MATLAB Central Newsreader - Syntax checking

Syntax checking

Adam — Sun, 03 May 2009 18:32:01 -0400

Hi all,

I am programming a toolbox and I have the following question:

Does matlab have any built in functions to confirm the correct syntax for a call to ones own function. For example, it would be nice to specify that the function needs either an array followed by a cell array, or, just the string 'all', or two strings where the first one is not 'all', etc...

If matlab had this, then one could easily put all syntax checking up front, and also expect to get nice error messages.

Thank you!
Adam

Re: Syntax checking

Matt Fig — Sun, 03 May 2009 20:23:02 -0400

The closest function that I know of is nargchk. But I don't think it fulfills all your requirements. I always write my own input checking which goes at the head of the function, it is not to hard to do this.

Re: Syntax checking

Jiro Doke — Sun, 03 May 2009 20:49:01 -0400

"Adam " <king@cs.fairfield.edu> wrote in message <gtknv1$mr4$1@fred.mathworks.com>...
> Hi all,
>
> I am programming a toolbox and I have the following question:
>
> Does matlab have any built in functions to confirm the correct syntax for a call to ones own function. For example, it would be nice to specify that the function needs either an array followed by a cell array, or, just the string 'all', or two strings where the first one is not 'all', etc...
>
> If matlab had this, then one could easily put all syntax checking up front, and also expect to get nice error messages.
>
> Thank you!
> Adam

Adam,

If you're using R2007a or newer, you can use the inputParser class:

http://www.mathworks.com/access/helpdesk/help/techdoc/matlab_prog/bresuxt-1.html#bresuxt-11

(note that this is from the current documentation)

NARGCHK will check the number of arguments:

http://www.mathworks.com/access/helpdesk/help/techdoc/ref/nargchk.html

Also, VALIDATEATTRIBUTES and VALIDATESTRING may be useful (R2007b or newer):

http://www.mathworks.com/access/helpdesk/help/techdoc/ref/validateattributes.html
http://www.mathworks.com/access/helpdesk/help/techdoc/ref/validatestring.html

Hope this helps.

jiro

Re: Syntax checking

Adam — Sun, 03 May 2009 21:28:01 -0400

Thank you both. This really helps a lot.

-- Adam