How to break loop if number repeats -Matlab

Question

I recognized this is a quite hard problem for me. I asked this problem on official Matlab side but no-one could help me either so maybe someone of you can come up with an outstanding approach.

In detail my Problem consist of:

N = 100 %some number
G = 21  %random guess < N

for x = 1:N;
a = mod(G^x,N);
end

Now I want the calculation of a to stop, if a number repeats.

For example: a = 1, 2, 3, 1 -break

Seems simple but I just can't handle it right after many tries.

For instance I've put:

for x = 1:N
    a = mod(G^x,N);
    b = unique(a);
    if a ~= b
        break 
    end 
end

but doesn't seem to work bc. it's not element wise I guess.

Cris Luengo · Accepted Answer · 2023-03-30 19:17:38Z

2

This approach keeps a running log of the past Results and uses the ismember() function to check if the current value of a has been previously seen.

clc;
N = 100; %some number
G = 21;  %random guess < N

Results = NaN(1,N);
for x = 1:N
  a = mod(G^x,N);
  disp(a);
  if ismember(a,Results)
    disp("-break");
    break
  end
  Results(x) = a;
end

Ran using MATLAB R2019b

edited Mar 30, 2023 at 19:17

Cris Luengo

61.4k10 gold badges75 silver badges135 bronze badges

answered Jan 24, 2021 at 16:25

Placeholder

4,7672 gold badges8 silver badges23 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

How to break loop if number repeats -Matlab

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related