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## Class template lagged_fibonacci_01

boost::random::lagged_fibonacci_01

## Synopsis

    // In header: <boost/random/lagged_fibonacci.hpp>

    template<typename RealType, int w, unsigned int p, unsigned int q>
    class lagged_fibonacci_01 {
    public:
      // types
      typedef RealType result_type;

      // construct/copy/destruct
      lagged_fibonacci_01();
      lagged_fibonacci_01(uint32_t);
      template<typename Generator> lagged_fibonacci_01(Generator &);
      template<typename It> lagged_fibonacci_01(It &, It);

      // public member functions
      void seed() ;
      void seed(uint32_t) ;
      template<typename Generator> void seed(Generator &) ;
      template<typename It> void seed(It &, It) ;
      result_type min() const;
      result_type max() const;
      result_type operator()() ;

      // public static functions
      static bool validation(result_type) ;
      static const bool has_fixed_range;
      static const int word_size;
      static const unsigned int long_lag;
      static const unsigned int short_lag;
    };

## Description

Instantiations of class template `lagged_fibonacci_01` model a pseudo-random number generator . It uses a lagged Fibonacci algorithm with two lags `p` and `q`, evaluated in floating-point arithmetic: x(i) = x(i-p) + x(i-q) (mod 1) with p > q. See

> "Uniform random number generators for supercomputers", Richard Brent, Proc. of Fifth Australian Supercomputer Conference, Melbourne, Dec. 1992, pp. 704-706.

| Note
The quality of the generator crucially depends on the choice of the parameters. User code should employ one of the sensibly parameterized generators such as lagged_fibonacci607 instead.

The generator requires considerable amounts of memory for the storage of its state array. For example, lagged_fibonacci607 requires about 4856 bytes and lagged_fibonacci44497 requires about 350 KBytes.

### `lagged_fibonacci_01` public construct/copy/destruct

1.     lagged_fibonacci_01();

   Constructs a `lagged_fibonacci_01` generator and calls `seed()`.

2.     lagged_fibonacci_01(uint32_t value);

   Constructs a `lagged_fibonacci_01` generator and calls `seed(value)`.

3.     template<typename Generator> lagged_fibonacci_01(Generator & gen);

   Constructs a `lagged_fibonacci_01` generator and calls `seed(gen)`.

4.     template<typename It> lagged_fibonacci_01(It & first, It last);

### `lagged_fibonacci_01` public member functions

1.     void seed() ;

   Calls seed(331u).

2.     void seed(uint32_t value) ;

   Constructs a `minstd_rand0` generator with the constructor parameter value and calls seed with it. Distinct seeds in the range [1, 2147483647) will produce generators with different states. Other seeds will be equivalent to some seed within this range. See `linear_congruential` for details.

3.     template<typename Generator> void seed(Generator & gen) ;

   Sets the state of this `lagged_fibonacci_01` to the values returned by p invocations of `uniform_01``<RealType>()(gen)`.

   Complexity: Exactly p invocations of gen.

4.     template<typename It> void seed(It & first, It last) ;

5.     result_type min() const;

6.     result_type max() const;

7.     result_type operator()() ;

### `lagged_fibonacci_01` public static functions

1.     static bool validation(result_type x) ;