I'm trying to get a hang of this pipeline business. It's a steep learning curve because I can't debug it by peeking into dataframes at every step. At any rate, could someone knowledgeable and generous review my code and tell me if it's actually doing what I'm asking it to do which is to sum the rank of all the ratios and return the best ranked 20 stocks?
Also, it's really slow, is there any way to improve the speed?
Is it also possible instead of ranking, to provide a percentile?