shouldn't block() re-seed every time it is called?

[lungsi]

Python 2.7 with pip install csa

Based on what I understand block() changes seed every time it is evoked so for

this results in the above.

However, for the same probability of success, here r = random(0.5) if we evoke block of the same size

and again

and so on ...

If block() re-seeds every time it is called, should all of the above look exactly the same?

PS: This issue is persistent also for python 3.7

[sanchalitorpe-source]

The observed behavior is expected.

block() does not re-seed the random number generator each time it is called. It uses the current RNG state, and each call advances that state.

Because of this, repeated calls with the same probability (e.g. r = random(0.5)) and the same block size will produce different realizations, even though the probability of success is identical.

If block() were to re-seed on every call, all results would look identical, which would be undesirable for stochastic simulations.
For reproducible results, the RNG must be explicitly seeded by the user (e.g. random.seed(42)) or passed in as a parameter if supported.

This seems to be a documentation/expectation issue rather than a bug, and it may help to clarify this behavior in the docs or function docstring.