In this letter , we introduce the rule of the linear and non - linear movement of the single pendulum , and by using the jacobian elliptic function , we educe two categories of movement fuctions of the single pendulum , the results will be some referential improtance in studying the non - linear vibrational systems 摘要介紹了單擺的線性與非線性運動規(guī)律,并利用雅可比橢圓函數(shù)法導(dǎo)出了單擺作兩種運動的方程,對研究非線性振動的系統(tǒng)有一定參考價值。