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Here's a question that was recently posed at MathWorks.<\/p>\r\n

I'm trying to invoke a function handle. It either returns 0 or 1 output arguments. If it returns an output\r\n argument, I want to get it; if not I would like to just invoke the function and be on my way. I have no way of knowing ahead\r\n of time whether the function returns something or not. <\/blockquote> <\/html>\r\n <\/p>

 <\/pre>This situation can arise when you are building an application in which you expect to work with user-supplied functions.  You\r\n         can solve this using try<\/tt><\/a> construct, but this situation arises frequently enough that we decided to introduce the nargout<\/tt> bump. So what happens?\r\n      <\/p>\r\n   <\/introduction>\r\n   
Contents<\/h3>\r\n   \r\n      \r\n         nargout Bump from 0 to 1<\/a><\/li>\r\n         
Why does nargout Behave this Way?<\/a><\/li>\r\n         
Will this Simplify Some Code?<\/a><\/li>\r\n      <\/ul>\r\n   <\/div>\r\n   nargout Bump from 0 to 1<\/a><\/h3>\r\n   Many MATLAB functions return 1 result even when called with an nargout<\/tt><\/a> is 0. For these, here's a technique that may be of interest.  It allows for a bump in nargout<\/tt> on the left-hand side.\r\n   <\/p>\r\n   
Let's assume the variable c<\/tt> is unitialized and then call a function f<\/tt>.\r\n   <\/p>
   [c{1:0}] = f(...);<\/pre>f<\/tt> is called with nargout<\/tt> of 0, because 1:0<\/tt> is an empty vector.  If f<\/tt> returns no arguments, c<\/tt> is an empty cell<\/tt><\/a>. However<\/i>, if f<\/tt> returns a result, c<\/tt> is a 1x1 cell containing that result.\r\n   <\/p>\r\n   
Why does nargout Behave this Way?<\/a><\/h3>\r\n   Since this is not a widely known technique, I'll explain one more use of it.  Suppose you are writing a function foo<\/tt>, and after some preparation you want foo<\/tt> to return all of the results, if any, of a call on bar<\/tt>, passing along to bar<\/tt> the number of arguments given to foo<\/tt>.  The template looks like this.\r\n   <\/p>   function varargout = foo(...)\r\n     ... whatever ...\r\n   [varargout{1:nargout}] = bar(...);<\/pre>Anonymous functions use exactly this technique to pass along nargout<\/tt> to their body and to return that body's results as the result of the anonymous function.  This requirement on anonymous functions,\r\n      and the observation that a significant number of other functions work in the same way, is why we introduced the bump.\r\n   <\/p>\r\n   Will this Simplify Some Code?<\/a><\/h3>\r\n   I wonder if this information allows you to simplify some of your code. Please share your results here<\/a>.\r\n   <\/p>