crackpot的音标：crackpot的英式发音音标为：['krækpɒt]crackpot的美式发音音标为：['krækpɑt]...

This method does not need to be either safe or idempotent.该方法不需要安全或者等幂.In this paper , we study nonnegative generalized idempotent matrices in detail.本文给出了一般非负广义幂等矩阵的充要条件.This matrix is idempotent.这个矩阵是等幂的....