I am trying to make a simple function to sum the prime numbers of a given input. I am wondering why '7' isn't coming up in my appended list of prime numberS:

def sum_primes(n):
    empty = []
    for i in range(2,n):
        if n % i == 0:
            empty.append(i)
    print(empty)

sum_primes(10)

CodePudding user response：

Your method for determining if numbers are prime is a bit off. Your function seems to determine if the input num n is prime but not sum all prime numbers to it.

You could make an isprime function and then loop over that for all numbers less than n to find all primes.

CodePudding user response：

Actually your program have logical error. First you have to understand the prime number logic.

Step 1: We must iterate through each number up to the specified number in order to get the sum of prime numbers up to N.

Step 2: Next, we determine whether the given integer is a prime or not. If it is a prime number, we can add it and keep it in a temporary variable.

Step 3: Now that the outer loop has finished, we can print the temporary variable to obtain the total of primes.

sum = 0
for number in range(2, Last_number   1):
    i = 2
    for i in range(2, number):
        if (int(number % i) == 0):
            i = number
            break;
    if i is not number:
        sum = sum   number

print(sum)