R how can I calculate difference between rows in a data frame

Question

Here is a simple example of my problem:

> df <- data.frame(ID=1:10,Score=4*10:1)
> df
       ID Score
    1   1    40
    2   2    36
    3   3    3         


        

Answer 1

diff wants a matrix or a vector rather than a data frame. Try

data.frame(diff(as.matrix(df)))