
    each do |o|
      found_count += 1 if o
    end
  end

  (found_count > 1) ? true : false
end
standard_deviation() click to toggle source
# File lib/flash_extensions/extensions/enumerable_extension.rb, line 113
def standard_deviation
  return 0 if length < 2
  Math.sqrt(variance)
end
sum(identity=0) click to toggle source
# File lib/flash_extensions/extensions/enumerable_extension.rb, line 4
def sum(identity=0)
  inject(:+) || identity
end
take_last(n) click to toggle source
# File lib/flash_extensions/extensions/enumerable_extension.rb, line 118
def take_last(n)
  array = to_a

  return array if n > array.size
  array[(array.size - n)..-1]
end
take_last_while() { |e| ... } click to toggle source
# File lib/flash_extensions/extensions/enumerable_extension.rb, line 125
def take_last_while
  return to_enum(:take_last_while) unless block_given?

  result = []
  reverse_each { |e| yield(e) ? result.unshift(e) : break }
  result
end
variance() click to toggle source
# File lib/flash_extensions/extensions/enumerable_extension.rb, line 133
def variance
  collection_length = length

  return 0 if collection_length <= 1
  sum = inject(0) { |accumulator, value| accumulator + (value - mean) ** 2 }
  sum / (collection_length.to_f - 1)
end