CODEWITHSUNDEEP
rubyruby-hash
Hameed Basha
Hameed Basha

Reputation: 13

Add a value to an existing Key value pair ruby hash

My ruby script filters a log and generates a hash like this

scores = {"Rahul" => "273", "John"=> "202", "coventry" => "194"}

by skipping multiple values for a key which is obvious

log file will be like this

Rahul has 273 Rahul has 217 John has 202 Coventry has 194

Is it Possible to generate something like this

scores = {"Rahul" => "273", "Rahul" =>"217",
          "John"=> "202", "coventry" => "194"}

scores = {"Rahul" => "273","217",
          "John"=> "202", "coventry" => "194"}

Is there a way to forcefully write into a hash even though the key is already existing in the hash

I will be grateful to any help or suggestions

Upvotes: 0

Views: 3003

Answers (2)

Stefan
Stefan

Reputation: 114158

To store your scores, you could create a hash which has an empty array as its default value:

scores = Hash.new { |hash, key| hash[key] = [] }

scores['Rahul'] #=> [] <- a fresh and empty array

You can now extract the values from the log and add it to the respective key's value. I'm using scan with a block: (using the pattern from mudasobwa's answer)

log = 'Rahul has 273 Rahul has 217 John has 202 Coventry has 194'

log.scan(/(\w+) has (\d+)/) { |name, score| scores[name] << score.to_i }

scores #=> {"Rahul"=>[273, 217], "John"=>[202], "Coventry"=>[194]}

Although not required, I've converted each score to an integer before adding it to the array.

Upvotes: 1

Aleksei Matiushkin
Aleksei Matiushkin

Reputation: 121000

"Rahul has 273 Rahul has 217 John has 202 Coventry has 194".
  scan(/(\w+) has (\d+)/).group_by(&:shift)
#⇒ {"Rahul"=>[["273"], ["217"]],
#   "John"=>[["202"]],
#   "Coventry"=>[["194"]]}

For the values flattening please check the comment by Johan Wentholt below.

Upvotes: 4

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