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+--- Thread: Prime number Python homework (/thread-17948.html)
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Prime number Python homework - mkrisz98 - Apr-30-2019
Hi, I got a homework and I have to ask for some help.
My task is:
Listing the first six prime numbers, we get 2, 3, 5, 7, 11, and 13, where 13 is prime number 6. Write a program that defines the prime number N. Create an effective implementation that can calculate 10,000 prime numbers in real time.
Please somebody help me.
Thanks!
RE: Prime number Python homework - Larz60+ - Apr-30-2019
Please show what you have tried so far.
We're here to help, but not do the work for you.
RE: Prime number Python homework - mkrisz98 - May-02-2019
My recent program can only list the prime numbers in an interval.
number = int(input("How many prime numbers do you want ? "))
cnt = 0
for i in range (1, number+1):
for j in range(1, i+1):
if(i%j == 0):
cnt += 1
if(cnt == 2):
print(i)
cnt = 0
RE: Prime number Python homework - DeaD_EyE - May-02-2019
Write a function, which checks a number, if it's a prime.
In another function you collect primes, until you have the number of primes you want to have.
from itertools import count
def is_prime(number):
"""Your implementation"""
return True
def get_primes(n):
primes = []
while len(primes) < n:
for number in count():
if is_prime(number):
primes.append(number)
return primesThe function to check the prime can also taken from other libraries.If you make the easiest implementation, it takes more time to check primes.
RE: Prime number Python homework - mkrisz98 - May-09-2019
I wrote this code, but i don't know why is it exit with exit code 0.
from itertools import count
def is_prime(number):
if number <= 1:
return False
for i in range(2, number):
if number % i == 0:
return False;
return True
def get_primes(n):
primes = []
while len(primes) < n:
for number in count():
if is_prime(number):
primes.append(number)
return primes
RE: Prime number Python homework - mkrisz98 - May-10-2019
Okay, I realized I didn't printed it last time, but if I print it like this, it is just running and running and never stops.
Can you help me what did I wrong?
from itertools import count
def is_prime(number):
if number <= 1:
return False
for i in range(2, number):
if number % i == 0:
return False;
return True
def get_primes(n):
primes = []
while len(primes) < n:
for number in count():
if is_prime(number):
primes.append(number)
return primes
print(get_primes(1))
RE: Prime number Python homework - Yoriz - May-10-2019
from itertools import count will keep returning values forever.for number in count(): has no way of endingwhile len(primes) < n: only happens onceThe following code Removes the while loop and gives the for loop a way out.
from itertools import count
def is_prime(number):
if number <= 1:
return False
for i in range(2, number):
if number % i == 0:
return False;
return True
def get_primes(n):
primes = []
for number in count():
if is_prime(number):
primes.append(number)
if len(primes) == n:
return primes
print(get_primes(1))Output:[2]RE: Prime number Python homework - mkrisz98 - May-10-2019
Thank you so much, this is exactly what i was whinking for!
RE: Prime number Python homework - Yoriz - May-10-2019
Can be improved as it only needs to check len of found primes after appending a new prime, no need to check otherwise.
from itertools import count
def is_prime(number):
if number <= 1:
return False
for i in range(2, number):
if number % i == 0:
return False;
return True
def get_primes(n):
primes = []
for number in count():
if is_prime(number):
primes.append(number)
if len(primes) == n:
return primes
print(get_primes(6))Output:[2, 3, 5, 7, 11, 13]More efficient a second count to keep count
from itertools import count
def is_prime(number):
if number <= 1:
return False
for i in range(2, number):
if number % i == 0:
return False;
return True
def get_primes(n):
primes = []
qty_found = count(1)
for number in count():
if is_prime(number):
primes.append(number)
if next(qty_found) == n:
return primes
print(get_primes(6))Output:[2, 3, 5, 7, 11, 13]RE: Prime number Python homework - mkrisz98 - May-10-2019
Yes it is better. My task is to list 10,000 prime numbers in real time, this code can list it in 30 seconds,
but i think it's real time and enough for me.