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Complexitylib.Algebraic.LowerBound.Cutwidth.Extractor.Strong.OneShot.Weighted

One-shot extraction from nonuniform finite sources #

The actual program extracts ell bits with error 2^(-e) from every normalized source whose point masses are at most 2^(-(ell+2*e)). Sources may be represented by any injective encoding into n-bit words; the direct Boolean-vector instance needs no supplied encoding. Both seeds remain in every statistical test.

Only the statistical guarantee is extended. The program and its previously checked uniform polynomial-time certificate are the same as for flat sources. The mixture proof does not require sampling or computing the source probabilities.

theorem Algebraic.Cutwidth.Extractor.decodedOneShotExtractor_weightedStrongSeededExtractor (n ell e : ℕ) {α : Type u_1} [Fintype α] [Fintype (AdjoinRoot (binaryModulus (oneShotCondenserExponent n ell e)))] [Fintype (AdjoinRoot (binaryModulus (oneShotHashExponent n ell e)))] (input : α ↪ List Bool) (source : ∀ (x : α), (input x).length = n) :
WeightedStrongSeededExtractor (fun (x : α) => decodedOneShotExtractor n ell e (input x)) (2 ^ (ell + 2 * e)) (2 ^ e)⁻¹

The actual one-shot program strongly extracts from every capped finite source with an injective fixed-length bit encoding.

In particular, all normalized capped distributions on n Boolean coordinates satisfy the one-shot guarantee at the same parameters.