encoding a set of flags as an int in R

flag_encoding_to_int.R

gen_id <- function( v, silent=FALSE ) {
	v = sort(v)
	z <- unlist(lapply( which( chars %in% v) - 1, FUN=function(x) { bitwShiftL(1, x)}))
	total <- sum(z)
	if(!silent) {
		print(v)
		print(z)
		print(total)
	}
}

chars <- c('a', 'b', 'c', 'd', 'e', 'f', 'g')
#           1    2    4    8    16   32   64   

gen_id( sample(chars, sample(1:7, 1) ) )



# benchmark(gen_id( sample(chars, sample(1:7, 1) ) ))