Mean of a subset of columns for every row

I know there are several question like this, but i want my code be more dinamic and work for every input matrix.

So the problems is this: I have a matrix 34X3000, and I want tho get the mean of 10 columns for every row. The output will be 34x300.

So far I had this, I know the error is for the index but I don't no how to do it. Can you help me?

TotalRecordingTimeSec=length(Data);
binsize=10;%Entrada
timeline=0:binsize:TotalRecordingTimeSec;
AllcelsFR=[];
AllFR=[];
for bb=1:size(Data,1)
 for cc=1:size(timeline,2)-1
    fh=timeline(cc);
    th=timeline(cc+1);
    BinData=Data(Data>fh & Data<th);
    AllFR=[AllFR;nanmedian(BinData)];
 end
AllcelsFR=[AllcelsFR AllFR];
end

Answer 1

[dpb]

N=10;
M=reshape(mean(reshape(Data.',N,[])),size(Data,2)/N,[]).';

[Perla González Pereyra]

This work pretty well, thank you so much. I have to read reshape again

[dpb]

Utilizes that memory storage order in MATLAB is row major and builtin functions such as mean are vectorized to operate by column.

Start with a very small sample dataset like 3x12 or so with N=4, say, that you can verify results by inspection. Then observe each step sequentially at the command line.

(VERY powerful technique)