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rubysortingarray-multisort

Multisort using Ruby

My data is in the form of:

a = [
      {
        "a_id":101,
        "a_value":100000.0,
        "a_quantity":360.0
      },
      {
        "a_id":108,
        "a_value":110000.0,
        "a_quantity":210.0
      },
      {
        "a_id":104,
        "a_value":105000.0,
        "a_quantity":310.0
      }
    ]

I would like the data to be sorted in descending order of a_value. I have tried:

a.sort_by {|k| k[:a_value] }.reverse

But it does not get sorted.

Solution

  • What you have works. Just don't forget to assign the sorted collection to a variable (sort_by and reverse do not change the collection).

    Bonus: here's arguably a nicer version (one pass, instead of two)

    a.sort_by{ |v| -v[:a_value] }