Table by row with R

Question

I would like to tabulate by row within a data frame. I can obtain adequate results using table within apply in the following example:

Answer 1

Here's a table solution:

table(
    rep(rownames(df.1),5),
    unlist(df.1[,4:8]),
    useNA="ifany")

This gives

    0 1 2 10 20 200 
  1 3 1 1  0  0   0    0
  2 0 0 0  3  1   0    1
  3 0 0 0  0  0   3    2
  4 0 0 0  0  0   0    5

...and for your df.2:

    0 1 2 
  1 5 0 0    0
  2 0 5 0    0
  3 0 0 5    0
  4 0 0 0    5

Well, this is a solution unless you really like having a list of tables for some reason.