Safe Haskell	None
Language	Haskell2010

DataFrame.Internal.Simplify

Contents

Path-condition entailment (for fitted-tree pruning)

Synopsis

simplify :: Columnable a => Expr a -> Expr a
simplifyPredicatePair :: Columnable a => Bool -> Expr a -> Expr a -> Maybe (Expr a)
data PredFact
factTrue :: Expr Bool -> Maybe PredFact
factFalse :: Expr Bool -> Maybe PredFact
entails :: [PredFact] -> Expr Bool -> Maybe Bool

Documentation

simplify :: Columnable a => Expr a -> Expr a Source #

simplifyPredicatePair :: Columnable a => Bool -> Expr a -> Expr a -> Maybe (Expr a) Source #

Path-condition entailment (for fitted-tree pruning)

data PredFact Source #

A known same-column threshold fact accumulated along a tree path.

factTrue :: Expr Bool -> Maybe PredFact Source #

The fact a branch's true edge establishes (the condition holds).

factFalse :: Expr Bool -> Maybe PredFact Source #

The fact a branch's false edge establishes (the negated condition). Only sound for non-NaN (integral) columns — a NaN row takes the false edge too, so ¬(x>t) is not a clean x<=t bound for floats.

entails :: [PredFact] -> Expr Bool -> Maybe Bool Source #

entails facts cond: Just True when the path facts force cond true, Just False when they force it false, Nothing when undecided.