为什么需要Matlab函数“feval”？

Question

A function handle can be used to call a function, eg

f = @sin;
val = f(1.0);

so why is feval ever needed?

val = feval(f, 1.0);

When is it useful?

Answer 1

For feval , the first argument can be a quoted string, giving you more flexibility than a function handle. You could do things like having functions with a base name followed by an index as in fn1 , fn2 , fn3 , and then invoke these dynamically using feval(['fn', num2str(k)], x, y, z); .

Answer 2

Until Release 14 (MATLAB 7), feval was the way to evaluate a function handle... or to evaluate functions when they are specified by their name.

Source: Mental model for feval() .

Answer 3

Not necessarily always you know what function is supposed to used; there are many examples

here is a silly example: let, in a text file after each number, different word that can be evaluated as a mathematical function, like, mean, min, max, square are represented, and the task is calculating the result after each like,

2,square,2,power,4,log,10 ...

and you want to write a program to go through this text and calculate the final result ...

another example is for example, I want to define a plot function with user input function handle f, so it must be in a way flexible ...

pfun=@(f,x) plot(f(x))