std::rand

 

C++

Linguaggio

Concetti

Libreria di Utilità

Stringhe

Contenitori

Algoritmi

Iteratori

Libreria matematca

Input/output

Localizzazione

Espressioni regolari(C++11)

Operazioni atomicche(C++11)

Multithreading(C++11)

 

Numeri libreria

Comuni funzioni matematiche

Virgola mobile ambiente

I numeri complessi

Array numerici

Pseudo-casuale generazione

In fase di compilazione aritmetica razionale(C++11)

Generici operazioni numeriche 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

 

Pseudo-casuale generazione

Motori e adattatori del motore 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)

Generatori 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)

Distribuzioni Original: Distributions The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

Distribuzioni uniformi Original: Uniform distributions The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

uniform_int_distribution (C++11)

uniform_real_distribution (C++11)

generate_canonical (C++11)

Bernoulli distribuzioni 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)

Poisson distribuzioni 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)

extreme_value_distribution (C++11)

Distribuzioni normali Original: Normal distributions The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

normal_distribution (C++11)

lognormal_distribution (C++11)

chi_squared_distribution (C++11)

cauchy_distribution (C++11)

fisher_f_distribution (C++11)

student_t_distribution (C++11)

Distribuzioni di campionamento Original: Sampling distributions The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

discrete_distribution (C++11)

piecewise_constant_distribution (C++11)

piecewise_linear_distribution (C++11)

Seed Sequenze 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)

Libreria C 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

 

Elemento definito nell'header <cstdlib>
int rand();

Restituisce un uniformemente distribuiti valore pseudo-casuale integrale tra ​0​ e RAND_MAX (0 e RAND_MAX inclusi).

Original:

Returns a uniformly distributed pseudo-random integral value between ​0​ and RAND_MAX (0 and RAND_MAX included).

The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.

srand() deve essere chiamato prima di qualsiasi chiamata a rand() per inizializzare il generatore di numeri casuali.

Original:

srand() should be called before any calls to rand() to initialize the random number generator.

The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.

Parametri

(Nessuno)

Original:

(none)

The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.

Valore di ritorno

Pseudo-casuale tra valore integrale ​0​ e RAND_MAX.

Original:

Pseudo-random integral value between ​0​ and RAND_MAX.

The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.

Esempio

#include <cstdlib>#include <iostream>#include <ctime>   int main(){std::srand(std::time(0));//use current time as seed for random generatorint uniform_random_variable = std::rand();std::cout<<"Uniform random value on [0 "<<RAND_MAX<<"]: "<< uniform_random_variable <<'\n';}

Possible output:

Uniform random value on [0 2147483647]: 1373858591

Vedi anche

srand	inizializza pseudo-generatore di numeri casuali Original: initializes pseudo-random number generator The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (funzione)
C documentation for rand