I have an "array of arrays" that has two values included at a time.
array = [[:tuesday, 0.25], [:monday, 1], [:thursday, 0.75]]
I'd like to use the number in the "child" array to sort the "parent" array in descending order. The result would look like:
array = [[:monday, 1], [:thursday, 0.75], [:tuesday, 0.25]]
I'm not too sure where to begin here.
You can pass a block to the sort method like this:
array.sort { |a, b| b[1] <=> a[1] }
I would be inclined to write
array.sort_by(&:last).reverse
array = [['Tuesday',0.25],['Monday',1],['Thursday',0.75]]
p array.sort_by{|a| -a[1]}
# => [["Monday", 1], ["Thursday", 0.75], ["Tuesday", 0.25]]
You could use sort to return a new sorted array (saved as new_array).
new_array = array.sort{|x, y| y[1] <=> x[1]}
# => [["Monday", 1], ["Thursday", 0.75], ["Tuesday", 0.25]]
This keeps the original array unchanged.
array
# => [["Tuesday", 0.25], ["Monday", 1], ["Thursday", 0.75]]
Or you change the order of the original array by using sort!.
array.sort!{|x, y| y[1] <=> x[1]}
# => [["Monday", 1], ["Thursday", 0.75], ["Tuesday", 0.25]]
array
# => [["Monday", 1], ["Thursday", 0.75], ["Tuesday", 0.25]]
