Ruby array inject

Question

I am trying to log the average running time of 10 threads by using the inject method but it\'s giving me this error:

undefined method `+\' for #

        

Answer 1

You need to provide an initial value for inject in this case, since if you don't, the initial value is simply the first element in the array:

puts threads.inject(0) { |sum, e| sum + e.value}.to_f / threads.size

Answer 2

You didn't provide an initial value for sum in

threads.inject() { |sum, e| sum + e.value}.to_f / threads.size

Fix it with

threads.inject(0) { |sum, e| sum + e.value}.to_f / threads.size