Sum every nth row or array

Hello all,

I have an array which is 150x8192 elements. I want to sum every 4th row of this array, making the new array (150/4)x8192. I am running into issue determining the correct code. I have tried some simple nested for loops, but I always seem to get a new array with the same dimensions (150x8192). Thanks for any suggestions!

Answer 1

[Andreas Goser]

If this is your matrix

A=rand(150,8192);

Then this is "every 4th row"

A(1:4:end,:);

I am not 100% sure what you meand about "sum every 4th row" and still you have the same number of columns, but something like

sum(A(1:4:end,:),1)

may be what you need.

Answer 2

[Aubai]

you can try the Stat_n function under:

http://de.mathworks.com/matlabcentral/fileexchange/61218-element-wise-statistics-moving-statistics