For questions related to the Mersenne Twister pseudorandom number generator with a period of 2^19337
Questions tagged [mt19937]
39 questions
1
vote
4 answers
C++ mt19937 getting the same sequence multiple times
I'm trying to create a deterministic hash generator using a pseudo random number sequence with the mt19937 engine in the library. Therefore, I need to get the same sequence of numbers every time I feed the engine with the same seed.
My code…
Pizza Monkey
- 11
- 1
1
vote
1 answer
Function not updating internal state of mt19937
I have a function that generates and writes random integers:
void randint(int min, int max, int times,std::mt19937 rng){
std::uniform_int_distribution dist(min, max);
for (int i=0;i
44a3
- 35
- 4
1
vote
0 answers
What are the advantages of using a fixed value as the first state in NumPy MT19937?
In NumPy's current implementation, the MT19937 generator takes an entropy input (int or sequence of int), passes it to a hash function implemented by SeedSequence, and uses the returned sequence of numbers as initial state values, except the first…
DanielTuzes
- 2,494
- 24
- 40
1
vote
1 answer
static and random generator in c++
#include
#include
int gen_ran(void)
{
static std::random_device rd;
static std::mt19937 gen(rd());
static std::uniform_int_distribution dist(0, 9);
return dist(gen);
}
int main()
{
for (int i = 0; i <…
Ethan
- 161
- 2
- 9
1
vote
1 answer
Visual Studio 2019 c++latest generic URNG function fails to compile after latest update
I have the following generic C++ generic URNG function:
template
void TestURNG(URNG& urng)
{
// Uniform distribution used with vector
// Distribution is [-5, 5] inclusive
uniform_int_distribution dist(-5, 5);
…
Kok How Teh
- 3,298
- 6
- 47
- 85
1
vote
1 answer
How to initialize std::mt19937 when std::random_device entropy is unknown? (VS C++/Windows)
I am attempting to build a simple random number generator, but I wanted to make sure random_device was working properly. I started with the following code:
#include
#include
class Generator {
public:
Generator()
:
…
Jatol
- 51
- 4
1
vote
1 answer
How is mt19937 prng exactly used for python random module functions?
from random import *
seed(5489)
hex(getrandbits(32)) # '0xc9a0e034'
hex(getrandbits(32)) # '0x38feb21f'
I ran this with Python 3.8.2 (not that it should matter too much). This is not what I would expect from a MT19937 32 bit PRNG. To be exact, I…
adbforlife
- 21
- 7
1
vote
1 answer
Chosing the random-number-generator at runtime in CPP
I am probably doing more effort than necessary but who cares, let's try to solve this problem:
I would like to use the "random_device" generator from in my code. But that might not be available on some systems (according to specs), so I…
István
- 11
- 4
1
vote
0 answers
How can I use mt19937 in a class without getting the same random sequence in each instance?
I'm writing code for initializing particle positions in a phase space using a density function. I would like to randomly sample their locations according to an arbitrary distribution, and the easiest way to do this that I found was to make a small…
Liam Clink
- 189
- 1
- 11
0
votes
1 answer
mt19997 C++ object passed by reference always generates the same values
I'm trying to write a code where I create an object mt19937 in a class A that can be used in the class internal functions for generating random numbers and I also want to pass a reference to this same object to various instances of the class B…
Bryan Barbosa
- 1
- 1
0
votes
1 answer
It is proper to make mt19937 static in a class
Let's say I have a class as below:
class Test {
public:
Test() : mt((std::random_device())()), dist1(0, 10), dist2(0, 100) {}
void func() {
if (dist1(mt) < 4) {
// do something
}
}
void func2() {
…
Yves
- 11,597
- 17
- 83
- 180
0
votes
0 answers
std::uniform_real_distribution gives only one number at mingw
I am try to run this code:
#include
#include
void foo() {
std::random_device rd;
std::mt19937 mt(rd());
std::uniform_real_distribution prob(0, 1);
std::cout << prob(mt) << '\n';
}
int main() {
for (int i = 0;…
dasfex
- 1,148
- 2
- 12
- 30
0
votes
0 answers
Random Number Generator with mt19937 Not Working Properly
The code is giving me the same number every time I run the program. I can't figure out why.
I looked up a tutorial on how to use the seed the generator properly, and for some reason my example won't work.
#include
#include
int…
John K
- 21
- 2
0
votes
0 answers
How to determine big O complexity for mt19937 algorithm
Create a length n array to store the state of the generator
int[0..n-1] MT
int index := n+1
const int lower_mask = (1 << r) - 1 // That is, the binary number of r 1's
const int upper_mask = lowest w bits of (not lower_mask)
Initialize the generator…
Ari Pili
- 21
- 1
0
votes
0 answers
C++ uniform_real_distribution keeps outputting the same values each time
#include
#include
using namespace std;
vector res;
int main()
{
srand(time(NULL));
std::random_device randomDevice;
std::mt19937 generator(randomDevice());
std::uniform_real_distribution…
Huy Le
- 1,439
- 4
- 19