isprime Property
Vectorized version, returning for a vector or matrix of positive integers a vector of the same size containing 1 for the elements that are prime and 0 otherwise.
isprime(x)
x |
vector or matrix of nonnegative integers |
Given an array of positive integers returns an array of the same size of 0 and 1, where the i indicates a prime number in the same position.
array of elements 0, 1 with 1 indicating prime numbers
x <- matrix(1:10, nrow=10, ncol=10, byrow=TRUE)
x * isprime(x)
# Find first prime number octett:
octett <- c(0, 2, 6, 8, 30, 32, 36, 38) - 19
while (TRUE) {
octett <- octett + 210
if (all(as.logical(isprime(octett)))) {
cat(octett, "\n", sep=" ")
break
}
}Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.