Thanks for posting this great utility! Seeing your question dialog and looking through the code, I saw your use of the function “setpref.” I didn’t know about this very useful function, so thanks for that too!

Hi, thanks for inspirational blog spot. Have you got any idea if it is possible to save TC.xml to any other location, where the Matlab path is set? It can be useful in case that I have not permission to modify TC.xml in [matlabroot ‘/toolbox/local/’] folder, or if I distribute own toolbox and can’t modify default TC.xml:).
BTW thank you for link.
Best Michal

@Michal – unfortunately, I don’t know of any other possible location. As far as I know, Matlab directly opens [matlabroot ‘/toolbox/local/TC.xml’]. We can’t win ’em all…

In your toolbox, try modifying TC.xml, with a graceful degradation in case this fails. Something like this:

try
   tabcomplete(...);
catch
   oldFname = fullfile(matlabroot, 'toolbox/local/TC.xml');
   newFname = fullfile(pwd,'TC.xml');
   msgbox(['Please ask your sysadmin to replace ' oldFname ' with ' newFname]);
end

A related question, which however is not tab completion, but presents informaiton is the same way:

When in the workspace I type e.g. “plot(” or “corrcoef(” and wait a second, I am presented with a context sensitive help showing a number of ways to use the “plot” or “corrcoef” functions. Where is this context sensitive help stored? I have tried to look at different functions to see how the help-section is written, and made a similar setup:

function testHelp(x,varargin)
% TESTHELP   See how context help is defined
%   TESTHELP(X)
%
%   TESTHELP(X,Y)

but it does not present me with a “similar” context sensitive help…

Cheers Henrik

@Henrik – I believe the syntax help is taken from the “Syntax” section of the relevant function’s doc page (the HTML webpage that is presented as a result of the doc function).

If no doc page is defined, then the help-tooltip popup displays the arguments defined in your function’s declaration. In your example, testHelp is declared as having arguments “x” and “varargin”. “varargin” is always converted to “…”, so your tooltip will say: testHelp(x,…). If you wish to modify this, then specify meaningful argument names (which is always a good thing to do), and/or ^[15].

I tried to implement on R2013a a custom doc page but couldn’t get the desired result. Even if the section is title ‘Syntax’, I still get the ‘…’ as a hint. If anybody finds a workaround please post it and in the meantime submit a request to TMW for custom syntax hints. Hopefully, with enough requests we will see it in R2013b.

@Oleg – 13b is too optimistic… The development process is such that releases are finalized months before their official release. At the very earliest you will see it in 14a.

is it possible to perform autocomplete in matlab without using funtionality just like we type in google search bar

@Akash – what do you mean “in Matlab”? Do you mean the Command Window? edit boxes in GUI? combo-boxed (pop-up/pop-down menus)? each of them has a different solution

[…] check the <Tab key narrows completion> option (most useful for the desktop – see related article) […]

This is only tangentially related… but I’m hoping there is an undocumented way to change the fact that Matlab Tab completes case-insensitively but doesn’t auto-replace the name when it finds the wrong case. This results in tab-completions to functions that error.

@Marshall – I fully agree. Indeed a regrettable programming oversight. Unfortunately, I do not know any workaround.

Great post as always!

I modified TC.xsd file (r2013a) from:

to

In order to allow full package names to be added on TC.xml

Now the problem is that if I try to call a package level function as a script, somehow Matlab wont let me. In otherwords on the prompt:

myPackage.myFunction('str')

works fine, but:

myPackage.myFunction str

doesn’t. Is there a reason that packaged functions might not be supporting script-like calling?

@Marios – your comment appears without the code, maybe it was stripped away for some reason. Try reposting without <, > characters

Sure, here are the lines again. In TC.xsd I changed:

to:

So that by adding a packaged function name on the TC.xml such as:

I can have auto-completion on the prompt. So on the prompt, when I type:
>> myP<tab>.myF<tab><space>myF<tab>
I can now autocomplete myF to myFile but some how Matlab doesn’t push the string literal myFile as an argument to myPack.myFun but instead gives an error:

Error: Unexpected MATLAB expression. 

Of course if I call myPack.myFun(‘myFile’) it works fine. My conclusion is that command-syntax doesn’t work with packaged functions but of course function syntax does.

I opened a ticket with Mathworks support but they said this functionality is not supported at this point. My general feeling is that packages are pretty half baked at this point. (also Ctrl-D on imported functions doesn’t work etc.)

@Marios – interesting. Since the tab-completion thing is internal (as in binary code, not m-code), there’s not much that we can do about this…

Right, there is not much we can do according to Mathworks support as well.

My partial solution is to create function aliases on a flat namespace when I absolutely need tab-completions on the desktop.

Hi very nice. I try to do the same for custom class definitions. For the constructor it’s straight forward but I didn’t find any solutions for methods. I tried something like:

(All with a smaller-as sign at the beginning but, if I print those the text is disappearing…)

But all it did is break TC. You mentioned something about a solution for custom classes but the link doesn’t seem to work. Could you elaborate a little bit more how this works?

@Marc – “ClassName” is not one of the acceptable ctype enumerations, explaining why your TC broke. You need to use “MCOSPKG” and/or “MCOSCLASS” to signify that the first arg needs to be a class object.

To limit the binding to a specific class, you could try the syntax in Marios’ comment above:

(you’d need to modify xsd:pattern to include the . character, as shown in Marios’ comment)

Hi

Great article. Can this method also be used for classes?
For the constructor it’s rather simple following your procedure. But I did fail to do so for class methods. I did post this question also on Stackoverflow ( ^[16]). Feel free to answer also there if you like and earn your credit.

@Magu – try to implement hidden methods fieldnames and/or methods in your class. The first is for properties, the second is for methods.

Thank you for your answer.

This is very neat I didn’t know that exist. I did it for the fieldnames but failed for methods so far.

“methods” seems to behave differently depending on nargout. Zero output should not matter in this case single output gives back names in cell’s and double output the same again as well as some meta-data cell matrix which I don’t understand fully (and searching in google for function methods doesn’t really help^^).

That’s my take so far:

classdef test (smaller_as) < handle
    properties
        s
    end
    methods
        function o = test()
        end
    end
    methods (Hidden)
        function out = fieldnames(o)
            out = {'x1'; 'x2'};
        end
        function [names,meta] = methods(o)
            names = {'y1'; 'y2'};
            meta = {'' '' 'test.test' '' []; ...
                    '' '' 'test.asd' '(A,B)' 'C'};
        end
    end
end

Dear Yair,

I have a related, seemingly-trivial question. I was wondering whether there’s any way to disable tab auto-complete altogether outside of a GUI interface.

I often need to work through a shell mode command line on Unix. If I copy-paste blocks of code from my desktop editor, whenever there is a tab in the original code, I get a “no completions found” output, which sometimes renders the output illegible.

I was not able to find any documentation of discussions on how to do that.

Many Thanks,
Yannay

sorry, I meant that I was UNable to find any documentation OR discussions…

@Yannay – You can disable command-window tab completion via the main Preferences: Keyboard/Shortcuts group – Tab Completion section – “Enable in Command Window” checkbox.

Thank you for responding so quickly—
Let me make myself clearer: I am on the Unix command line and I am not using a GUI. I am trying to find a way to get the same result outside of the GUI platform. Is there any hope?

Yannay – simply add the following line to your matlab.prf file (edit([prefdir,'/matlab.prf'])):

CommandWindowTabCompletion=Bfalse

(remember to restart Matlab in order for the change to take effect)

Discussion: ^[17]

Thanks! I understand now that you previously were indeed referring to command line preferences control, so you did get me right.
I will follow your advise. If it works it would save me infinite irritations…

Unfortunately it doesn’t do what it should. I changed the matlab.prf file as instructed, restarted Matlab, but the “no completions found” feedback still appears following tabs. Is there anything else to try before giving up?

try replacing your tabs with spaces in the editor

Yes, I was aware of this option. I am putting it off right now, and will update here if I find a solution. Many thanks for taking the time and explaining about the off-GUI preferences setting.

Note that tab completion for class properties can also be achieved by subclassing the matlab.System class as I describe in my answer: ^[18]

@Oleg – thanks for the cross-reference

[…] I described the hack for desktop tab-completion a few years ago. Unfortunately, that hack only works for functions. […]

Is it possible to make tab-completion case sensitive with editing the TC.xsd file?

if the functions DOtest.m and dothis.m exist,

I want MaTlab to offer me only DOtest for the case that I enter DO[TAB]

Is this possible?

Hi Yair,

your article saved my fingers for years now, thank you very much!

But with R2016b I cannot find TC.xml anywhere, there seems to be a new solution for tab-completion.

It can be found under “Tab key narrows completions” in the keyboard preferences and is deactivated by default. The entry in matlab.prf can be found under “CommandWindowTabNarrows=Btrue” while “CommandWindowTabCompletion” seems to be removed/replaced.

Do you have any experience with that?

Many thanks in advance!
Tobias

Ok, I’ve just found your “Take 2” about that topic, thanks!