aggregate methods treat missing values (NA) differently

Question

Here\'s a simple data frame with a missing value:

M = data.frame( Name = c(\'name\', \'name\'), Col1 = c(NA, 1) , Col2 = c(1, 1))
#   Name Col1 Col2
# 1 name          


        

Answer 1

If you want the formula version to be equivalent try this:

M = data.frame( Name = rep('name',5), Col1 = c(NA,rep(1,4)) , Col2 = rep(1,5))
aggregate(. ~ Name, M, function(x) sum(x, na.rm=TRUE), na.action = na.pass)