Function primeFactorization

primelib/primelib.py:153–188

input: positive integer 'number' returns a list of the prime number factors of 'number'

(number)

def primeFactorization(number):
    """
    input: positive integer 'number'
    returns a list of the prime number factors of 'number'
    """

    # precondition
    assert isinstance(number, int) and number >= 0, "'number' must been an int and >= 0"

    ans = []  # this list will be returns of the function.

    # potential prime number factors.

    factor = 2

    quotient = number

    if number == 0 or number == 1:
        ans.append(number)

    # if 'number' not prime then builds the prime factorization of 'number'
    elif not isPrime(number):
        while quotient != 1:
            if isPrime(factor) and (quotient % factor == 0):
                ans.append(factor)
                quotient /= factor
            else:
                factor += 1

    else:
        ans.append(number)

    # precondition
    assert isinstance(ans, list), "'ans' must been from type list"

    return ans


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