Why is this function handle being used in the incorrect context?

Question

I am trying to understand how to pass functions to varfun, which I suppose applies to arrayfun, cellfun etc.

Reading the helpf

Answer 1

In the first code snippet, mean is a (named) function, and @mean is a function handle to that function. You could equivalently use

f = @mean;
varfun(f, dataTable)

In the second case, when you define

mymean = @(x){sum(x)/length(x)};

the @(x){sum(x)/length(x)}part is an anonymous function, and the variable mymean is again a function handle to that (anonymous) function. So you need to use varfun(mymean, dataTable), not varfun(@mymean, dataTable).

So, the @ sign is being used in two different ways, although in both cases it produces a function handle:

• Case 1: to create a function handle from a named function. A named function is a function that is defined in its own file.
• Case 2: as part of an anonymous function definition. An anonymous function is defined directly, not in a separate file. The definition constructs an anonymous function and automatically returns a handle to that function.