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isprime(::BigInt, ?)

isprime(x::BigInt, [reps = 25]) -> Bool

Probabilistic primality test. Returns true if x is prime; and false if x is not prime with high probability. The false positive rate is about 0.25^reps. reps = 25 is considered safe for cryptographic applications (Knuth, Seminumerical Algorithms).

julia> isprime(big(3))
true

Examples

The isprime(::Integer) function in Julia determines whether a given integer x is prime or not. It returns true if x is prime and false otherwise.

julia> isprime(3)
true

Here are some common examples of using the isprime function:

1. Check if a number is prime:

   julia> isprime(7)
   true

2. Verify if a large number is prime:

   julia> isprime(10^9 + 7)
   true

3. Identify non-prime numbers:

   julia> isprime(10)
   false

4. Use the function in a conditional statement:

   julia> num = 13;
   julia> if isprime(num)
             println("$num is prime")
         else
             println("$num is not prime")
         end

Please note that the isprime function works only with integers. If a non-integer value is passed, an error will occur.

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