Method: Enumerable#frequency

Defined in:
lib/core/facets/enumerable/frequency.rb

#frequency ⇒ Object

Generates a hash mapping each unique symbol in the array to the absolute frequency it appears.

[:a,:a,:b,:c,:c,:c].frequency  #=> {:a=>2,:b=>1,:c=>3}

CREDIT: Brian Schröder

– NOTE: So why not use #inject here? e.g. …

inject(Hash.new(0)){|p,v| p[v]+=1; p}

Because it is a fair bit slower than the traditional definition. ++



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# File 'lib/core/facets/enumerable/frequency.rb', line 18

def frequency
  p = Hash.new(0); each{ |v| p[v] += 1 }; p

end