New lines list into array

Question

I have a list containing new lines and I like to convert it into an array, e.g.

JAN 

FEB 

MAR

APR

MAY

into ["JAN", "FEB", "MAR", "APR", "MAY]

Any help will be appreciated. Thanks

Something like this doesn't seem to work (text_file.txt contains a list of months as above)

file = File.new("text_file.txt", "r")
while (line = file.gets)
    line.chomp 
    list = line.split(/\n/)
    puts "#{list}"
end

Solution 1

This works on 1.9.. not sure if empty? is available in 1.8 though

%(
JAN 

FEB 

MAR

APR

MAY
).split(/\n/).reject(&:empty?)

Solution 2

If you mean this kind of list

text = "JAN\nFEB\nMAR\nAPR\nMAY"

then you can convert it to array like this

text.split(/\n/) => ["JAN", "FEB", "MAR", "APR", "MAY"]

UPDATE: Second try:

text = []
File.read("text_file.txt").each_line do |line|
  text << line.chop
end
puts text => ["JAN", "FEB", "MAR", "APR", "MAY"]

Solution 3

I realize this question is several years old, but I was unable to create an array with the other answers. I was able to figure it out by using the following code. (My list was separated by a return and not a newline.)

For data separated by a return:

text = []

input = File.read("x_values.txt")
  text = input.split("\r")
puts text.to_s

If you want to split on a newline instead:

text = []
input = File.read("x_values.txt")
  text = input.split("\n")
puts text.to_s

Solution 4

I found michalfs one-line solution very helpful, though I'd like to note a subtle detail (which will probably be only interesting to ruby-newbies like myself).

If the Y of MAY is the last character in the textfile, the resulting array will look like this:

["JAN", "FEB", "MAR", "APR", "MA"]

Why so? Quoting from the String#chop ruby doc:

chop → new_str Returns a new String with the last character removed. [...] String#chomp is often a safer alternative, as it leaves the string unchanged if it doesn’t end in a record separator.

Therefore chomp seems to be more accurate in this particular case:

File.readlines("text_file.txt").map{ |l| l.chomp }.reject{ |l| l == '' }

(Yes, I only added the 'm' to michalfs solution.)

View more solutions

Comments

[Mark]

Nope, this doesnt seem to work either. I get back the same list.

[megas]

The 'text' variable contains the result, if you want to store result to file, you should write result to file.

[Clone]

how do you do if I have a line JAN 01 FEB 02 I want to store month names and their number in different arrays?

[Clone]

in other words how to strip the tab in each line.

[fny]

@Clone by matching with regular expressions

[Franco Rondini]

+1 I tested it, working without trouble on 1.8.7; 1.9.3; 2.0.0

[Cary Swoveland]

I suggest a small change to the regex to deal with "empty" lines: /\n\n*/.

[Petr Bela]

You can also use /\n+/