## generate some variables
# create a vector
var1 <- 1:30
# add NA at random places
var1[runif(7, 1, 30)] <- NA
# pinpoint NAs
pin.na(var1)
# create a matrix
var2 <- matrix(runif(100, 10, 99), nrow = 10)
# add NA at random places
var2[runif(9, 1, 100)] <- NA
# pinpoint NAs
pin.na(var2)
## define your own missing values:
var2[runif(5, 1, 100)] <- "."
pin.na(var2, na.value = c(NA, "."))
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