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John Steer-Fowler
John Steer-Fowler
Courses Plus Student 11,734 Points

Accessing an Array of Hashes - Can anyone help?

I am currently creating a Ruby program and have run into an issue that I am unable to solve.

I have an array of hashes that holds a lot of the information in my program. For example:

array = [{ name: "Jack", gender: "Male", age: 30 }, { name: "Wendy", gender: "Female", age: 42 }, { name: "Julie", gender: "Female", age: 29 }]

I know that I can access the individual hashes like so:

array.each do |person|
   puts person[:age]

What I am trying to achieve is to find out which value of the 'age' key is the highest, and then assign that age to a variable called 'highest_age'

I have been trying something like this:

age = array.select { |person| person[:age] }
highest_age = age.max

This is not working for me. Can anybody help at all? Would appreciate any help.

The result should be that the 'highest_age' variable contains the integer 42 as that is the highest age of the three ages I have in my array.

Thanks in advance

Jason Seifer - would appreciate your help if no one else can help.

3 Answers

Hi John, You can access the youngest person with this:

oldest = array.max_by {|person| person[:age]}

=> {:name=>"Wendy", :gender=>"Female", :age=>42}

But to access the value of the :age key, use this:

highest_age = array.max_by do |person| person[:age] end[:age]

=> 42

John Steer-Fowler
John Steer-Fowler
Courses Plus Student 11,734 Points

Sam, what has taken me 3 hours of tinkering you have solved in 20 seconds...

Thank you kind sir :D and thank you max_by Enumerable!

John, I realized I had labeled that first snipped "youngest", rather than oldest. I also edited my answer to yield the final answer 42. Refresh the page and it should come up.

John Steer-Fowler
John Steer-Fowler
Courses Plus Student 11,734 Points

I guessed you meant 'oldest', so don't worry :D

Thank you Sam. I would like to buy you a drink :P

Look me up next time you're in Portland, OR