On Wednesday, 15 January 2014 at 21:00:57 UTC, Jeroen Bollen wrote:
> How do you correctly create a MersenneTwisterEngine with a ulong as seed?

This question still isn't answered by the way.

On Friday, 17 January 2014 at 19:00:29 UTC, Jeroen Bollen wrote:
> On Wednesday, 15 January 2014 at 21:00:57 UTC, Jeroen Bollen wrote:
>> How do you correctly create a MersenneTwisterEngine with a ulong as seed?
>
> This question still isn't answered by the way.

Come on, surely someone knows how to. I've already tried the obvious, but it doesn't work.

MersenneTwisterEngine!(ulong, 32, 624, 397, 31, 0x9908b0df, 11, 7, 0x9d2c5680, 15, 0xefc60000, 18) rndEngine;
rndEngine = MersenneTwisterEngine(seed);

"shift by 32 is outside the range 0..31"
"static assert  (false && 4022730752LU <= 0LU) is false"
"instantiated from here: MersenneTwisterEngine!(ulong, 32, 624, 397, 31, 2567483615u, 11, 7, 2636928640u, 15, 4022730752u, 18)"

On Tuesday, 21 January 2014 at 17:13:39 UTC, Jeroen Bollen wrote:
> On Friday, 17 January 2014 at 19:00:29 UTC, Jeroen Bollen wrote:
>> On Wednesday, 15 January 2014 at 21:00:57 UTC, Jeroen Bollen wrote:
>>> How do you correctly create a MersenneTwisterEngine with a ulong as seed?
>>
>> This question still isn't answered by the way.
>
> Come on, surely someone knows how to. I've already tried the obvious, but it doesn't work.
>
> MersenneTwisterEngine!(ulong, 32, 624, 397, 31, 0x9908b0df, 11, 7, 0x9d2c5680, 15, 0xefc60000, 18) rndEngine;
> rndEngine = MersenneTwisterEngine(seed);
>
> "shift by 32 is outside the range 0..31"
> "static assert  (false && 4022730752LU <= 0LU) is false"
> "instantiated from here: MersenneTwisterEngine!(ulong, 32, 624, 397, 31, 2567483615u, 11, 7, 2636928640u, 15, 4022730752u, 18)"

Is that your actual code? "MersenneTwisterEngine(seed)" is not valid code, you have to provide the template arguments.

In any case, that's a bug. Please file a report for it, and I'll give it a full fix.

For a local fix, you can replace the incriminating line (random.d:550):
    /// Largest generated value.
    enum UIntType max =
        w == UIntType.sizeof * 8 ? UIntType.max : (1u << w) - 1;

By:
    /// Largest generated value.
    enum UIntType max =
        UIntType.max >> (UIntType.sizeof * 8 - w);

I think that's all that's required.

PS: If you want to generate longs, you also need to set the "w" variable (wordSize) from 32 to 64, or you'll still just be generating 32 bits worth of randomness.

I also recommend you use an alias (and alignment), such as:

    alias Mt19937UL =
        MersenneTwisterEngine!(ulong, 64, 624, 397, 31,
                               0x9908b0df, 11, 7,
                               0x9d2c5680, 15,
                               0xefc60000, 18);
    auto rndEngine = Mt19937UL(seed);

On Tuesday, 21 January 2014 at 17:51:44 UTC, monarch_dodra wrote:
> On Tuesday, 21 January 2014 at 17:13:39 UTC, Jeroen Bollen wrote:
>> On Friday, 17 January 2014 at 19:00:29 UTC, Jeroen Bollen wrote:
>>> On Wednesday, 15 January 2014 at 21:00:57 UTC, Jeroen Bollen wrote:
>>>> How do you correctly create a MersenneTwisterEngine with a ulong as seed?
>>>
>>> This question still isn't answered by the way.
>>
>> Come on, surely someone knows how to. I've already tried the obvious, but it doesn't work.
>>
>> MersenneTwisterEngine!(ulong, 32, 624, 397, 31, 0x9908b0df, 11, 7, 0x9d2c5680, 15, 0xefc60000, 18) rndEngine;
>> rndEngine = MersenneTwisterEngine(seed);
>>
>> "shift by 32 is outside the range 0..31"
>> "static assert  (false && 4022730752LU <= 0LU) is false"
>> "instantiated from here: MersenneTwisterEngine!(ulong, 32, 624, 397, 31, 2567483615u, 11, 7, 2636928640u, 15, 4022730752u, 18)"
>
> Is that your actual code? "MersenneTwisterEngine(seed)" is not valid code, you have to provide the template arguments.
>
> In any case, that's a bug. Please file a report for it, and I'll give it a full fix.
>
> For a local fix, you can replace the incriminating line (random.d:550):
>     /// Largest generated value.
>     enum UIntType max =
>         w == UIntType.sizeof * 8 ? UIntType.max : (1u << w) - 1;
>
> By:
>     /// Largest generated value.
>     enum UIntType max =
>         UIntType.max >> (UIntType.sizeof * 8 - w);
>
> I think that's all that's required.
>
> PS: If you want to generate longs, you also need to set the "w" variable (wordSize) from 32 to 64, or you'll still just be generating 32 bits worth of randomness.
>
> I also recommend you use an alias (and alignment), such as:
>
>     alias Mt19937UL =
>         MersenneTwisterEngine!(ulong, 64, 624, 397, 31,
>                                0x9908b0df, 11, 7,
>                                0x9d2c5680, 15,
>                                0xefc60000, 18);
>     auto rndEngine = Mt19937UL(seed);
That is my actual code.

On Tuesday, 21 January 2014 at 17:51:44 UTC, monarch_dodra
> Is that your actual code? "MersenneTwisterEngine(seed)" is not valid code, you have to provide the template arguments.

I meant to answer to this by the way, sorry. (in
need of edit feature :P )

On Tuesday, 21 January 2014 at 19:00:32 UTC, Jeroen Bollen wrote:
> On Tuesday, 21 January 2014 at 17:51:44 UTC, monarch_dodra
>> Is that your actual code? "MersenneTwisterEngine(seed)" is not valid code, you have to provide the template arguments.
>
> I meant to answer to this by the way, sorry. (in
> need of edit feature :P )

https://d.puremagic.com/issues/show_bug.cgi?id=11960

Now resolved fixed.