What are some examples of using the map method in Ruby?

What are some examples of using the map method in Ruby?

The map method in Ruby is used to transform elements in an array. For example, if you have an array of numbers and you want to square each number, you can do it like this:

numbers = [1, 2, 3, 4]
squared_numbers = numbers.map { |n| n ** 2 }
puts squared_numbers.inspect  # Output: [1, 4, 9, 16]

Can you show me another example with strings?

Sure! If you have an array of strings and you want to capitalize each string, you can use map like this:

words = ['hello', 'world']
capitalized_words = words.map(&:capitalize)
puts capitalized_words.inspect  # Output: ['Hello', 'World']

What if I want to filter the results as well?

You can combine map with select to filter results. For example, if you want to square only the even numbers:

numbers = [1, 2, 3, 4, 5]
even_squares = numbers.select(&:even?).map { |n| n ** 2 }
puts even_squares.inspect  # Output: [4, 16]