How to count Ruby Array items

The following is a guest post by Rex Feng and originally appeared on his blog. Rex is currently a student a The Flatiron School. You can learn more about him here, or follow him on twitter here.

While working in Ruby, I often find myself trying to get a count of the number of times each item appears in an array. Below, I’ll show you how to create a Hash that iterates through each item in the array and counts the number of occurrences.

We have an array of animals that we want to count.

We can count them up by creating a new Hash.

Next, we want to iterate through the animals Array and set the animal_count Key as the animal name & the animal_count Value as the counter.

For each animal in animals, we’ve either created a new Key / Value pair in animal_count or incremented the Value corresponding to the animal Key.