Four diagnosis models are described as boolean equations, and some related problems are discussed based on boolean equations such as optimal diagnosis, all consistent fault patterns, absolute fault-free and faulty machines etc . next the four models are described as linear equations and then matlab can be used in equation diagnosis 對基于非齊次線性方程組的診斷進行了進一步的討論,對所有四種診斷模型均表示為非齊次線性方程組的形式,將matlab用于方程的診斷;并對已有的幾種不同類型的方程在診斷中的應(yīng)用進行了比較。