R: IsPrime Property

IsPrime {DescTools} | R Documentation

## IsPrime Property

### Description

Returns for a vector or matrix of positive integers a logical object of the same dimension(s) containing `TRUE` for the elements that are prime and `FALSE` otherwise.

### Usage

    IsPrime(x)

### Arguments

`x` | vector or matrix of nonnegative integers

### Details

Given a vector or a matrix of positive integers returns a vector of the same size of `FALSE` and `TRUE`. Use `which(IsPrime(1:21))` to get the positions.

### Value

logical vector

### Author(s)

Hans W. Borchers <hwborchers@googlemail.com>

### See Also

`Factorize, Primes`

### Examples

    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(IsPrime(octett))) {
            cat(octett, "\n", sep="  ")
            break
        }
    }

[Package DescTools version 0.99.25 Index]