Misleading documentation for tableFromIntWeights

[mitchellwrosen]

createSystemRandom >>= genFromTable (tableFromIntWeights (fromList [('a',1), ('b',2)]))

This hangs for some reason, but only on lists of 2+ elements. Singleton lists return immediately.

[Shimuuar]

It's not a bug actually. Weights should add up to 2^32

-- | Generate a condensed lookup table from integer weights. Weights
-- should sum to @2^32@. If they don't, the algorithm will alter the
-- weights so that they do. This approach should work reasonably well
-- for rounding errors.

Algorithm tries to bring sum up to 2^32 but it's slow since it was created to account for rounding errors when converting from double weights to exact integral weights

[mitchellwrosen]

I think this line is misleading, then.

If they don't, the algorithm will alter the weights so that they do.

It's surprising that scaling the given weights would be slow.

[Shimuuar]

Yes I agree. Current algorithm will take ≈2^32 step and I think will produce grossly wrong answer. It could only fix small deviations from 2^32

I reopened issue and changed title