MATLAB: Finding the time difference between both the functions

function timing

These are my 2 functions, is there a way of putting them into a script and comparing their running times?
   function nprimes(N)
n = 1;
nPrimes = 0; 
   while nPrimes < N 
    if isprime(n)
        fprintf('%i\n',n)
        nPrimes = nPrimes + 1;
    end
    n = n + 1;         
end
end
 function p = nprimes(N)
p = [];
if N == 1
    p = 2;
elseif N == 2
    p = [2 3];
else
    pn1 = nprimes(N-1);
    plast = pn1(end) + 1;
    while ~isprime(plast) 
        plast = plast + 1;
    end;
    p = [nprimes(N-1), plast];
end;

Best Answer

If you put them in a single file (obviously with different names) that starts with a function (name it whatever you want, but it has to be a function, not a script in this case) then e.g.
function compareTimes( )
N = 27;
t1 = timeit( @( ) nprimes1( N ) )
t2 = timeit( @( ) nprimes2( N ) )
end
function nprimes1( N )
...
end
function nprimes2( N )
...
end
You can just use nested functions if you prefer, though I wouldn't do this in this case if you are trying to test the function with an argument passed in rather than in a context where it shares its workspace with some other function that won't be there in a general context.
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