Finds every prime number less than or equal to a given number. Uses is_prime() from U08_Ex05_isPrime.py

U08_Ex06_Primes.py

# U08_Ex06_Primes.py
#
#  Author: Bill Montana
#  Course: Coding for OOP
# Section: A3
#    Date: 22 Nov 2017
#     IDE: PyCharm Community Edition
#
# Assignment Info
#   Exercise: 6
#     Source: Python Programming
#    Chapter: 8
#
# Program Description
#   Finds every prime number less than or equal to a given number.
#   Uses is_prime() from U08_Ex05_isPrime.py
#
# Algorithm (pseudocode)
#   introduce program
#   get integer number from user
#   loop from 2 to given number
#       call is_prime() to test for primeness
#       if prime, print


from U08_Ex05_isPrime import is_prime

def main1():
    # introduce program
    print('This program prints all prime numbers up to a given number.\n')

    # get integer number from user
    num = int(input('Enter an integer: '))

    # loop from 2 to given number
    thisNum = 2
    print('Primes: ', end='')
    firstTime = True
    while thisNum <= num:
        # call is_prime() to test for primeness
        # if prime, print
        if is_prime(thisNum):
            if firstTime:
                print('{}'.format(thisNum), end='')
                firstTime = False
            else:
                print(', {}'.format(thisNum), end='')
        thisNum += 1
    print()

def primes_list(num):
    # int num is argument

    # loop from 2 to given number
    thisNum = 2
    primes = []
    while thisNum <= num:
        # call is_prime() to test for primeness
        # if prime, add to primes
        if is_prime(thisNum):
            primes.append(thisNum)
        thisNum += 1
    return primes

def main2():
    # introduce program
    print('This program prints all prime numbers up to a given number.\n')

    # get integer number from user
    num = int(input('Enter an integer: '))

    # call primes_list(), setting return value to primes[]
    primes = primes_list(num)

    # print list returned by prime_list()
    print('Primes: ', end='')

    for prime in primes:
        print('{} '.format(prime), end='')
    print()

if __name__ == '__main__':
    main2()