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ISPRIME

Purpose:

Returns 1 for each series value that is prime, else 0.

Syntax:

ISPRIMES(series)

Returns:

A series or scalar is the input is a scalar.

Example:

W1: 0..8

W2: isprime(W1)

W2 contains the series {0, 0, 1, 1, 0, 1, 0, 1, 0} indicating the values {2, 3, 5, 7} are prime and {0, 1, 4, 6, 8} are not prime.

Example:

W1: 0..8

W2: W1[find(isprime(W1))]

W2 contains the series {2, 3, 5, 7}, the prime values of W1.

Remarks:

A prime number is a natural number (positive integer) with exactly two divisors, 1 and itself. Thus, 0 and 1 are not prime.

See Also:

FACTORS

PRIMES