Question

This is a very basic question but I’m having a bit of trouble understanding Rubys hash sort method.

Basically whats happening is I’m receiving a cannot convert string to integer so my first guess is I’m sorting the array by a string (which is actually a number). The array contains hashes and I’m trying to sort it by one of the hashes values that I’ve identified with a key.

Heres how I’m sorting my array:

@receivedArray =(params[:respElementDatas])

    puts @receivedArray.class #Its definitely an array
    @sortedArray = @receivedArray.sort_by{|ed| ed["element_type_id"]}

The error I’m getting is can’t convert String into Integer on the sort line.

Naturally I assumed that

Just a quick question.
Am i right in saying that ‘ed’ is an object that is stored in the array and I’m referencing it correctly? Also any pointers on how to fix it?

Answer 1

Your @receivedArray is an array of arrays or has at least one array in it. For example:

a = [[1,2,3],[4,5,6]]
[[1, 2, 3], [4, 5, 6]]
a.sort_by { |e| e['x'] }
# TypeError: can't convert String into Integer

a = [{:a => :a},{:b => :b},[1,2,3]]
[{:a=>:a}, {:b=>:b}, [1, 2, 3]]
a.sort_by { |e| e['x'] }
# TypeError: can't convert String into Integer

a = [{'where' => 'is'},{'pancakes' => 'house'}]
[{"where"=>"is"}, {"pancakes"=>"house"}]
a.sort_by { |e| e['x'] }
# No error this time