how to pass several columns to funs

[Victsz]

x<-data.table(a=c(1:100),b=c(-1:-100))
winScan(x = x,
groups = NULL,
position = NULL,
values = c("a", "b"),
win_size = 100,
win_step = 50,
funs =function(x,y){
sum(x*y)
})
for the funs param, how to pass several columns ?

[tavareshugo]

At the moment this is not supported.

For that specific case, maybe you can first create a column with the multiplied a and b columns, and then pass the sum function to winScan.

For example:

x <- data.table(a=c(1:100),b=c(-1:-100))

x$c <- x$a * x$b

winScan(x = x,
        groups = NULL,
        position = NULL,
        values = "c",
        win_size = 100,
        win_step = 50,
        funs = "sum")