In the paper, the criterion of the white exponential law of a discrete function is given after discussing the necessary and sufficient conditions of a continuous function being an exponential function.
在此基础上 ,给出了灰指数律判别方法 ,对于固定的分量增量 ,离散函数的实际熵趋于最大熵时 ,此离散函数具有灰指数律 。