Sha256: 58f8b14668e206173023e37834f4a909821bfda3d1880419a1f299bab1efff6e
Contents?: true
Size: 875 Bytes
Versions: 219
Compression:
Stored size: 875 Bytes
Contents
library(magrittr)
# Determine whether the number is valid.
is_valid <- function(input) {
# Strip spaces, check length & check for invalid characters
input_vector <- gsub(pattern = " ", replacement = "", input) %>%
strsplit("") %>%
unlist()
if (length(input_vector) < 2 || any(grepl("[^[:digit:]]", input_vector))) {
return(FALSE)
}
# Convert to numeric
num_vector <- as.numeric(input_vector)
# Double every second digit starting from the right
num_vector <- rev(num_vector)
num_vector[seq(2, length(num_vector), 2)] <-
num_vector[seq(2, length(num_vector), 2)] * 2
# Subtract 9 if > 9 (can apply to all since no
# digit can be greater than 9 before doubling)
num_vector <- ifelse(num_vector > 9, num_vector - 9, num_vector)
# Check checksum is divisible by 10
sum(num_vector) %% 10 == 0
}
Version data entries
219 entries across 219 versions & 1 rubygems