MATLAB: Write a function ShowPrimes(n) that will find all prime numbers between 1 and n and return them as a vector. Do this using a for loop. Hint: use isprime(x) to check whether x is a prime number. As an example, >> primes=ShowPrimes(20) primes =

Question

I'm having some issues with this problem. So far, I have written:

function vec=ShowPrimes(n)

%Creates a vector of all of the prime numbers in a range of 1 to n

%Format:ShowPrimes(n)

for i=1:n

vec(i)=isprime(i);

end

end

This gives me a logical vector, but I need a vector of all the prime numbers. How should I go about fixing my function?

Answer 1

Hello,

The idea is that you use isprime to check is this prime or not.

Then, if it is the prime, you store the value of "i" (not isprime(i)) to the output.