loops - merging and manupulating files in matlab -

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is there way run loop through folder , process 30 files month , give average,max of each columns , write in 1 excel sheet or so??

i have 30 files of size [43200 x 30]
ran different matlab scrip generate them names easy file_2010_04_01.xls , file_2010_04_02.xls ..... , on cannot merge them each 20mbs , matlab crash. ideas? thanks

you can first list of files using function dir. here's example:

dirdata = dir('file_2010_04_*.xls');  %# match file names wildcard datafiles = {dirdata.name};           %# file names in cell array

once have these files, can loop on them using xlsread load data. note xlsread can return different versions of data in excel file:

[numdata,txtdata,rawdata] = xlsread(filename);  %# filename string

here, numdata contains cells numeric data in file, txtdata contains cells text data in file, , rawdata cell array contains of data in file. have determine data array use , how index 43200-by-30 matrix of data process.

putting together, here's code sample how process data column maxima , column averages across of files:

columntotal = zeroes(1,30);             %# initialize column sum columnmax = -inf(1,30);                 %# initialize column maxima dirdata = dir('file_2010_04_*.xls');    %# match file names in current folder datafiles = {dirdata.name};             %# file names in cell array nfiles = numel(datafiles);              %# number of files ifile = 1:nfiles                    %# loop on files   numdata = xlsread(datafiles{ifile});  %# load data   %# here, i'm assuming "numdata" contains 43200-by-30 matrix   columntotal = columntotal+sum(numdata);     %# add column data   columnmax = max(columnmax,max(numdata));    %# column maxima end columnaverage = columntotal./(nfiles*43200);  %# average across files

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