ruby on rails - How to add up the number representations of the objects of the hashes in an array of hashes?

Question

An array of hashes like

  [{color: "red", size: "large"},{color: "blue", size: "small"},{color: purple, size: "medium"},{color: "pink", size: "small"}]

Also another hash:

  {small: 1, medium: 2, large: 3, x_large: 4}

How would someone replace all the sizes by their respective numbers and sum up those numbers?

The problem could be solved manually by replacing the numbers with the sizes like so:

 [{color: "red", size: 3},{color: "blue", size: 1},{color: purple, size: 2},{color: "pink", size: 1}]

Then adding them up the number representation of the sizes would output: 7

Answer 1

Iterate over your first array, replace :size with the corrospoding size from the second array:

arr = [{color: "red", size: "large"},{color: "blue", size: "small"},{color: "purple", size: "medium"},{color: "pink", size: "small"}]

sizes =   {small: 1, medium: 2, large: 3, x_large: 4}


arr.each do |x|
  x[:size] = sizes[x[:size].to_sym]
end