How to add jitter in a data frame in R

Question

Input:

df = data.frame(col1 = 1:5, col2 = 5:9)
rownames(df) <- letters[1:5]


#add jitter
jitter(df) #Error in jitter(df) : 'x' must be numeric

Expected output: jitter will be added to the columns of df. Thanks!

Answer 1

jitter is a function that takes numeric as input. You cannot simply run jitter on the whole data.frame. You need to loop through the columns. You can do:

data.frame(lapply(df, jitter))

Answer 2

Jitter is to be applied to a numerical vector, not a dataframe. If you want to apply Jitter to all your columns, this should do:

apply(df, 2, jitter)

Answer 3

Just adding random numbers?

df_jit <- df + matrix(rnorm(nrow(df) * ncol(df), sd = 0.1), ncol = ncol(df))