Module: Enumerable

Defined in:
lib/rails_extensions/enumerable.rb

Instance Method Summary collapse

Instance Method Details

#mean(init = 0.0, &block) ⇒ Object

Calculates a mean of the elements in the enumerable. [1, 2, 3, 4, 5].mean # => 3.0



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# File 'lib/rails_extensions/enumerable.rb', line 6

def mean(init = 0.0, &block)
  return init if empty?

  if block_given?
    map(&block).mean(init)
  else
    sum(init) / size.to_f
  end
end

#with_gap_index(offset = 0, with_identifier: false, &block) ⇒ Object

Calculates the position of values allowing gaps. The return value is an array of arrays, each containing the original value and its position. If each values has an identifier, set the identifier as the first element of value and use with_identifier parameter.

{a:2, b:3, c:5, d:2}.with_gap_index(with_identifier: true)  # =>
[[:a, 2, 0], [:d, 2, 0], [:b, 3, 2], [:c, 5, 3]]



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# File 'lib/rails_extensions/enumerable.rb', line 22

def with_gap_index(offset = 0, with_identifier: false, &block)
  if block_given?
    map(&block).with_gap_index(offset, with_identifier: with_identifier)
  else
    new_array = []
    current_pos = offset

    each_with_index do |ele, idx|
      same_as_previous = with_identifier ? ele.second == self[idx - 1].second : ele == self[idx - 1]
      current_pos = idx + offset unless same_as_previous
      new_array.push([ele, current_pos].flatten)
    end
    new_array
  end
end