MATLAB: Generation of random numbers in batches

prngrandom number

Hello,

Imagine the following code in Matlab

rng(1)
a = rand(1,100)
rng(1)
a2 = rand(1,200);

These are two random generators initialized with the same seed. The elements in a are equal to the 100 first elements in a2.

Now, I want to create a random sequence a3 that satisfies a2 = [a, a3].

How should I choose the seed of a3 to satisfy a2? is this even possible?

Best

Found the answer.

Just need to store the state of the generator with s = rng and initialize with rng(s) the next generation

Thanks for your help

I think you should use the newer rng

    rng default;
    x = randn(100,1);
    rng default
    y = randn(100,1);
    max(abs(x-y))

x and y are the same sequence.

In general, you can capture the random generator settings and resuse them

   S = rng;
   x = randn(100,1);
   rng(S)
   y = randn(100,1);

s = rng;   % rng seeds the random number generator
seq1 = rand(1,5);
rng(s);
seq2=rnd(1,5);