ruby - How to dump a 2D array directly into a CSV file? -


i have 2d array:

arr = [[1,2],[3,4]]

i do:

csv.open(file) |csv|    arr.each |row|      csv << row   end end

is there easier or direct way of doing other adding row row?

assuming array numbers (no strings potentially have commas in them) then:

file.open(file,'w'){ |f| f << arr.map{ |row| row.join(',') }.join('\n') }

one enormous string blatted disk, no involving csv library.

alternatively, using csv library correctly escape each row:

require 'csv' # #to_csv automatically appends '\n', don't need in #join file.open(file,'w'){ |f| f << arr.map(&:to_csv).join }

if have , code bothers you, monkeypatch in:

class csv   def self.dump_array(array,path,mode="rb",opts={})     open(path,mode,opts){ |csv| array.each{ |row| csv << row } }   end end csv.dump_array(arr,file)

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