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std::generate_canonical(3)     C++ Standard Libary    std::generate_canonical(3)

NAME
     std::generate_canonical - std::generate_canonical

Synopsis
	Defined in header <random>
	template<  class  RealType,  std::size_t Bits, class Generator >  (since
     C++11)
	RealType generate_canonical( Generator& g );

	Generates a random floating point number in range [0, 1).

	To generate enough entropy, generate_canonical() will call  g()  exactly
     \(\small k\)k
	times, where \(\small k = \max(1, \lceil \frac{b}{\log_2 R} \rceil)\)k =
     max(1, a b
	/ log
	2 R a) and

	  *  b = std::min(Bits, std::size_t {std::numeric_limits<RealType>::dig-
     its}),
	  * R = g.max() - g.min() + 1.

Parameters
	g - generator to use to acquire entropy

Return value
	Floating point value in range [0, 1).

Exceptions
	None except from those thrown by g.

Notes
	Some existing implementations have a bug where they may occasionally re-
     turn 1.0 if
	RealType is float GCC #63176 LLVM #18767 MSVC STL #1074. This is LWG is-
     sue 2524.

Example
	Produce random numbers with 10 bits of randomness: this may produce only
     k * R
	distinct values.

     // Run this code

      #include <iostream>
      #include <random>

      int main()
      {
	  std::random_device rd;
	  std::mt19937 gen(rd());
	  for (int n = 0; n < 10; ++n)
	      std::cout << std::generate_canonical<double, 10>(gen) << ' ';
	  std::cout << '\n';
      }

Possible output:
      0.208143 0.824147 0.0278604 0.343183 0.0173263 0.864057 0.647037	0.539467
     0.0583497 0.609219

See also
	uniform_real_distribution produces real values evenly distributed across
     a range
	(C++11) 		  (class template)

http://cppreference.com 	   2024.06.10	      std::generate_canonical(3)
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