Adding filename inside table excel and merge

I don't know it is possible, but I don't remember.

I have several excel (.xslx) almost 3000 file. I would like to insert filename inside table adding one column.

I put one example, these are file excel:

'filename1.xlsx'

'filename2.xlsx'

'filename3.xlsx'

'filename4.xlsx'

'filename5.xlsx'

'filename6.xlsx'

'.....xlsx'

Each excel file has two variables (data and rainfall). for example 'filename1.xlsx':

filename1.data

filename1.rainfall

I would like to put another variable (column) with the filename, in this case is filename1

filename1.data

filename1.rainfall

filename1.filename1

help me!

Maybe using "for"? I don't know

And then it is possible to merge all excel file creating one master excel file?

[Sudharsana Iyengar]

See your question is not clear to me. check this.

%-------------------------------------------------------------------------------------------------
myFolder = 'destination file'; % Define your working folder  (have all your xlsx files here)
%-------------------------------------------------------------------------------------------------
if ~isdir(myFolder)
  errorMessage = sprintf('Error: The following folder does not exist:\n%s', myFolder);
  uiwait(warndlg(errorMessage));
  return;
end
%this is if you input a wrong folder
%--------------------------------------------------------------------------------------------------
filePattern = fullfile(myFolder, '*.xlsx');
xlsxFiles = dir(filePattern);
%this will detect all xlsx files in your folder
%--------------------------------------------------------------------------------------------------
for k = 1:length(xlsxFiles)
  baseFileName = xlsxFiles(k).name; 
  fullFileName = fullfile(myFolder, baseFileName);
  %baseFileName is the name of your file, which we will use for extracting
  %data.
  fprintf(1, 'Now reading %s\n', fullFileName);
  %this will say which file its reading
  xlsxData{k} =readtable(fullFileName);
  T=xlsxData{k};
  writetable(T(1:height(T),1:width(T)), 'dummy.csv');
  opts = detectImportOptions('dummy.csv');
  getvaropts(opts,{''}) % your columns names  
  opts.SelectedVariableNames = {''}; % col name seperated by commas
  TT=readtable('dummy.csv',opts);
 TT(:,5)= % something you want to save.
  destination='your location';
  writetable(TT,[destination,baseFileName,'.xlsx']);
  Z = table2array(T(1:height(T),:));
  B=str2double(Z);
 clear TT T
 
 fh = fopen('dummy.csv','w');
 if exist('dummy.csv', 'file')==2
  delete('dummy.csv');
  
  %we are deleting dummy as dummy is being created in current folder, so it
  %will be detected as a csv and the for loop will go on and on. 
  
  
 end

 



end