How can filter Function be used between 2 datasets in R Studio?

Question

If I generate a sample of 30 from a data frame that has 50 observations, how can I separate the remaining 20 from the data frame of 50 using filter function? Is it possible to use the filter function between two data frames? If so, then how?

Thanks in advance.

Answer 1

Here is an example:

# dummy data
dat <- data.frame(x = 1:10,
                  y = letters[1:10], stringsAsFactors = FALSE)

Create a sample index, set a seed for reproducibility.

set.seed(1)
idx <- sort(sample(1:nrow(dat), size = 6, replace = FALSE))
idx
#[1] 2 3 4 5 7 8

Subset your data frame

dat[idx, ]
#  x y
#2 2 b
#3 3 c
#4 4 d
#5 5 e
#7 7 g
#8 8 h

Get the rows that are not in idx

dat[-idx, ]
#    x y
#1   1 a
#6   6 f
#9   9 i
#10 10 j