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Flip a vector using for

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The Canary Cry
The Canary Cry on 15 Mar 2018
Edited: Andrei Bobrov on 15 Mar 2018
I'm a MATLAB beginner in need of some help. I need to flip a vector so that it goes in reverse. Basically, [1 2 3] becomes [3 2 1]; Here's what I've got:
vector=[1:12]
A=0;
j=12;
for i=1:12
A=vector(i);
vector(i)=vector(j);
vector(j)=A;
j=j-1;
end
vector
I'm not really sure why it's not working since this seems like the logical way to do it.

Answers (2)

Andrei Bobrov
Andrei Bobrov on 15 Mar 2018
Edited: Andrei Bobrov on 15 Mar 2018
out = flip(yourvector);
with loop (no use)
out = zeros(size(yourvector));
k = 1;
for ii = numel(yourvector):-1:1
out(k) = yourvector(ii);
k = k + 1;
end
  1 Comment
The Canary Cry
The Canary Cry on 15 Mar 2018
Yes, I know there a functions to do it for me but I need to do it using for.

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James Tursa
James Tursa on 15 Mar 2018
Edited: James Tursa on 15 Mar 2018
Because you are exchanging elements, you wind up flipping the vector twice, which gets it back to the original state. Instead, just run your for-loop through 1/2 of the vector so that the elements are only flipped once. E.g.,
for i=1:floor(numel(vector)/2)
  1 Comment
The Canary Cry
The Canary Cry on 15 Mar 2018
Oh! Yes, I see where I went wrong, thank you.

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