code: def classify(in_x, groups, labels, k):
      
      # 计算欧式距离
      gl = array_len(groups)
      tmp = tile(in_x, (gl, 1)) - groups
      tmp = exponential_operation(tmp, 2)
      tmp = array_sum(tmp)
      tmp = exponential_operation(tmp, 0.5)
  
      # 得到排序后的数组的索引
      arg = argsort(tmp)
  
      # 计算最相似数据的前k个数据的分类次数
      cc = odict()
      for i in range(k):
          # 获得类别次数
          la = labels[arg[i]]
          cc[la] = cc.get(la, 0) + 1
      return max(cc)
docs: 分类