GUI Text box

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Zach on 18 May 2011
In my GUI I have a text box where the input looks like x(n)=5*rand(1,1)+x(n); , In my m-file code I get the written statement from the textbox by writing eval(get(handles.textbox,'string')); . Is there a way that the input to my textbox will only be 5*rand(1,1)+x(n); and in my m-file I have x(n)=(something to call the string from textbox). I tired x(n)=eval(get(handles.textbox,'string')); and it does not work.
Let me know if I'm not being clear.
  1 Comment
Andy on 18 May 2011
Could you be more clear about what doesn't work? Is there an error? If so, post the message. Does it give unexpected output? If so, post the output and tell us the expected output.

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Accepted Answer

Matt Fig
Matt Fig on 18 May 2011
S = get(handles.textbox,'string'); % S = 'x(n)=5*rand(1,1)+x(n)'
S = S(6:end)
x(n) = eval(S)
Or, more generally,
S = get(handles.textbox,'string'); % S = 'x(n)=5*rand(1,1)+x(n)'
S = regexprep(S,'(?==)','');
x(n) = eval(S)
This takes away everything up to and including the equals sign.

More Answers (1)

Andy on 18 May 2011
Well, I suppose you could do something like
eval(['x(n)=' get(...)]);
Or you could use evalin:
doc evalin
But eval is pretty dangerous. You're letting your user execute arbitrary code.


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