comparing index values in an array

Question

I have an array that looks like this

ranking_array = ['NC', '40', '30/5', '30/4', '30/3', '30/2', '30/1', '30', '15/5', '15/4', '15/3', '15/2', '15/1', '15', '5/6', '4/6', '3/6', '2/6', '1/6', '0', '-2/6', '-4/6', '-15', '-30']

I have also a model user, my user has a ranking which is a value that is contained in ranking_array.

I have a model tournament with a max_ranking and a min_ranking which are both values contained in the ranking_array.

A user can only subscribe to a tournament if

tournament.min_ranking<=user.ranking <= tournament.max_ranking

I need a way to compare the value of rankings (ie ranking_array index because ranking_array is sorted from the lowest to highest ranking)

Thus, I need to write down a method comparing these values indexes:

if current_user.ranking_index > tournament.max_ranking_index
  flash[:alert] = "Vous n'avez pas le classement requis pour vous inscrire dans ce tournoi"
elsif current_user.ranking_index < tournament.min_ranking_index
  flash[:alert] = "Vous n'avez pas le classement requis pour vous inscrire dans ce tournoi"

How can I achieve that with each_with_index ?

It's unclear what you're trying to achieve. How do you want to use the each_with_index in this context? — nesiseka
– nesiseka, Commented Jun 21, 2015 at 16:00
I have the ranking_array contaning all my rankings. My tournament object has a min and max ranking. A user can only subscribe to a tournament if tournament.min_ranking<=user.ranking <= tournament.max_ranking. I need a way to compare the value of rankings (ie ranking_array index because ranking_array is sorted from the lowest to highest ranking — David Geismar
– David Geismar, Commented Jun 21, 2015 at 16:15

stephhippo · Accepted Answer · 2015-06-21 16:23:23Z

3

I think I understand what you're trying to achieve: You want to make sure that a player has a ranking between the minimum and maximum ranking, but you only store the ranking in each model as a string. The ranking array has rankings in ascending order, but I'm not sure if #each_with_index is the way to go. The other answer is cleaner. You could also read about Rails built-in enum class that would make this cleaner and easier to understand when a new or outside developer is reading it.

Your question was about how to do this with each_with_index though, so something like this would be what you want.

ranking_array.each_with_index do |ranking, i|
  return i if ranking == current_user.ranking
end

Also, both of your alerts are flashing the same message. If this is intentional and not a typo, you could combine your if statement like this:

if current_user.ranking_index > tournament.max_ranking_index || current_user.ranking_index < tournament.min_ranking_index
  flash[:alert] = "Vous n'avez pas le classement requis pour vous inscrire dans ce tournoi"
end

answered Jun 21, 2015 at 16:23

stephhippo

1044 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Aleksei Matiushkin Over a year ago

Sidenote: if a > b || a < c is to be written unless (c..b) === a using triple-equal Range operator.

Cary Swoveland Over a year ago

Note Range#=== is the same as Range#include?, which, if the elements of the range are numeric, is the same as Range#cover?.

nesiseka · Accepted Answer · 2015-06-21 16:18:56Z

2

If you want to get the indexes of the rankings, just call .index on the ranking_array.

ranking_array.index(current_user.ranking)

answered Jun 21, 2015 at 16:18

nesiseka

1,3289 silver badges22 bronze badges

Collectives™ on Stack Overflow

comparing index values in an array

2 Answers 2

2 Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

2 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related