Problem 6. Select every other element of a vector

Thats the question:

Write a function which returns every other element of the vector passed in. That is, it returns the all odd-numbered elements, starting with the first.

Examples:

 Input  x = [1 3 2 4 3 5]
 Output y is [1 2 3]

 Input  x = [5 9 3 2 2 0 -1]
 Output y is [5 3 2 -1]

Thats the code I wrote:

function y = everyOther(x)
y=[];
t=0.5*length(x);
for n=1:t
y=[z x((2*n)-1)]
end

What is wrong with it? Can you help me? :)

Answer 1

[Harald]

Hi Mayla,

one issue I see: you are using z without having previously defined it.

A key point in MATLAB: you do not need to write a loop for this. This can be accomplished by one indexing operation:

y = x(1:2:end);

Best wishes,

Harald

[Mayla]

Thanks a lot Harald! Is there any other basic learning course except Onramp I can do afterwards?

[Harald]

Hi Mayla,

on https://matlabacademy.mathworks.com/, you will find a lot of resources. The Onramps are free for everybody. A lot of universities have an agreement to also make the other offerings available to their students and staff at no extra cost.

The natural next step after MATLAB Onramp will be MATLAB Fundamentals.

If you or other readers prefer to have a live instructor to talk to, there is an instructor-led alternative:

https://www.mathworks.com/learn/training/matlab-fundamentals.html

If the answer helped you, please kindly "accept" it.

Thank you and best wishes,

Harald

Answer 2

[Afsal]

function y = everyOther(x)

y = x(1:2:length(x));

end