Put a function around the code and everything works as expected:

function perf()

    nsamples = 1000000;


    x = linspace(0, 5, nsamples);

    y = zeros(nsamples);

    noise = zeros(nsamples);

    

    a = rand(); a = cos(0.0); a = 1.5*2.5; a = 1.5+2.5;

    

    println("\nBrutal-force loops, 100 times:")

    for m = 1:100

        morenoise = rand();

        for n = 1:nsamples

            noise[n] = rand();

            y[n] = cos(2*x[n]+5) + noise[n] + morenoise;

        end

    end

end


@time(perf())


*Brutal-force loops, 100 times:*

*  2.964993 seconds (151.75 k allocations: 21.837 MB, 0.68% gc time)*


On Monday, July 11, 2016 at 8:57:05 AM UTC+2, Zhong Pan wrote:
>
> Hi,
>
> For work I really desired a language for numerical / data processing 
> that's as easy and capable as Python but still fast running loops. That's 
> why I am very excited when I noticed Julia. First allow me to me say, 
> fabulous work! I really appreciate the effort of those who make open-source 
> software great for everyone.
>
> I did a simple & naive benchmark involving brutal-force loops with some 
> floating-point calculations on Windows (have to use Windows for work). I 
> measured execution time in Python, Julia, VC++, C#.NET, Java, and Matlab. 
> To my surprise, Julia is not only much slower than VC++ in this test, but 
> it's much slower than C#.NET, Java, and even Matlab.
>
> Please see details of the test in the attached PDF file. Could someone 
> help me out here - did I make an amateur mistake or miss something? Was 
> Julia slow because of Windows? Or was it just the loops that's slow (as 
> this "benchmark" really didn't test anything else)? I really want to make 
> Julia my go-to language in work, so any suggestion is appreciated.
>
> Cheers.
> -Zhong
>
>
>

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