notation

what does () mean in the line below?

x=somefunction()

Answer 1

[Wayne King]

Then somefunction.m does not take input arguments for example:

function x = somefunction
x = 2;
end

if you call

x = somefunction()

you get x = 2

you can also just enter

x = somefunction;

Answer 2

[Wayne King]

The way you've written it, it implies that you are calling a function called somefunction that returns an output x. Inside the parentheses is where you supply any input arguments, name-value pairs, etc.

[Baba]

but in the code that I have, there are no parameters inside the parenthese.

Answer 3

[Walter Roberson]

Then it is a function call with no parameters supplied.

Ordinary MATLAB functions that do not need a parameter, can be called either with the () notation or just by giving the function name. For example,

x = pi + rand;

is equivalent to

x = pi() + rand();

as "pi" and "rand" are both functions in MATLAB.

However, if somefunction were a function handle, then

x = somefunction;

would not call the function: instead it would copy the function handle. But

x = somefunction();

would invoke the function whether it was a regular function or a function handle.