In the docs, there is the same explanation for using rolling windows as when using Pandas. Although, in the case of BigFrames only a int is accepted while the docs state different. In this way, I can't use something like a str (7d) or a timedelta. These options are pretty vital to the rolling method in Pandas. Is there something I am overlooking (I looked in the source code of BigFrames and it seems that only an int is accepted as its arguments).