Save FOR loop data into a vector

Dear all,

I am trying to save the data that I get from a FOR loop into a vector. Here is my example:

X = [  -5  1 -2  9  100  -3 ]

for i = X(1:1:end)
    if find(0<i & i<10) == 1
     Y = i
    else Y = NaN
    end
end

The above code returns the values after each iteration, separately. I would like them placed into a vector. Could anyone give me a hint on that?

Answer 1

[Iain]

You need your for loop to index into X, rather than use X as the index.

 for j = 1:numel(X)
  i = X(j);
  your code as normal...
  output(j) = Y;
 end

[Agent Cooper]

Thank you very much, Iain. It works just fine now.

Answer 2

[Jos (10584)]

Note that you can loop over elements

X = [1 3 5 2 3 4 1]
Y = zeros(size(X)) ; % pre-allocation makes loops faster
k = 0 ;
for xval = X
   k = k + 1 ;
   disp(xval)
   if xval > 2
      Y(k) = 1 ;
   end     
end

But … matlab can handle vectors/arrays at once, making this much easier!

Y = double(X>2) % X>2 would return a logical array.

[Agent Cooper]

Thank you very much for your answer, Jos.