find prime numbers between 1 to 100

write a program using nested For loop to determine prime numbers from 1 to 100 in matlab

[David Hill]

Show us what you have done and ask a specific question.

[Sameer Khan]

i need some hint for this program

[DGM]

Did you try this?

https://duckduckgo.com/?q=find+prime+numbers+between+1+to+100

Answer 1

[Walter Roberson]

N = 100;
is_a_prime(1:N) = true;
for k = 3 : N
   for c = 1 : 100
      if mod(k, randi([2 k-1])) == 0
        is_a_prime(k) = false;
        break;
      end
   end
end
find(is_a_prime).'

ans = 29×1

1 2 3 5 7 11 13 17 19 23

[Walter Roberson]

By the way, above result is not guaranteed. And even for what it does it could be improved.

Answer 2

[Jan]

You got a valuable hint already, that nested loops are useful:

for k = 1:100
   for f = 2:100
       % Now check if f is a divider of k
   end
   % If no divider was found, k is a prime
end

Does the innerloop need to run until 100?

[DGM]

I'll add, does k need to include all numbers from 1:100? Is there an obvious pattern of numbers k can skip?