In IJulia, it's about 1.8 mSec no matter how many times I run it. In the
command window, it's about 57 microSeconds the second time. Why is that?
On Thursday, September 17, 2015 at 4:07:29 PM UTC-4, Elliot Saba wrote:
>
> Because Julia is a just-in-time compiled language, the first time you run
> something, it gets compiled immediately before running it. Therefore, we
> suggest you time the execution after "warming up" the JIT:
>
> julia> fib(n) = n < 2 ? n : fib(n-1) + fib(n-2)
> fib (generic function with 1 method)
>
> julia> @time fib(20)
> elapsed time: 0.003523425 seconds (47856 bytes allocated)
> 6765
>
> julia> @time fib(20)
> elapsed time: 0.000144034 seconds (96 bytes allocated)
> 6765
>
> julia> @time fib(20)
> elapsed time: 0.000143337 seconds (96 bytes allocated)
> 6765
>
>
> Also note that the @time macro is doing the printing, so you don't need
> the parentheses or the println() call for this.
>
> On Thu, Sep 17, 2015 at 12:53 PM, Frank Kampas <fka...@gmail.com
> <javascript:>> wrote:
>
>> On julialang.org, it is stated that Julia is about 170 times faster than
>> Mathematica for the the test "fib". I get about a factor 2.
>>
>> Julia:
>>
>> fib(n) = n < 2 ? n : fib(n-1) + fib(n-2)
>> println(@time(fib(20)))
>>
>> elapsed time: 0.001868071 seconds (33280 bytes allocated)
>> 6765
>>
>>
>> Mathematica:
>>
>>
>> In[1]:= AbsoluteTiming[fib =
>> Compile[{{n,_Integer}},If[n<2,n,fib[n-1]+fib[n-2]]]]
>> Out[1]= {0.000134563,CompiledFunction[Argument count: 1
>> Argument types: {_Integer}]}
>>
>>
>>
>> In[2]:= AbsoluteTiming[fib[20]]
>> Out[2]= {0.00385017,6765}
>>
>>
>>
>>
>>
>
