gmp_lib.mpz_probab_prime_p Method

GMP Native Interface for .NET

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gmp_libmpz_probab_prime_p Method
Determine whether n is prime.

Namespace:  Math.Gmp.Native
Assembly:  Math.Gmp.Native (in Math.Gmp.Native.dll) Version: 1.0.0.0 (1.0.0.0)
Syntax
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public static int mpz_probab_prime_p(
	mpz_t n,
	int reps
)
Public Shared Function mpz_probab_prime_p ( 
	n As mpz_t,
	reps As Integer
) As Integer
public:
static int mpz_probab_prime_p(
	mpz_t^ n, 
	int reps
)
static member mpz_probab_prime_p : 
        n : mpz_t * 
        reps : int -> int

Parameters

n
Type: Math.Gmp.Nativempz_t
The operand integer.
reps
Type: SystemInt32
The number of Miller-Rabin probabilistic primality tests to perform.

Return Value

Type: Int32
Return 2 if n is definitely prime, return 1 if n is probably prime (without being certain), or return 0 if n is definitely non-prime.
Remarks

This function performs some trial divisions, then reps Miller-Rabin probabilistic primality tests. A higher reps value will reduce the chances of a non-prime being identified as “probably prime”. A composite number will be identified as a prime with a probability of less than 4^(-reps). Reasonable values of reps are between 15 and 50.

Examples
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// Create, initialize, and set the value of n to 12.
mpz_t n = new mpz_t();
gmp_lib.mpz_init_set_ui(n, 12U);

// Assert that n is a composite number.
Assert.IsTrue(gmp_lib.mpz_probab_prime_p(n, 25) == 0);

// Release unmanaged memory allocated for n.
gmp_lib.mpz_clear(n);
' Create, initialize, and set the value of n to 12.
Dim n As New mpz_t()
gmp_lib.mpz_init_set_ui(n, 12UI)

' Assert that n is a composite number.
Assert.IsTrue(gmp_lib.mpz_probab_prime_p(n, 25) = 0)

' Release unmanaged memory allocated for n.
gmp_lib.mpz_clear(n)

No code example is currently available or this language may not be supported.

No code example is currently available or this language may not be supported.

See Also
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