How to create a sequence of text IDs in r?

Question

My problem is to create a sequence of IDs in a vector. The vector will contain 001 to 020 then 030 to 100.

I can generate numbers by

x <-  c(1:20,30:100)

but this is not in the format I am interested.

Answer 1

x <- c(paste("00", 1:9, sep=""),paste("0", 10:99, sep=""),100)

Answer 2

As suggested by the Frank... Use sprinf for formatted output. I like the %f formatter to format numbers. It is designed to format floating point numbers. %f will be replaced by the number. You can add 0 in front of the f to get leading numbers. Or you can also define how many digits you want to have overall (in your case 3) and how many should be decimal (0 after the .). Play a little with it. It is great for formatted output, filename etc.

sprintf('%03.0f', c(1:20,30:100))