Passing a constant function handle to another function

I want to pass a constant function handle "simulate" to a function "fftest", so that the corresponding function in the function handle simulate is called during evaluation "fftest" with the provided arguments:

simulate = @depsim;
g = @(x,y) fftest(x,y,@simulate);
g(1,1);

% in separate files:

function ret = depsim(a,b) 
ret = ones(a,b);
end

function  fftest(a,b,simulate)
disp(simulate(a,b));
disp("it works!");
end

I get the following exception, when I run the code:

Not enough input arguments.

Error in depsim (line 3)

ret = ones(a,b)

Error in test (line 28)

simulate = depsim;

I do not understand what the problem is, do I need to pass the handle differently?

Answer 1

[Steven Lord]

What appears in the error message is not what appears in the code you posted. First a comment about the code you posted:

simulate = @depsim;
g = @(x,y) fftest(x,y,@simulate);

As written this is probably not going to work. The first line defines a variable named simulate that contains a function handle. The second line treats simulate as a function and creates a function handle to it. If you wanted to pass the variable you created on the first line into fftest get rid of the second @ in the second line.

simulate = @depsim;
g = @(x,y) fftest(x,y,simulate);

Now from the error message:

Error in test (line 28)
simulate = depsim;

This does not have anything to do with function handles. This attempts to call the depsim function with 0 inputs and assign 1 output from that function call to the variable simulate. If you intended this to create a function handle to depsim, you need the @ before the function name.

simulate = @depsim;

[Leo S]

Sy this is my fault, that was the output of an earlier execution.

Thank you, the second @ at simulate was the problem.