Create R Function with flexibility to reference different datasets

Question

I am trying to create a simple function in R that can reference multiple datasets and multiple variable names. Using the following code, I get an error, which I believe is due to referencing:

set.seed(123)
dat1 <- data.frame(x = sample(10), y = sample(10), z = sample(10))
dat2 <- data.frame(x = sample(10), y = sample(10), z = sample(10))

table(dat1$x, dat1$y)
table(dat2$x, dat2$y)

fun <- function(dat, sig, range){print(table(dat$sig, dat$range))}

fun(dat = dat1, sig = x, range =  y)
fun(dat = dat2, sig = x, range =  y)

Any idea how to adjust this code so that it can return the table appropriately?

Answer 1

The [[ ]] operator on data frame is similar to $ but allows you to introduce an object and look for it's value. Then outside of the function you assign " x " value to sig . if you don't put quotes there R will look for x object

fun <- function(dat, sig, range){print(table(dat[[sig]], dat[[range]]))}

fun(dat = dat1, sig = "x", range =  "y")
fun(dat = dat2, sig = "x", range =  "y")