I am writing a code that will check two numbers whether they are relatively prime or not if they are it would return 1 else 00the problem is that i am getting 1 all the times. Kindly help me midfy my code.

function [r]=prime(a,b)

a=input('Enter 1st number=');

b=input('Enter 2nd number=');

% factors for 1st number

K=1:a;

D1 = K(rem(a,K)==0)

% factors for 2nd number

K=1:b;

D2 = K(rem(b,K)==0)

n1=length(D1);

n2=length(D2);

for i=2:n1

      for o=2:n2

              if (D1(i)==D2(o))

              r=0;

              break

              else

                  if (D1(i)~=D2(o))

                          r=1;

                      end

      end

end

end

[MUTHUKUMAR SETHURAM]

NumbersRange = 47 : 97;
Prime_Index = isprime(NumbersRange);
NumbersRange(Prime_Index)

[Divya]

please share output

Answer 1

[Walter Roberson]

You have a break within a double-nested for loop. That break is only going to break from the inner for loop: you keep running the outer for loop. As long as at least one place a 1 is assigned, then the only thing that has any effect on the output is the last iteration of the outer for loop, because you keep running the outer loop after the inner break.

Your code has another bug, by the way: 1 will divide all values, and when you compare the ones from both sides you say "No, not relatively prime"

Your code is quite inefficient. You should consider using intersect() or ismember()

[Arslan Ahmad]

can you modify my code bcuz I am stuck. I would be grateful if you help

[Walter Roberson]

Minimal modification (rather than "good code")

r = 1;
for i=2:n1

        for o=2:n2

                if (D1(i)==D2(o))

                r=0;

                break

                else

                    if (D1(i)~=D2(o))

                            r=1;

                        end

        end

        if r == 0
           break
        end

end

[Arslan Ahmad]

thanks a lot dear really I am grateful

Answer 2

[Robert]

Just do

r=gcd(a,b)==1

instead