find the sum of all non prime numbers in matlab

main.m
function result = sumOfNonPrimes(upperLimit)
% Returns the sum of all non-prime numbers between 1 and upperLimit

% Helper function to check if a number is prime or not
function isPrime = isPrimeNumber(n)
    isPrime = true;
    for i = 2:sqrt(n)
        if mod(n, i) == 0
            isPrime = false;
            break;
        end
    end
end

% Initialize running sum
totalSum = 0;

% Iterate through all numbers between 1 and upperLimit
for num = 1:upperLimit
    % Check if number is not prime
    if ~isPrimeNumber(num)
        totalSum = totalSum + num;
    end
end

% Return final sum
result = totalSum;
end
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main.m
>> sumOfNonPrimes(10)
ans =
    20
>> sumOfNonPrimes(50)
ans =
    707
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