How to count identical string elements in a Ruby array

ruby arrays count element
user398520 picture user398520 · Feb 26, 2011 · Viewed 61.5k times · Source

I have the following Array = ["Jason", "Jason", "Teresa", "Judah", "Michelle", "Judah", "Judah", "Allison"]

How do I produce a count for each identical element? 

Where:
"Jason" = 2, "Judah" = 3, "Allison" = 1, "Teresa" = 1, "Michelle" = 1?

or produce a hash Where:

Where: hash = { "Jason" => 2, "Judah" => 3, "Allison" => 1, "Teresa" => 1, "Michelle" => 1 }

Answer

Mauricio picture Mauricio · Feb 26, 2011 
names.inject(Hash.new(0)) { |total, e| total[e] += 1 ;total}

gives you

{"Jason"=>2, "Teresa"=>1, "Judah"=>3, "Michelle"=>1, "Allison"=>1}

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