How to put the solutions of a equation in a matrix (there are different solutions because variables are changeable), then find the wanted solutions with it's variables?

If this is my equation:

x = 10*a(i) + b(j) ;

a = [1 2 3] ;

b = [ 3 1 6] ;

& I only want to keep the solution if x is greater than 25.

I want to find all the possible solutions of x and find the minimum or maximum x with the variables of that x.

counter = 0;

for i = 1:3

for j = 1:3

counter = counter + 1;

for k = 1: counter

solutions = zeros (1, counter);

x = 10*a(i) + b(j) ;

if x > 25

solutions (k) = x;

else

continue

end

end

end

end

min (solutions);

But how can I find the variables that creates the minimum solution?

There are more variables and complicated conditions in real so I can not calculate by hand.

I hope I was clear, English is not my mother tongue.

Thanks for your time and I wish you health&safety!

Answer 1

[Ameer Hamza]

Try this

a = [1 2 3];
b = [3 1 6];

[A, B] = ndgrid(a, b);

A = A(:);
B = B(:);
x = 10*A + B;

[x_min, idx] = min(x(x>25));

A_sol = A(idx);
B_sol = B(idx);

[Gul Cinar]

Hello Mr.Hamza,

I have edited your answer for the original complex problem and got the results I wanted.

Thank you so much!

Best wishes.

[Ameer Hamza]

I am glad to be of help!