Another approach is to write the set of commands to an m-file that can run as a script or a function and then you can call that script/function from within the GUI. This method allows for evaluation of more complex code than the evalc() approach.
Here's a demo.
Part 1: Create GUI with edit text window and 'Compute' button. The text window will contain some code to be analyzed.
fh = figure();
editBoxHandle = uicontrol('style','edit','units','normalize','position',[.1 .1 .6 .6],'Max',2,...
'String',['x = -pi : 0.001 : pi;', newline, 'y = zeros(size(x));', newline, newline, ...
'for i = 1:numel(x)', newline, ' y(i) = sin(x(i));', newline, 'end'], ...
'HorizontalAlignment','Left');
uicontrol('style','PushButton','units','normalize','position',[.3 .75 .2 .1],...
'String','Compute','Callback',{@mainWindowCommandFcn, editBoxHandle});
Part 2: Define the callback function to the 'Compute' button. The 3rd input is the edit box handle. If you're using GUIDE or APP DESIGNER, you can get this handle through the handles or app structure, respectively. Before running this code, edit the path to the m-file (see mfileName variable).
function mainWindowCommandFcn(hObj,~, editBoxHandle)
commandTxt = editBoxHandle.String;
commandTxt = [commandTxt,repmat(newline,size(commandTxt,1),1)];
mfileName = fullfile('C:\Users\name\Documents\MATLAB','mainWindowCommandFcn.m');
fid = fopen(mfileName,'w+');
if fid<0
error('Error accessing %s',mfileName)
end
fprintf(fid,'%s',sprintf('%s',commandTxt'));
fclose(fid);
if exist(mfileName,'file')~=2
addpath(fileparts(mfileName))
end
run(mfileName);
disp(y)
end
Caveats:
- If the m-file you create is a script, any variable names created by the user in the edit-window will overwrite variable names in your callback function. To decrease the chances of error, use long and strange variable names in your callback function.
- If the user does not suppress outputs using a semicolon, results for those lines will display in the command window. You can easily add semicolons to all lines in order to avoid that.
- If the user's code is not functional, errors/warnings will be thrown from the m-file but the error stack will clearly show that the callback function called the m-file so error tracing shouldn't be too difficult.
- What ever variable you use after evaluating the user's code must exist in the user's code as an exact case-sensitive match.
