Iterating Symbols

[hoffmanroni]

Hi I have many symbols and wondering if anyone has any insight on the best way to iterate them?
For instance for bollinger bands, it seems to be quite fast to calculate and a whole data set with many symbols, but if I try to filter and iterate on the dataframe it seems too slow.

Is there some way to pass the data to BollinberBand but have the calculated values separated by symbol?

Thanks!