Class template independent_bits_engine

boost::random::independent_bits_engine

Synopsis

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

template<typename Engine, std::size_t w, typename UIntType> 
class independent_bits_engine {
public:
  // types
  typedef Engine              base_type;       
  typedef UIntType            result_type;     
  typedef Engine::result_type base_result_type;

  // construct/copy/destruct
  independent_bits_engine();
  explicit independent_bits_engine(base_result_type);
  template<typename SeedSeq> explicit independent_bits_engine(SeedSeq &);
  independent_bits_engine(const base_type &);
  template<typename It> independent_bits_engine(It &, It);

  // public static functions
  static constexpr result_type min();
  static constexpr result_type max();

  // public member functions
  void seed();
  void seed(base_result_type);
  template<typename SeedSeq> void seed(SeedSeq &);
  template<typename It> void seed(It &, It);
  result_type operator()();
  template<typename Iter> void generate(Iter, Iter);
  void discard(boost::uintmax_t);
  const base_type & base() const;

  // friend functions
  template<typename CharT, typename Traits> 
    friend std::basic_ostream< CharT, Traits > & 
    operator<<(std::basic_ostream< CharT, Traits > &, 
               const independent_bits_engine &);
  template<typename CharT, typename Traits> 
    friend std::basic_istream< CharT, Traits > & 
    operator>>(std::basic_istream< CharT, Traits > &, 
               const independent_bits_engine &);
  friend bool operator==(const independent_bits_engine &, 
                         const independent_bits_engine &);
  friend bool operator!=(const independent_bits_engine &, 
                         const independent_bits_engine &);

  // public data members
  static const bool has_fixed_range;
};

Description

An instantiation of class template independent_bits_engine model a pseudo-random number generator . It generates random numbers distributed between [0, 2^w) by combining one or more invocations of the base engine.

Requires: 0 < w <= std::numeric_limits<UIntType>::digits

`independent_bits_engine` public construct/copy/destruct

```
independent_bits_engine();
```
Constructs an independent_bits_engine using the default constructor of the base generator.
```
explicit independent_bits_engine(base_result_type seed);
```
Constructs an independent_bits_engine, using seed as the constructor argument for both base generators.
```
template<typename SeedSeq> explicit independent_bits_engine(SeedSeq & seq);
```
Constructs an independent_bits_engine, using seq as the constructor argument for the base generator.

independent_bits_engine(const base_type & base_arg);

Constructs an independent_bits_engine by copying base.

```
template<typename It> independent_bits_engine(It & first, It last);
```
Contructs an independent_bits_engine with values from the range defined by the input iterators first and last. first will be modified to point to the element after the last one used.

Throws: std::invalid_argument if the input range is too small.

Exception Safety: Basic

`independent_bits_engine` public static functions

```
static constexpr result_type min();
```
Returns the smallest value that the generator can produce.
```
static constexpr result_type max();
```
Returns the largest value that the generator can produce.

`independent_bits_engine` public member functions

```
void seed();
```
Seeds an independent_bits_engine using the default seed of the base generator.
```
void seed(base_result_type seed);
```
Seeds an independent_bits_engine, using seed as the seed for the base generator.
```
template<typename SeedSeq> void seed(SeedSeq & seq);
```
Seeds an independent_bits_engine, using seq to seed the base generator.
```
template<typename It> void seed(It & first, It last);
```
Seeds an independent_bits_engine with values from the range defined by the input iterators first and last. first will be modified to point to the element after the last one used.

Throws: std::invalid_argument if the input range is too small.

Exception Safety: Basic
```
result_type operator()();
```
Returns the next value of the generator.

template<typename Iter> void generate(Iter first, Iter last);

Fills a range with random values

```
void discard(boost::uintmax_t z);
```
Advances the state of the generator by z.
```
const base_type & base() const;
```

`independent_bits_engine` friend functions

template<typename CharT, typename Traits> 
  friend std::basic_ostream< CharT, Traits > & 
  operator<<(std::basic_ostream< CharT, Traits > & os, 
             const independent_bits_engine & r);

Writes the textual representation if the generator to a std::ostream. The textual representation of the engine is the textual representation of the base engine.

template<typename CharT, typename Traits> 
  friend std::basic_istream< CharT, Traits > & 
  operator>>(std::basic_istream< CharT, Traits > & is, 
             const independent_bits_engine & r);

Reads the state of an independent_bits_engine from a std::istream.

friend bool operator==(const independent_bits_engine & x, 
                       const independent_bits_engine & y);

Returns: true iff the two independent_bits_engines will produce the same sequence of values.

friend bool operator!=(const independent_bits_engine & lhs, 
                       const independent_bits_engine & rhs);

Returns: true iff the two independent_bits_engines will produce different sequences of values.

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