Create a sequence of numbers from a repeating set (e.g. months)-CodePudding

Is there a simple, base r approach to create a sequence of numbers from a broader REPEATING set? For instance, thinking of months of the year, how can I create a sequence based on start /end months such that:

>fx(5:10)
5, 6, 7, 8, 9, 10

but also that

>fx(10:3)
10, 11, 12, 1, 2, 3

I know this is possible based on a few lines of inelegant code, but I am sure there is something simple and concise out there.

CodePudding user response：

This isn't very elegant, but it is a single line that does the trick, as long as the sequence is a set of integers from 1:m.

fx <- function(f, l, m) (y <- (1:m)[c(f:m, 2:f - 1)])[1:which(y == l)]

> fx(5, 10, m = 12)                                                                                                   
[1]  5  6  7  8  9 10                                                                                                 
> fx(10, 3, m = 12)                                                                                                   
[1] 10 11 12  1  2  3

CodePudding user response：

One option using the modulo:

f <- function(start, end, max) (seq(start, end   (end < start) * max) - 1) %% max   1

f(5, 10, 12)
[1]  5  6  7  8  9 10

f(10, 3, 12)
[1] 10 11 12  1  2  3