I need to aggregate the same values in col2 and col3, so I expect to recieve SUM in col4 and col5:
df <- data.frame("col1"="a", "col2"=c("mi", "se", "mi", "se", "ty"),
"col3"=c("re", "my", "re", "my", "my"), "col4"=c(1, 2, 3, 4, 5),
"col5"=c(1, 2, 3, 4, 5))
agg <- aggregate(df, by=list(df$col1, df$col2), FUN=sum)
The result is an error, though:
Error in Summary.factor(c(1L, 1L), na.rm = FALSE) : ‘sum’ not meaningful for factors
My expected output is
col1 col2 col3 col4 col5
1 a mi re 4 4
2 a se my 6 6
3 a ty my 5 5