Addition of data from different files using a loop

clear
clc


[files,pathname]=uigetfile('*.hdf','MultiSelect','on');

cd ../../../../../../../../../..
cd(pathname)

files=files';

NumFiles=length(files);
%FMF_S=zeros(31,1);

for m=1:NumFiles
    filename=files(m);
    filename=char(filename);
  data=hdfread(filename,'Ice_Water_Content_Profile'); %reading ice water dataset
lat=hdfread(filename,'Latitude');
lat=double(squeeze(lat(:,1)));
data(data==-9999)=nan; %removing fill value
data(data<0 | data>0.54)=nan; %removing out of range values
% data(data==0)=nan;

data(m,:)=data;
end

say i have three files, a.hdf anf b.hdf and c.hdf, i want the data should be added up in each case , and data matrix dimention remains the same. say for the first file data=846x399 double, when all the three files added up, matrix will remain the samr, i.e, 846x399 double but the three files data shall added up. how to do it with loop? I am getting "Subscripted assignment dimension mismatch." when i use my code,

[Sindar]

data(m,:)=data;

takes all of data, and puts it into the first row of data. So, you're trying to fit an 846x399 matrix in a 1x399 column.