Break a loop when reading different excel files

Dear all,

I am trying to read different excel files from 2010 to 2012. Basically, for each month, there is one excel file. So when i run the loop I go through each month and read the excel file of that particular. The loop works with no problem for 2010 and 2011 but it stops at the end of 2012 because the data for November and December 2012 are not available yet. Here is my code:

months={'Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'};

    for i=2010:2012 

        for j=1:length(months)

 a1=xlsread(['P:\X\Data\', num2str(i),'\', char(months(j)), num2str(i), '.xls'],'Sheet1','X5:X5000');

        end

     end

As you can see the loop reads the excel file at each month but stops at end 2012. I would like to end (break) the loop when Matlab doesnt find the relevant excel file. How can I do that? Thank you very much for your help

Kind REgards

S

Answer 1

[Image Analyst]

It's more robust if you don't break and just check for existence and let it finish the loop. For example, what if all the files are there except the February file? If you broke out, you'd never process the March file or any files in subsequent years. It doesn't take long at all to check filenames for existence. If you want, you could also call warndlg() if there is a missing file. And a1 gets overwritten on each iteration in your loop, so I assume that there's some processing that goes on in the loop that you didn't show.

Try it this way, using braces instead of char(), and using exist(), sprintf(), and fullfile():

months={'Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'};
for theYear = 2010:2012  
  for theMonth=1:length(months)
    baseFileName = sprintf('%s%d.xls',  months{theMonth}, theYear);
    fullFileName = fullfile('P:\X\Data\', num2str(theYear), baseFileName)
    if exist(fullFileName, 'file')
      a1 = xlsread(fullFileName, 'Sheet1', 'X5:X5000');
    end    
  end  
end

[Saad]

Thanks so much! it is working well!