Class: Array

Inherits:
Object
  • Object
show all
Defined in:
lib/pru/core_ext/array.rb

Instance Method Summary collapse

Instance Method Details

#group_by ⇒ Object 



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# File 'lib/pru/core_ext/array.rb', line 22

def group_by
  hash = {}
  each { |x| hash[yield(x)] = x }
  hash
end

#grouped ⇒ Object 



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# File 'lib/pru/core_ext/array.rb', line 18

def grouped
  group_by { |x| x }
end

#mean(method = nil, &block) ⇒ Object 



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# File 'lib/pru/core_ext/array.rb', line 14

def mean(method = nil, &block)
  sum(method, &block) / size.to_f
end

#sum(method = nil, &block) ⇒ Object

madeofcode.com/posts/74-ruby-core-extension-array-sum



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# File 'lib/pru/core_ext/array.rb', line 3

def sum(method = nil, &block)
  if block_given?
    raise ArgumentError, "You cannot pass a block and a method!" if method
    inject(0) { |sum, i| sum + yield(i) }
  elsif method
    inject(0) { |sum, i| sum + i.send(method) }
  else
    inject(0) { |sum, i| sum + i }
  end
end