Question

我正在尝试按对象（得分）的某个方面进行排序。这是我到目前为止，但我收到错误消息，如“未定义的方法得分”。

class object
    def initialize(likes, comments, score)
        @no_of_likes=likes
        @no_of_comments=comments
        @score =score
    def calculateScore
        #Assigns a score to each element of the array, based off of            algorithm
        @score = (@no_of_likes + @no_of_comments)
    end
def sortByScore()

    arr = [o1 =Object.new(40, 35, 0), o2 =Object.new(100, 2, 0), o3 = Object.new(1, 150, 0)]

    for obj in arr
        obj.calculateScore
    end
    #sorts by score
    arr = ar.sort_by &:score
    puts arr.inspect
end

Answer 1

我将你的班级改名为Obj，对象不是一个好名字。 Obj也不好。试着给这个类命名一些描述你最近的东西（Scorekeeper怎么样？）。

class Obj
  attr_reader :score

  def initialize(likes, comments, score)
    @no_of_likes = likes
    @no_of_comments = comments
    @score = score
  end

  # Assigns a score to each element of the array, based off of algorithm
  def calculateScore
    @score = (@no_of_likes + @no_of_comments)
  end
end

注意添加的行：

  attr_reader :score

这相当于：

  def score
    @score
  end

这是你缺少/未定义的方法：

arr = [Obj.new(40, 35, 0), Obj.new(1, 150, 0), Obj.new(100, 2, 0)]
arr.map(&:score)
 => [0, 0, 0]

arr.each { |obj| obj.calculateScore }
arr.map(&:score)
 => [75, 151, 102] 

arr = arr.sort_by(&:score)
arr.map(&:score)
 => [75, 102, 151]

Answer 2

如果您有这些对象的集合，

@collection.sort_by{|object| object.score}

应该做的伎俩。

Answer 3

R = Struct.new(:confusion)

Ruby = Array.new(9){R.new(rand)}
sorted = Ruby.sort_by(&:confusion)

Ruby sort_by混乱

3 个答案: