Re: Ada.Numerics.Float_Random.Generator question

[brbarkstrom@gmail.com]

On Saturday, September 17, 2016 at 3:40:13 PM UTC-4, Andrew Shvets wrote:
> Hello,
> 
> If I want a random float number to be generated, the way that I did this in the past was something along these lines:
> 
>   function Create_Random_Float(
>     From : in Float;
>     To : in Float)
>       return Float is
> 
>     Seed : Ada.Numerics.Float_Random.Generator;
>   begin
>     Ada.Numerics.Float_Random.Reset(Seed);
> 
>     return From + (Ada.Numerics.Float_Random.Random(Seed) * To);
>   end Create_Random_Float;
> 
> This works.  However, as I'm now looking into the Ada.Numerics.Discrete_Random package, I've noticed that it can generate a random value based on the type that is passed in.  This appeals to me and I'd like to do the same for a custom float type (say I want the delta to be 0.01.)
> 
> As Ada.Numerics.Float_Random.Generator is not a generic package, I can't use the same approach.  The best way that I can think of is to create the same result using From and To and then cast the result to the custom float type.
> 
> I hope that there is a better solution to this.  Is there?

Probably best consult Knuth on Random Numbers.  Complicated subject; lots
of numerical issues - testing involves some high-powered math.  See also
Park and Miller in CACM back a fer decades ago.

Bruce B.