restrics loop db function to loop only, simplifies pandas inside loop (now produces a series which get_pred assumes, even tho it worked fine with single-row dataframe), moved err calc and results saving to main
restrics loop db function to loop only, simplifies pandas inside loop (now produces a series which get_pred assumes, even tho it worked fine with single-row dataframe), moved err calc and results saving to main

opotowsky/learn-me-fuel,opotowsky/learn-me-fuel