ruby-幫助需要將數組轉換為特定類型的數組，將鍵復制為列表中的[key，value]

Question

我想將數組轉換為特定類型的數組。

array = [“ Project”，“ Publication”]

進入

array_of_arrays = [[“ Project”，“ Project”]，[“ Publication”，“ Publication”]]

該數組不僅限於大小2。 它的列表越來越多，因此需要尋找一些函數將其轉換為array_of_arrays。

感謝任何幫助。

Answer 1

def replicate(arr, n)
  arr.map { |e| [e]*n }
end

replicate(["Project", "Publication"], 2)
  #=> [["Project", "Project"], ["Publication", "Publication"]]
replicate(["Project", "Publication"], 3)
  #=> [["Project", "Project", "Project"], ["Publication", "Publication", "Publication"]]
replicate([["ProjectA", "ProjectB"], "Publication"], 2)
  #=> [[["ProjectA", "ProjectB"], ["ProjectA", "ProjectB"]], ["Publication", "Publication"]

Answer 2

地圖可以很輕松地處理此問題。

a = ["Project", "Publication"]
a.map{|x| [x,x]}
#=> [["Project", "Project"], ["Publication", "Publication"]]