You can use std::generate algorithm to fill a vector of n elements with random numbers. In modern C++ it’s recommended not to use any time-based seeds and std::rand, but instead to use random_device to generate a seed. For software-based engine, you always need to specify the engine and distribution. Read More.. #include <random> #include <algorithm> … Read more
Use the new <random> header instead. It allows for multiple engine instances, using different algorithms and more importantly for you, independent seeds. [edit] To answer the “useful” part, rand generates random numbers. That’s what it’s good for. If you need fine-grained control, including reproducibility, you should not only have a known seed but a known … Read more
This is what I’ve used for small command line programs that can be run frequently (multiple times a second): unsigned long seed = mix(clock(), time(NULL), getpid()); Where mix is: // Robert Jenkins’ 96 bit Mix Function unsigned long mix(unsigned long a, unsigned long b, unsigned long c) { a=a-b; a=a-c; a=a^(c >> 13); b=b-c; b=b-a; … Read more
That depends on what you are trying to achieve. Randomization is performed as a function that has a starting value, namely the seed. So, for the same seed, you will always get the same sequence of values. If you try to set the seed every time you need a random value, and the seed is … Read more