lapply and mutate_all/for loops

Question

I have several data frames within a list which I have to modify by normalizing all the data, in all columns (basically, divide each row/column by the sum of the number of that c

Answer 1

You can just use your described function and adapt for the function argument. In dplyr, the . stands, in this case, for the variable. The ~ defines a formula.

samples <- lapply(names(samplelist), function(processing){
  aux <- read.csv(samplelist[[processing]], header = T, sep = "") %>% 
    mutate_all(~./sum(.))
})