calculating sum of lag x rows
I am trying to create a column that calculates the sum of the lag 24 rows. In this instance I have a column "Precip" that contains hourly precipitation totals. There is a second column "precipitation station" denoting from which location each value was recorded. I have sorted the columns based on "DateTime" and the "Precipitation Station". I am looking for an efficient way to sum the previous 24 ...
RVhydrA
DMR
vince_faller