How to save excel files as the curent date? Help

Hello Everyone,

In my programme, I gather information about a set of pictures and then put the information into an excel file with the column headers 'Image', 'Number of Black pixels', 'Time', 'Status', 'Date'. This all works fine and the data gets saved correctly using xlswrite. However, I want to make a system where my programme creates a folder named with the current month (e.g "August") which I can do with mkdir maybe? Then, I want my MatLab programme to search my computer. If there is a folder with the current month then save the excel file into that folder. I want all excel files done within the same month to be on one spreadsheet but as different 'sheets'? How can I call these sheets by the date and time? (dd/mm/yyyy hh.mm.ss???) Furthermore, if my computer doesn't contain a folder with the current month and year, I want matlab to create one and save all the excel files for that month in there?

Can somebody please help? The basic help I need is how to incorporate the 'date(now)' or 'datevec' syntax's into the xlxwrite syntax?

Here is the current segment of code I use:

PhotoDetails={fullFileName, black, time, Status, Date};    %Date variable here will save the exact time and date the images were processed in answer to line 228 and 234.
    Matrix(k,:)=PhotoDetails;                       %Matrix of three variables produced.
    guidata(hObject,handles);

end
end

mkdir('c:\\AHT Results');

   Header={'Image', 'Number of Black Pixels', 'Time (Seconds)', 'Status', 'Date'};  %Headers that will appear in adjacent cells on excel spread. 
      xlswrite((['c:\\AHT Results', date]), Header, num2str(date));
      xlRange='A2';
      xlswrite((['c:\\AHT Results', date]), Matrix, num2str(date), xlRange); %%Edit 'results' to current date function including seconds so it saves as new tab in monthly workbook.

This returns the error: Error using xlswrite (line 219)

Error in GUI_3_Beta>pushbutton4_Callback (line 280) xlswrite((['c:\\AHT Results', date]), Header, num2str(date));

Error in gui_mainfcn (line 95) feval(varargin{:});

Error in GUI_3_Beta (line 42) gui_mainfcn(gui_State, varargin{:});

Error in matlab.graphics.internal.figfile.FigFile/read>@(hObject,eventdata)GUI_3_Beta('pushbutton4_Callback',hObject,eventdata,guidata(hObject))

Error while evaluating UIControl Callback

Many thanks ,

Ellis

Answer 1

[Geoff Hayes]

Ellis - it isn't all that clear what the xlswrite error might be, but you could consider building your file name with fullfile to ensure that it is valid as

 myDir  = 'C:\\AHT Results';
 myFile = [date '.xlsx'];
 pathAndFilename = fullfile(myDir,myFile);

 xlswrite(pathAndFilename,...);

I'm not sure if that will fix the problem but hopefully any subsequent errors will be more descriptive.

Also, use datestr to format the current date and time. For example,

 datestr(now,'yyyy-mm-dd_HH:MM:SS')

returns

 '2016-08-18_11:57:55'

[Guillaume]

I suspect the problem is with the sheet name. Certainly, it's not possible to use a dd/mm/yyyy hh.mm.ss format for sheet names since / is forbidden by excel.

Geoff's proposed format would not work either. : is also forbidden.

Other forbidden characters are \, *, [, ], and ?. For some reason, the string History is also not allowed.

[Geoff Hayes]

Hmmm...sheet name in this case is just

 num2str(date)

which for me returns

 18-Aug-2016

Is this different based on OS or MATLAB version? (I'm using OS X 10.11.6 and R2014a.)

[Guillaume]

No, the date function is guaranteed (according to the doc) to return the date in the format day-month-year, but I assumed that date is actually a variable shadowing the function. Otherwise, there's no need for num2str.

[Geoff Hayes]

Good point!