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Shot sampler assigns boundary uniforms to the earlier outcome · case 05

u = 0 selects an outcome with zero weight, and u exactly on a cumulative edge lands in the lower bucket.

Member previewVariant 5 · 3 implementations · 7 checks per implementation

Case contract

Input [n, weights, uniforms]; weights are nonnegative integers for basis indices 0..2**n-1 and uniforms are exact decimal or fraction strings in [0, 1). Each uniform u selects the first index i with u * total < cumulative weight through i. Return counts {bitstring: count} with qubit n-1 leftmost. Errors: "bad-length", "negative-weight", "no-support", ["bad-uniform", position].

Why this case matters

Deterministic replay of sampled shots makes simulator results reproducible; CDF boundary slips bias counts toward impossible outcomes.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
regression: random shots 30	`{"000": 2, "010": 1, "011": 2, "101": 1}`	`{"001": 2, "010": 1, "011": 1, "101": 2}`	Failed

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