r - Divide set into two unequal, random parts -

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• how split data training/testing sets using sample function 11 answers

i writing function must divide whole set 2 smaller ones @ random. size of set determined user. try way

number <- function(z,y,p){ indeks <-split(z$y,sample(rep(1:2), c(p, z$y-p))) train <- z[indeks,] test <- z [-indeks, ] result <- list(test, train) list(result) } number(z=lipiec , y=vii,  p=200) 

however, following error pops up

 error in sample.int(length(x), size, replace, prob) :   cannot take sample larger population when 'replace = false'  

the structure of file trying divide int. , there 574 lines. value 200 not greater whole sample. 2 randomly split sets, 1 of them (test) have 200 elements, , other (train) rest of base set. have idea doing wrong?

*****edit**** after modification did follows:

number <- function(z,y,p){ df <- as.data.frame(z$y) indeks <-split(df, sample(nrow(df))<=p) train <- indeks$ test <- indeks$ str(test)} number(z=lipiec , y=vii,  p=200) 

now not know should assign test , train assign each of them 1 of parts of collection. have idea?

myfun <- function(df, n) {     split(df, sample(nrow(df))<=n) }  set.seed(1) myfun(mtcars,10)