stilt.config.VariantConfig.setup_seed

static VariantConfig.setup_seed(seed)

Return the SEED value written to SETUP.CFG for a user seed.

HYSPLIT sets its generator state to -1 + SEED. Under krand=2 it reinitializes only from a negative state, and every state of -1 or more gives the same stream. Writing -(|seed| + 1) puts the state at -(|seed| + 2). That is negative, different for each |seed|, and never the unseeded default (SEED = 0). A patched HYSPLIT that uses SEED directly maps a negative SEED to the same state, so the value works with both builds.

Return type:

int

Parameters:

seed (int)