Prime number generator using gmpy2 producing error

Question

I'm trying to test a function in Jupyter Notebooks that uses gmpy2 to produce prime numbers but I'm getting the following output.

import gmpy2
def solution(i):
    n = 2
    while True:
        yield n
        n = str(gmpy2.next_prime(n))

for i in solution(1):
    print(i)
    input()

2

3

---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-14-e0db74781d33> in <module>
      6         n = str(gmpy2.next_prime(n))
      7 
----> 8 for i in solution(1):
      9     print(i)
     10     input()

<ipython-input-14-e0db74781d33> in solution(i)
      4     while True:
      5         yield n
----> 6         n = str(gmpy2.next_prime(n))
      7 
      8 for i in solution(1):

TypeError: next_prime() requires 'mpz' argument

Why does the function successfully output the first two numbers in the sequence (2 and 3) but then produce an error? What does mpz mean?

There was an question as same before, I think it will help you - https://stackoverflow.com/questions/13326673/is-there-a-python-library-to-list-primes — Lakshan Costa, Nov 19 '20 at 04:04

score 1 · Answer 1 · edited Dec 26 '21 at 21:46

1

In n = str(gmpy2.next_prime(n)) you are changing n to string. That's why it yields 2 and 3, where 2 is an integer, 3 is a string, but gmpy2.next_prime(n) requires an integer.

edited Dec 26 '21 at 21:46

cigien

57,834
11
73
112

answered Dec 26 '21 at 19:12

heressy

11
1

Brahim Bendali · Answer 2 · 2020-11-19T04:18:13.360

-2

import gmpy2
def solution():
    n = 2
    while True:
        yield n
        n = str(gmpy2.next_prime(n))

while True:
    print(solution())

try this way

edited Nov 19 '20 at 04:18

answered Nov 19 '20 at 04:04

Brahim Bendali

1
1

This doesn't print anything out – Nasrat Takoor Nov 19 '20 at 12:01

Prime number generator using gmpy2 producing error

2 Answers2