std::mersenne_twister_engine and random number generation

Question

What is the distribution (uniform, poisson, normal, etc.) that is generated if I did the below? The output appears to indicate a uniform distribution. But then, why do we ne

Answer 1

The random engine std::mt19937_64 outputs a 64-bit number that behaves like a uniformly distributed random number. Each of the C++ random engines (including those of the std::mersenne_twister_engine family) outputs a uniformly-distributed pseudorandom number of a specific size using a specific algorithm.

Specifically, std::mersenne_twister_engine meets the RandomNumberEngine requirement, which in turn meets the UniformRandomBitGenerator requirement; therefore, std::mersenne_twister_engine outputs bits that behave like uniformly-distributed random bits.

On the other hand, std::uniform_int_distribution is useful for transforming numbers from random engines into random integers of a user-defined range (say, from 0 through 10). But note that uniform_int_distribution and other distributions (unlike random number engines) can be implemented differently from one C++ standard library implementation to another.