std::seed_seq::generate

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Biblioteca numéricos

Pseudo-aleatório de geração de números

Motores e adaptadores de motor Original: Engines and engine adaptors The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
linear_congruential_engine (C++11)
mersenne_twister_engine (C++11)
subtract_with_carry_engine (C++11)
discard_block_engine (C++11)
independent_bits_engine (C++11)
shuffle_order_engine (C++11)
Geradores Original: Generators The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
random_device (C++11)
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uniform_int_distribution (C++11)
uniform_real_distribution (C++11)
generate_canonical (C++11)
Distribuições de Bernoulli Original: Bernoulli distributions The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
bernoulli_distribution (C++11)
binomial_distribution (C++11)
negative_binomial_distribution (C++11)
geometric_distribution (C++11)
Distribuições de Poisson Original: Poisson distributions The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
poisson_distribution (C++11)
exponential_distribution (C++11)
gamma_distribution (C++11)
weibull_distribution (C++11)
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Seqüências de sementes Original: Seed Sequences The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
seed_seq (C++11)
C biblioteca Original: C library The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
rand
srand
RAND_MAX

[edit]


`template< class RandomIt > void generate( RandomIt begin, RandomIt end );`		(desde C++11)

Preenche a [begin, end) faixa com valores inteiros sem sinal i,

0 \leq i < 2 32

, com base nos dados originalmente fornecidos no construtor desta seed_seq. Os valores produzidos são distribuídos ao longo da gama de 32-bit inteiro, mesmo que os valores iniciais foram fortemente inclinado.

O seguinte algoritmo é utilizado (adaptado a partir da seqüência de inicialização do Mersenne Twister gerador por Makoto Matsumoto and Takuji Nishimura, incorporando as melhorias feitas pela Mutsuo Saito in 2007)

Se begin == end, não faça nada. Caso contrário,
Original:
If begin == end, do nothing. Otherwise,
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Em primeiro lugar, definir cada elemento da faixa de saída para o valor 0x8b8b8b8b
Original:
First, set each element of the output range to the value 0x8b8b8b8b
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Transformar os elementos da gama de saída de acordo com o seguinte algoritmo:
Original:
Transform the elements of the output range according to the following algorithm:
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For k = 0,..., m-1

onde m=max(s+1, n)

and n=begin-end
and s=v.size()

e v é o recipiente privado mantendo os valores originalmente previstos pelo construtor deste objeto seed_seq

begin[k+p] += r1
begin[k+q] += r2
begin[k] = r2,

onde p=(n-t)/2

and q=p+t
and t=(n >= 623) ? 11 : (n >= 68) ? 7 : (n >= 39) ? 5 : (n >= 7) ? 3 : (n - 1) / 2
and r1=1664525 * T(begin[k]^begin[k+p]^begin[k−1])
and T(x) = x ^ (x << 27)
and r2=r1+s if k==0, r2=r1 + k%n + v[k-1] if 0<k<=s, r2=r1 + k%n if k>s.

For k = m,..., m+n-1,

begin[k+p] ^= r3
begin[k+q] ^= r4
begin[k]=r4

onde r3 = 1566083941 * T(begin[k]+begin[k+p]+begin[k-1])

and r4=r3 - k%n

onde todos os cálculos são executados

modulo 2 32

e onde a indexação do intervalo de saída (begin[x]) é tomado

modulo n

.

Parâmetros

begin, end	-	mutáveis de acesso aleatório iteradores cujos `std::iterator_traits<>::value_type` é um tipo inteiro sem sinal adequado para o armazenamento de valores de 32 bits Original: mutable random-access iterators whose `std::iterator_traits<>::value_type` is an unsigned integer type suitable for storing 32-bit values The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
Type requirements
- `RandomIt` must meet the requirements of `RandomAccessIterator`.

Valor de retorno

nenhum, os resultados são escritos no intervalo [begin, end).

Exemplo

#include <random>
#include <iostream>

int main()
{
    std::seed_seq seq({1,2,3,4,5});
    std::vector<std::uint32_t> seeds(10);
    seq.generate(seeds.begin(), seeds.end());
// Step 1: fill with 0x8b8b8b8b
// seeds = {2341178251, 2341178251, 2341178251, 2341178251, 2341178251,
//          2341178251, 2341178251, 2341178251, 2341178251, 2341178251 }
//
// Step 2: 
// n = 10, s = 5, t = 3, p = 3, q = 6, m = 10
//
// First iteration, k = 0; r1 = 1371501266, r2 = 1371501271
//
// seeds = {1371501271, 2341178251, 2341178251, 3712679517, 2341178251,
//          2341178251, 3712679522, 2341178251, 2341178251, 2341178251 }
//
// Iterations from k = 1 to k = 5 (r2 = r1 + k%n + v[k-1])
//
// r1 = 2786190137, 3204727651, 4173325571, 1979226628, 401983366
// r2 = 2786190139, 3204727655, 4173325577, 1979226636, 401983376
//
// seeds = {3350727907, 3188173515, 3204727655, 4173325577, 1979226636,
//           401983376, 3591037797, 2811627722, 1652921976, 2219536532 } 
//
// Iterations from k = 6 to k = 9 (r2 = r1 + k%n)
//
// r1 = 2718637909, 1378394210, 2297813071, 1608643617
// r2 = 2718637915, 1378394217, 2297813079, 1608643626
//
// seeds = { 434154821, 1191019290, 3237041891, 1256752498, 4277039715,
//          2010627002, 2718637915, 1378394217, 2297813079, 1608643626 } 
//
// Step 3
// iterations from k = 10 to k = 19, using ^= to modify the output
//
// r1 = 1615303485, 3210438310, 893477041, 2884072672, 1918321961,
// r2 = 1615303485, 3210438309, 893477039, 2884072669, 1918321957
//
// seeds = { 303093272, 3210438309,  893477039, 2884072669, 1918321957,
//          1117182731, 1772877958, 2669970405, 3182737656, 4094066935 }
//
// r1 =  423054846, 46783064, 3904109085, 1534123446, 1495905687
// r2 =  423054841, 46783058, 3904109078, 1534123438, 1495905678
//
// seeds = { 4204997637, 4246533866, 1856049002, 1129615051, 690460811,
//           1075771511,   46783058, 3904109078, 1534123438, 1495905678 }

    for(std::uint32_t n : seeds)
        std::cout << n << '\n';
}

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Biblioteca de diagnósticos
Biblioteca de utilitários em geral
Biblioteca de strings
Biblioteca de containers
Ranges library (C++20)
Biblioteca de iteradores
Biblioteca de algorítmos
Biblioteca numérica
Biblioteca de localizações
Biblioteca de input/output
Biblioteca de sistema de arquivo (C++17)
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Especificações Técnicas
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Funções matemáticas comuns
De ponto flutuante ambiente
Números complexos
Matrizes numéricas
Pseudo-aleatório de geração de números
Tempo de compilação aritmética racional (C++11)
Genéricos operações numéricas Original: Generic numeric operations The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
iota (C++11)
accumulate
inner_product
adjacent_difference
partial_sum

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std::seed_seq::generate

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