sliding window and keeping as a vector

I have D-1 data of points 1-500 I would like to slide this data to have 20points in each window and be as a vector [123...20, 21...40 ect] I was trying to do it but it is showing a matrix (20x25) I am new to matlab anyone could help me please?

Answer 1

[Image Analyst]

How about

array2D = reshape(data, [20,25]);

Is that what you meant and want?

[Nessa]

I would like to divide this 500 points into windows where I have first 20 points then another 20 points...and another (stored as a vectors) that I could make other operation on the data later (like what is an average of each bin of this 20 points, medians )

[Sean de Wolski]

So:

median(array2D,2)

Start with something simple, data = 1:6 , and build from there. reshape and transpose (.') will be your friends

[Image Analyst]

Nessa, if you have the Image Processing Toolbox, look at blockproc() which will let you apply some function/operation to a vector or image in "jumps" of 20. I.e. the window slides along in jumps of 20 pixels (or whatever you specify) rather than one element at a time. Though you could also process array2D row by row.

[Nessa]

thank you, what I did is reshape(data,20,[]); and that is showing me is a matrix instead of vector :(

and Ive read online that there is a way of sliding windows data into n-samples and keep it as a vector not as a matrix.

[Image Analyst]

Well you said you were starting with a vector, so what's the problem? It's already a vector. What operation do you want to do? Moving average, moving mean, some custom linear filter, some highly customized set of operations you've encapsulated into a custom function? What?

[Image Analyst]

Nessa's "Answer" moved here:

calculate an average from each 20 points and further 20 points up to 500

[Image Analyst]

Try this:

data = randi(9, 1, 500); % Sample data
array2D = reshape(data, [20, 25]);
means = mean(array2D, 1)

[Nessa]

thank you :)

[Image Analyst]

You're welcome. If we're done, then can you please mark the answer as "Accepted"? Thanks.