Check out example codes for "declaring a function in matlab". It will help you in understanding the concepts better.

Code Example 1

function f = fact(n)
    f = prod(1:n);
end

Code Example 2

function ave = average(x)
    ave = sum(x(:))/numel(x); 
end

Code Example 3

%%%% general syntax %%%%%%%%%%%%%
function [return parameters] = name_of_function(attributes)
	%%%%%%%%%%%%%%%%%%%%%%%%%%%%
    body_of_the_function
    %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
    
end

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