open - Open file in appropriate application

Syntax

Description

open(name) opens the specified file or variable in the appropriate application.

output = open(name) returns an empty output ([]) for most cases. If opening a MAT-file, output is a structure that contains the variables in the file. If opening a figure, output is a handle to that figure.

Tips

The open function opens files based on their extension. You can extend the functionality of open by defining your own file handling function of the form openxxx, where xxx is a file extension. For example, if you create a function openlog, the open function calls openlog to process any files with the .log extension. The open function returns any single output defined by your function.

Input Arguments

st = open(name)

Examples

Open Contents.m in the MATLAB Editor by typing:

open Contents.m

Generally, MATLAB opens matlabroot\toolbox\matlab\general\Contents.m. However, if you have a file called Contents.m in a directory that is before toolbox\matlab\general on the MATLAB path, then open opens that file instead. To change the path, select File > Set Path.

Open a file not on the MATLAB path by including the complete file specification:

open('D:\temp\data.mat')

If the file does not exist, MATLAB displays an error message.

Create a function called opentxt to handle files with extension .txt:

function opentxt(filename)

   fprintf('You have requested file: %s\n', filename);

   wh = which(filename);
   if exist(filename, 'file') == 2
     fprintf('Opening in MATLAB Editor: %s\n', filename);
     edit(filename);
   elseif ~isempty(wh)
     fprintf('Opening in MATLAB Editor: %s\n', wh);
     edit(wh);
   else
     warning('MATLAB:fileNotFound', ...
             'File was not found: %s', filename);
   end

end  

Open the file ngc6543a.txt (a description of ngc6543a.jpg, located in matlabroot\toolbox\matlab\demos):

photo_text = 'ngc6543a.txt';
open(photo_text)

open calls your function with the following syntax:

opentxt(photo_text)

See Also

edit | load | openfig | openvar | path | uiopen | which | winopen