stationary test

A common used is the Augmented Dickey-Fuller test with performs a test in a J. Brownlee - Machine Learning Mastery form:

In this test, the null hypothesis states that $\varphi =1$ (a unit test). If $p-$value is low $<0.05$ we reject the null hypothesis, i.e, we assume that the dataset is stationary. Else, we accept the null hypothesis.