我想计算每个网格方块过去三天的降雨量,并将其添加为我的data.table中的新列.为了清楚起见,我想总结一下当前和上一天的降雨量,对于每个气象网格广场
library ( zoo )
library (data.table)
# making the data.table
rain <- c(NA, NA, NA, 0, 0, 5, 1, 0, 3, 10) # rainfall values to work with
square <- c(1,1,1,1,1,1,1,1,1,2) # the geographic grid square for the rainfall measurement
desired_result <- c(NA, NA, NA, NA, NA, 5, 6, 6, 4, NA ) # this is the result I'm looking for (the last NA as we are now on to the first day of the second grid square)
weather …