std::philox_engine<UIntType,w,n,r,consts>::philox_engine

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philox_engine() : philox_engine(default_seed) {}	(1)	(since C++26)
explicit philox_engine( result_type value );	(2)	(since C++26)
template< class SeedSeq > explicit philox_engine( SeedSeq& seq );	(3)	(since C++26)
philox_engine( const philox_engine& other );	(4)	(since C++26) (implicitly declared)

Constructs the pseudo-random number engine.

1) The default constructor.

If the default-constructed engine is of type std::philox4x32, the 10000th consecutive invocation of it produces the value 1955073260.
If the default-constructed engine is of type std::philox4x64, the 10000th consecutive invocation of it produces the value 3409172418970261260.

2) Constructs the engine with a seed value value. The engine's initial state is determined as follows:^[1]

All elements of the sequence X are set to zero.
The first element of the sequence K is set to $\scriptsize value \mod 2^w$ $value mod 2 w$ , the remaining elements are set to zero.
The value of j is set to n - 1.

3) Constructs the engine with a seed sequence seq. The engine's initial state is determined as follows:^[1]

All elements of the sequence X are set to zero.
Given (w - 1) / 32 + 1 as p, the elements of the sequence K are set by the following steps:

Creates an invented array object a of length n / 2 * p.
Calls seq.generate(a + 0, a + n / 2 * p).
For each integer k in [0, n / 2), sets $\scriptsize K_k$ $K k$ to $\scriptsize (\sum^{p-1}_{i=0} a_{k \cdot p+i} \cdot 2^{32i}) \mod 2^w$ $(\sum p-1 i=0 a k\cdotp+i \cdot2 32i) mod 2 w$ .

This overload participates in overload resolution only if SeedSeq meets the requirements of SeedSequence.

4) The copy constructor. Upon construction, *this == other is true.

↑ ^1.0 ^1.1 The buffer Y is intentionally not being set. As j is being set to n - 1, the next state transition always generates new random values and stores them in Y.

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value	-	seed value to use in the initialization of the internal state
seq	-	seed sequence to use in the initialization of the internal state

1,2) Constant.

3) Same as the complexity of the seq.generate call.

4) Constant.

3) If SeedSeq is not std::seed_seq, throws the exceptions thrown by the seq.generate call.

seed	sets the current state of the engine (public member function) [edit]
set_counter	sets the current counter of the engine (public member function) [edit]

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