On Saturday, 3 August 2019 at 17:47:46 UTC, Giovanni Di Maria
On Saturday, 3 August 2019 at 17:44:44 UTC, lithium iodate
On Saturday, 3 August 2019 at 16:35:34 UTC, Giovanni Di Maria
First off you could try to use a faster RNG engine than the
default. The easiest way is to define a variable containing it
and passing it to the functions each time.
auto rng = Xorshift(1234);
randomNumber = uniform!uint(rng);
This basic change approximately halved the 5 seconds your
original example needs on my computer.
Another simple approach that I have tried is simply hashing
the iterator using a fast hash function.
With xxHash32 I got the time down to 0.25 seconds. I also
tried xxHash64 and FNV1a but they were not faster in my quick
Thank you very much Lithium Iodate
Now i will try it.
I let know you.
If it doesn't matter if it's predictable or not then you could
easily make your own simple random generator with would give
Of course in general it's not usable:
T abs(T)(T x)
T y = x > 0 ? T.max : cast(T)0;
return (x ^ y) - y;
_seed = cast(uint)time(null);
_interval = (_seed - 20559);
T next(T)(T max)
auto value = cast(T)(abs(_interval) % T.max);
_interval -= (_interval / 10) * _seed;
auto random = new Random;
foreach (_; 0 .. 1000)
auto result = random.next!ubyte(255);