rand_seed - Skys docwiki

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rand_seed

void rand_seed(uint seed, uint index)

Use this function to create a repeatable sequence of random numbers.
Seed is used to start the sequence, while index tells the function to begin with the index-th number. Incrementing index is the same as calling rand() one more time after rand_seed.

Note: The random number generator is seeded at program startup with a good number. There is no need to do that every time yourself.

Example:

import std.stdio;
import std.random;

void main()
{
    const int max = 3;
    writefln("Before rand_seed() called...");
    for(int i = 1; i <= max; i++)
       writefln("rand() is %12d", rand());

    rand_seed(1,0);
    writefln("\nAfter rand_seed(1,0) called...");
    for(int i = 1; i <= max; i++)
       writefln("rand() is %12d", rand());

    rand_seed(1,1);
    writefln("\nAfter rand_seed(1,1) called...");
    for(int i = 1; i <= max; i++)
       writefln("rand() is %12d", rand());
}

Output could be:

Before rand_seed() called...
rand() is   3504812646
rand() is    904386554
rand() is    373390471

After rand_seed(1,0) called...
rand() is     48551977
rand() is   1352404003
rand() is    370828309

After rand_seed(1,1) called...
rand() is   1352404003
rand() is    370828309
rand() is   1385419666