Ruby searching through multidimensional array

Question

Learning the beauty of Ruby code and I was wondering if there is a simple/straightforward to search within a multidimensional array. I have an multi array with 4 indices that contain assorted number. I want to search though each index matching the contents agains another array...seudo codez

multi_array = [ [1,3,7], [3,1,4], [1,3,4], [0,9,2]]
numbers_looking_to_match = [1,5,9]
multi_array.each do | elmt |
  elmt.each_with_index do |elmt, idx|
    if elmt == numbers_looking_to_match.each { |e| puts "match" }
  end 
end

I want this to return a new multi array with all non matching characters removed for original multi array.

Are you trying to remove numbers from within each element of multi_array? Or throw out an element of multi_array if it doesn't contain an exact match for numbers_looking_to_match? Also, do you care about order of numbers in each element? — Josh Diehl
– Josh Diehl, Commented Oct 1, 2011 at 20:09
What I am trying to do is remove number not matching the number_looking_to_match...so if we look at the multi array and numbers_looking_to_match arrays the return of the function should provide me with a result == [[1],[1],[1],[9] but Not limited to one result. — Somethingconcon
– Somethingconcon, Commented Oct 6, 2011 at 19:32

Spotlight · Accepted Answer · 2017-07-16 18:35:10Z

6

Using Array#& for intersection,

multi_array.map {|a| a & numbers_looking_to_match }

edited Jul 16, 2017 at 18:35

Spotlight

4841 gold badge11 silver badges23 bronze badges

answered Oct 1, 2011 at 20:56

Michael Morgan

8145 silver badges6 bronze badges

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

1 Comment

Gcap Over a year ago

what if the array has mixed types? the first element in my array is a Fixnum and the rest are Arrays or Strings

ennuikiller · Accepted Answer · 2011-10-01 20:11:24Z

1

multi_array.each { |elem| numbers_looking_to_match.each { |x| elem.delete(x) if elem.include?(x)} }

answered Oct 1, 2011 at 20:11

ennuikiller

47.1k15 gold badges115 silver badges137 bronze badges

Comments

Josh Diehl · Accepted Answer · 2011-10-01 20:41:32Z

1

To scrub each element of unwanted characters:

require 'set'
multi_array=[ [1,3,7], [3,1,4], [1,3,4], [0,9,2]]
numbers_looking_to_match=Set.new([1,5,9])

scrubbed=multi_array.collect{ |el|
  numbers_looking_to_match.intersection(el).to_a
}

puts scrubbed.inspect
# prints [[1], [1], [1], [9]]

answered Oct 1, 2011 at 20:41

Josh Diehl

3,1383 gold badges34 silver badges43 bronze badges

Collectives™ on Stack Overflow

Ruby searching through multidimensional array

3 Answers 3

1 Comment

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

1 Comment

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related