Question

In Python, what is the best way to generate some random number using a certain seed but without reseeding the global state? In Java, you could write simply:

Random r = new Random(seed);
r.nextDouble();

and the standard Math.random() would not be affected. In Python, the best solution that I can see is:

old_state = random.getstate()
random.seed(seed)
random.random()
random.setstate(old_state)

Is this idiomatic Python? It seems much less clean than the Java solution that doesn’t require “restoring” an old seed. I’d love to know if there’s a better way to do this.

Answer 1

You can instantiate your own Random object.

myrandom = random.Random(myseed)

The random module manages its own instance of Random, which will be unaffected by changes made to myrandom.