Which compounds give a yellow precipitate of iodoform on warming with $\mathrm{I}{}_2$ and $\mathrm{NaOH}$?

The iodoform test needs a $\mathrm{CH}{}_3-\mathrm{CO}{}^{-}$ group or a $\mathrm{CH}{}_3-\mathrm{CH}(\mathrm{OH}){}^{-}$ group, since hypoiodite first oxidises the latter to the methyl ketone (ethanol goes via ethanal). Ethanol and 1-phenylethanol qualify. Butan-1-ol and pentan-3-one contain neither group.