10 examples of 'python prime number list' in Python

12
def primes():
13
    yield 2
14
    yield 3
15
16
    for i in itertools.count(start=5, step=2):
17
        if is_prime(i):
18
            yield i

746
def prime_number_factorisation(n):
747
    if n < 2:
748
        return [n]
749
    i = 2
750
    factors = []
751
    while i * i <= n:
752
        if n % i:
753
            i += 1
754
        else:
755
            n //= i
756
            factors.append(i)
757
    if n > 1:
758
        factors.append(n)
759
    return factors

50
def prime_factors(n):
51
    """Lists prime factors of a given natural integer, from greatest to smallest
52
    :param n: Natural integer
53
    :rtype : list of all prime factors of the given natural n
54
    """
55
    i = 2
56
    while i <= sqrt(n):
57
        if n % i == 0:
58
            l = prime_factors(n/i)
59
            l.append(i)
60
            return l
61
        i += 1
62
    return [n]      # n is prime

7
def isPrime(num):
8
    # Returns True if num is a prime number, otherwise False.
9
10
    # Note: Generally, isPrime() is slower than primeSieve().
11
12
    # all numbers less than 2 are not prime
13
    if num < 2:
14
        return False
15
16
    # see if num is divisible by any number up to the square root of num
17
    for i in range(2, int(math.sqrt(num)) + 1):
18
        if num % i == 0:
19
            return False
20
    return True

16
def primeGen(n):
17
    for i in xrange(2, n):
18
        prime = True
19
        if i % 2 == 0 and i != 2:
20
            continue
21
        sqrtp = int(i ** 1 / 2)
22
        for j in xrange(2, sqrtp):
23
            if j % 2 == 0:
24
                continue
25
            if i % j == 0:
26
                prime = False
27
                break
28
        if prime:
29
            yield i

20
def prime(num):
21
    # num is actually a string because input() returns strings. We'll convert it to int
22
    num = int(num)
23
24
    if num < 0:
25
        print("Negative integers can not be prime")
26
        quit()
27
    if num is 1:
28
        print("1 is neither prime nor composite")
29
        # See how I lazily terminated program otherwise it'd forward "None"(default behaviour of python when function
30
        # returns nothing) rather than True or False. Which could mess up the program.
31
        # If we hit this if statement above statement is printed then program exits.
32
        quit()  # Now you don't need to get sys.exit() to exit python has quit to handle the same thing
33
    if num in [2, 3]:
34
        # if given argument is 2 or 3, it is prime. We used list without defining a variable which is perfectly valid
35
        return True
36
    if num % 2 == 0:  # excluding all even numbers except two.
37
        return False
38
    else:
39
        # Here we are starting counter variable from 3 in range. Second argument excludes numbers above one third
40
        # of the given argument. Third argument in range sets steps to take to 2. This makes loop to iterate odds
41
        for x in range(3, int(num/3), 2):
42
            # Checking if argument is divisible by counter. % is modulus operator which returns remainder of division
43
            if num % x == 0:
44
                return False
45
    # It's okay to have more than one return statement when program hits return statement it exits the function.
46
    return True

17
def isprime(no):
18
    if no == 2:
19
        return True
20
    elif no % 2 == 0:
21
        return False
22
    sq = int(math.sqrt(no)) + 1
23
    for i in range(3, sq, 2):
24
        if no % i == 0:
25
            return False
26
    return True

23
def findprimes(start, end):
24
	for i in range(start, end):
25
		if i not in Checked:
26
			Checked.append(i)
27
			if is_prime(i):
28
				Primes.append(i)

7
def prime():
8
    D = {9: 3, 25: 5}
9
    yield 2
10
    yield 3
11
    yield 5
12
    MASK = 1, 0, 1, 1, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0,
13
    MODULOS = frozenset((1, 7, 11, 13, 17, 19, 23, 29))
14
15
    for q in it.compress(
16
            it.islice(it.count(7), 0, None, 2),
17
            it.cycle(MASK)):
18
        p = D.pop(q, None)
19
        if p is None:
20
            D[q * q] = q
21
            yield q
22
        else:
23
            x = q + 2 * p
24
            while x in D or (x % 30) not in MODULOS:
25
                x += 2 * p
26
            D[x] = p

1
def is_prime(n):
2
	if n < 2:
3
		return False
4
5
	i = 2
6
7
	while i * i <= n:
8
		if n % i == 0:
9
			return False
10
11
		i += 1
12
13
	return True