Seed the PRNG: --seed N, default random, printed for reproducibility - #7
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Seed the PRNG: --seed N, default random, printed for reproducibility#7spinkham wants to merge 1 commit into
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…ility) rand() was never seeded, so every pathsim invocation produced bit-identical fading and noise (verified byte-identical across separate process runs): N runs intended as independent Monte-Carlo trials replay one realization N times, silently. Seed from std::random_device by default, accept --seed N for exact reproduction, and print the seed used to stderr (stderr so a future stdout streaming mode stays clean). Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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rand()is never seeded anywhere in the tree, so it runs from C's default seed and every pathsim invocation produces bit-identical fading and noise — verified byte-identical output across separate process runs. Anyone running the simulator N times to gather fade-ensemble statistics (BER curves, modem robustness trials) gets one realization replayed N times, silently.This adds a
--seed Noption:std::random_deviceseed, so back-to-back runs are independent trials;--seed.Verified (on master + the
<cstring>build fix from #6, needed to compile on modern GCC):One commit, ~15 lines, no change to any DSP path — only when the shared PRNG is seeded.
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