Normal distribution

[Joseph Rushton Wakeling via Digitalmars-d]

On Friday, 26 February 2016 at 19:11:15 UTC, John Colvin wrote:
> On Friday, 26 February 2016 at 18:23:41 UTC, Andrei 
> Alexandrescu wrote:
>> On 02/20/2016 09:06 AM, Edwin van Leeuwen wrote:
>>> On Saturday, 20 February 2016 at 14:01:22 UTC, Andrei 
>>> Alexandrescu wrote:
>>>> Do we have a good quality converter of uniform numbers to
>>>> Gaussian-distributed numbers around? -- Andrei
>>>
>>> There is one in dstats:
>>> https://github.com/DlangScience/dstats/blob/master/source/dstats/random.d#L266
>>
>> Thanks! I ended up using this. Is someone working on adding 
>> Gaussians to phobos? -- Andrei
>
> https://github.com/WebDrake/hap is intended as a replacement 
> for std.random and includes distributions (see e.g. 
> https://github.com/WebDrake/hap/blob/master/source/hap/random/distribution.d#L441). Also, remember http://dconf.org/2015/talks/wakeling.html

Yup.  The basic problem of getting this stuff into phobos are the 
architectural problems discussed in that talk.  Unlike uniform 
distribution (which is straightforward to implement as a 
function, no questions asked), the normal distribution is best 
implemented as a range which keeps some state.  So the 
reference-type/non-reference-type issues start becoming a factor.

That said, it's _possible_ to implement a simple 
normal-variate-generator as a function, it's just inefficient.