Calculate Rate of Change Grouped by Column
I, like many others I suppose, are looking at the COVID-19 data (I got mine from https://raw.githubusercontent.com/nytimes/covid-19-data/master/us-states.csv). I would like to plot the daily change in confirmed cases by State. I've been able to work it out by first sorting the data by State, and then calculating the deltas: If(:state == Lag(:state, 1),
:cases - Lag(:cases, 1)
)But is there any wa...
vince_faller