Counted Function (CountedFunction)

Class to define functions in a way that facilitates counting the number of function calls/evaluations.

CountedFunction

Class to define functions in a way that facilitates counting the number of function calls/evaluations.

Usage

[fc,count] = CountedFunction.count_function_calls(f)

Description

[fc,count] = CountedFunction.count_function_calls(f) takes a function handle, f, and returns a function handle fc and a counter function count. fc performs the same function evaluation as f (it is just wrapped around a CountedFunction object which calls f directly). Calling the counter function (i.e. count()) will return the current number of function calls.

Note

• For simple functions, such as f = @(x) x^2, this can severely slow down function calls (by a factor of ~20).
• For complicated functions that have a long evaluation time to begin with, this performance hit is negligible.

Basic Example

See more examples in Examples.mlx.

% define the function
f = @(x) x^2;

% new function handle that counts the number of function evaluations
[f,count] = CountedFunction.count_function_calls(f);

% evaluates the function 1000 times
for i = 1:1000
    f(0);
end

% prints the number of function evaluations
count()

ans =

        1000

% evaluates the function another 1000 times
for i = 1:1000
    f(0);
end

% prints the number of function evaluations again
count()

ans =

        2000