subdivision of samples to calculate RMS

Hi, I have a signal recorded with 10^6 samples. I would like to calculate its RMS for each 10^2 samples. Could you show me how to do it please ? Thanks

Answer 1

[Wayne King]

You can create a matrix where you take every 100 consecutive samples of your waveform and use those as the columns of the matrix. The you can compute the RMS value for each column.

   x = randn(1e6,1);

   for nn = 0:1e4-1
      X(:,nn+1) = x(nn*100+1:(nn+1)*100,1);
   end

You could also try repmat for this, but you may run into memory problems.

    x = randn(1e6,1);
    x1 = repmat(x,[1e2 1e4]);

The for loop above should not have memory issues.

Answer 2

[Win co]

thanks alot for your answer. It works very well.