r - lapply on dataframe list using different column index -

i'm try feature selection on dataframe list using caret package. have different dataframes last 6 columns same. when trying apply model on single df works fine

# single dataframe mx.chem # name of single dataframe #define control    mx.control <- rfecontrol(functions=rffuncs, method = "cv", number = 10)  # run rfe      mx.results <- rfe(mx.chem[,1:22], mx.chem[,23], sizes = c(1:22), rfecontrol = mx.control) print(mex.results) 

but problem when try use lapply on list of df. code have until is

 require(mlbench)  require(caret)  mylist # df list containing 3 df    (i in 1:3) {   my.control <- rfecontrol(functions=rffuncs, method = "cv", number = 10)  # define control   longdata <- length(i)-6   idxindustry <- longdata +1   my.results <- lapply(mylist, function(x) rfe ( x[,1:longdata], x[,idxindustry], data = x, sizes =c(1:longdata), rfecontrol = my.control))   } 

i'm not sure if i'm using column index properly. have idea how fix make code work.

here 2 possible ways:

#using lapply mx.control <- rfecontrol(functions=rffuncs, method = "cv", number = 10)  rfe.lst <- lapply(mylist,             function(x) {                longdata <- ncol(x)-6                rfe ( x[,1:longdata], x[,longdata + 1],                           sizes =c(1:longdata),                           rfecontrol = mx.control)                })  #for loop mx.control <- rfecontrol(functions=rffuncs, method = "cv", number = 10)  rfe.lst <- vector("list", 3) for(i in 1:3) {   longdata <- ncol(mylist[[i]])-6   rfe.lst[[i]] <- rfe(mylist[[i]][,1:longdata], x[,longdata + 1],       sizes=c(1:longdata),       rfecontrol=mx.control) }