Decrease a size of matrix using interpolation

Good evening everyone,

I have a matrix with 108064 x 2 size. I want to decrease its size to aproximately 2000 using interpolation. Thus, if we consider this matrix as cells and my plan is to see every 64 data like one data with using interpolation and it is going to be around 1600 cells. How can i implement it on Matlab. Thank you. Sincerely...

[John D'Errico]

That is not interpolation, but a downsizing. It sounds like you just want to average every 64 elements, a far different thing than interpolation.

[Ozan Carikci]

Yes i want to take average of every 64 elements, how can i do downsizing on a matrix 108064 x 2 size?

Answer 1

[Mathieu NOE]

hello

demo with a simple for loop :

% dummy data
VectorTime = rand(5000,2);
buffer = 64;    % nb of samples for averaging 

% zero overlap mean averaging
[m,n] = size(VectorTime)

for ci=1:fix(length(VectorTime)/ buffer)
    start_index = 1+(ci-1)*buffer;
    stop_index = min(start_index+ buffer,length(VectorTime));
    time_index(ci) = round((start_index+stop_index)/2);  % time index expressed as sample unit (dt = 1 in this simulation)
    avg_data(ci,:) =mean(VectorTime(start_index:stop_index,:))  % 
end

figure(1),
plot(time_index,avg_data);