Is it possible to assign the constant value of a function handle to a variable?

Hello,

My program can sometimes generate this function handle:

g = @() 1.0

Or generally: g = @() c , c: constant

Is it possible to transfer that constant into a variable B, so that B = c?

Thanks.

Edit: Is it possible to check whether a function_handle has no inputs(@())?

Answer 1

[Star Strider]

If you want to use the feval (link) function, yes:

g = @() 1;
B = feval(g)

producing:

B =
     1

There may also be other ways to evaluate a function that does not accept an argument.

[Panagiotis Panagopoulos Papageorgiou]

It works, thank you :)

By the way, is it possible to check if the space between the parentheses of a function handle(@()) is blank with an if statement?

[Star Strider]

As always, my pleasure!

I doubt it. When I tried:

g = @() 1;
B = g()

this also worked, producing:

B =
     1

however, this:

     B = g(1)

produced:

     Too many input arguments.

So perhaps you could use a try,catch (link) block to detect those.

Answer 2

[Guillaume]

You don't need to use feval to invoke a function handle with no inputs, just use some empty brackets to make it clear you want to call it and not just copy the handle:

f = @() 0.5;
n = f()

To know the number of inputs of any functions (not just function handles), use nargin:

f = @() 0.5;
g = @(x) x;

>> nargin(f)
ans =
     0
>> nargin(g)
ans =
     1