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I have this prime factor generator for some number n. It returns list of all prime factors. In other words, product of the list equals n.

def prime_factors_generate(n):
    a = []
    prime_list = sorted(primes())
    pindex = 0
    p = prime_list[pindex]
    num = n
    while p != num:
        if num % p == 0:
            a.append(p)
            num //= p
        else:
            pindex += 1
            p = prime_list[pindex]
    return a

The primes() function uses the Sundaram Sieve from here and returns a set of all primes below some limit, by default 10⁶.

How can I make this code functional? I want to get rid of the while-loop, list appending and mutated state.

I have this prime factor generator for some number n. It returns list of all prime factors. In other words, product of the list equals n.

def prime_factors_generate(n):
    a = []
    prime_list = sorted(primes())
    pindex = 0
    p = prime_list[pindex]
    num = n
    while p != num:
        if num % p == 0:
            a.append(p)
            num //= p
        else:
            pindex += 1
            p = prime_list[pindex]
    return a

The primes() function uses the Sundaram Sieve from here and returns a set of all primes below some limit, by default 10⁶.

How can I make this code functional? I want to get rid of the while-loop, list appending and mutated state.

I have this prime factor generator for some number n. It returns list of all prime factors. In other words, product of the list equals n.

def prime_factors_generate(n):
    a = []
    prime_list = sorted(primes())
    pindex = 0
    p = prime_list[pindex]
    num = n
    while p != num:
        if num % p == 0:
            a.append(p)
            num //= p
        else:
            pindex += 1
            p = prime_list[pindex]
    return a

The primes() function uses Sundaram Sieve from Fastest way to list all primes below N in python @ StackOverflow and returns a set of all primes below some limit, by default 10^6.

How can i make this code functional? I want to get rid of while-loop, list appending and mutated state.

I have this prime factor generator for some number n. It returns list of all prime factors. In other words, product of the list equals n.

def prime_factors_generate(n):
    a = []
    prime_list = sorted(primes())
    pindex = 0
    p = prime_list[pindex]
    num = n
    while p != num:
        if num % p == 0:
            a.append(p)
            num //= p
        else:
            pindex += 1
            p = prime_list[pindex]
    return a

The primes() function uses the Sundaram Sieve from here and returns a set of all primes below some limit, by default 10⁶.

How can I make this code functional? I want to get rid of the while-loop, list appending and mutated state.

I have this prime factor generator for some number n. It returns list of all prime factors. In other words, product of the list equals n.

def prime_factors_generate(n):
    a = []
    prime_list = sorted(primes())
    pindex = 0
    p = prime_list[pindex]
    num = n
    while p != num:
        if num % p == 0:
            a.append(p)
            num //= p
        else:
            pindex += 1
            p = prime_list[pindex]
    return a

How can i make this code functional? I want to get rid of while-loop, list appending and mutated state.

I have this prime factor generator for some number n. It returns list of all prime factors. In other words, product of the list equals n.

def prime_factors_generate(n):
    a = []
    prime_list = sorted(primes())
    pindex = 0
    p = prime_list[pindex]
    num = n
    while p != num:
        if num % p == 0:
            a.append(p)
            num //= p
        else:
            pindex += 1
            p = prime_list[pindex]
    return a

The primes() function uses Sundaram Sieve from Fastest way to list all primes below N in python @ StackOverflow and returns a set of all primes below some limit, by default 10^6.

How can i make this code functional? I want to get rid of while-loop, list appending and mutated state.