Use ngram matching ratios in ranking instead of arbitrary function

Cloogle/DB.dcl

@@ -68,11 +68,12 @@ NGRAMS_CI :== True
  * Annotations to store during search.
  */
 :: Annotation
-	= NGramDistance !Int //* For name search, the distance based on the number of matching ngrams
-	| Unifier !Unifier   //* For type search, the unifier
+	= MatchingNGramsQuery !Real  //* The number of matching ngrams in the query
+	| MatchingNGramsResult !Real //* The number of matching ngrams in the result
+	| Unifier !Unifier  //* For type search, the unifier
 	| RequiredContext !(Maybe [(String,[LocationResult])]) //* For type search, context after unification
-	| UsedSynonyms !Int  //* The number of synonyms used for unification
-	| ExactResult        //* If this was an exact match found with filterExactName
+	| UsedSynonyms !Int //* The number of synonyms used for unification
+	| ExactResult       //* If this was an exact match found with filterExactName
 
 /**
  * Wrapper around different kinds of entries to store all in one database.

Cloogle/DB.icl

@@ -21,7 +21,7 @@ from Data.Func import $, on, `on`, mapSt
 import Data.Functor
 import Data.GenLexOrd
 import Data.Graphviz
-from Data.List import concatMap, groupBy, intercalate, intersect,
+from Data.List import concatMap, groupBy, intercalate, intersect, partition,
 	tails, instance Functor [], instance Foldable []
 from Data.Map import :: Map(..), elems, filterWithKey, foldrNoKey,
 	foldrWithKey, fromList, get, mapSize, alter, mapWithKey, newMap, put,
@@ -391,9 +391,15 @@ where
 	getIndexWithDistance idx n db
 	# (e,db) = 'DB'.getIndex idx db
 	# name = getName $ fromJust $ getLocation e.value
-	= ((idx, [NGramDistance (0 - toInt (100.0 * toReal n ^ 2.0 / toReal (size name)))]), db)
+	# rn = toReal n
+	# annots =
+		[ MatchingNGramsQuery  (rn / qsize)
+		, MatchingNGramsResult (rn / toReal (length $ 'NGrams'.ngrams NGRAMS_CI NGRAMS_N name))
+		]
+	= ((idx, annots), db)
 
 	cs = [c \\ c <-: s]
+	qsize = toReal $ length $ 'NGrams'.ngrams NGRAMS_CI NGRAMS_N s
 
 	syntaxSearch :: CloogleEntry -> (Bool, [a])
 	syntaxSearch (SyntaxEntry se) = (any (not o isEmpty o flip match cs) se.syntax_patterns, [])
@@ -526,9 +532,14 @@ where
 	where
 		updateAnnots :: ![Annotation] ![Annotation] -> [Annotation]
 		updateAnnots [] m = m
-		updateAnnots [a=:NGramDistance _:as] m = updateAnnots as [a:[a \\ a <- m | not (a=:NGramDistance _)]]
-		updateAnnots [a=:Unifier _:as]       m = updateAnnots as [a:[a \\ a <- m | not (a=:Unifier _)]]
-		updateAnnots [a=:ExactResult:as]     m = updateAnnots as [a:[a \\ a <- m | not a=:ExactResult]]
+		updateAnnots [MatchingNGramsQuery r:as] m
+			= updateAnnots as [MatchingNGramsQuery $ maxList [r:[r \\ MatchingNGramsQuery r <- match]]:nomatch]
+		where (match,nomatch) = partition (\a->a=:MatchingNGramsQuery _) m
+		updateAnnots [MatchingNGramsResult r:as] m
+			= updateAnnots as [MatchingNGramsResult $ maxList [r:[r \\ MatchingNGramsResult r <- match]]:nomatch]
+		where (match,nomatch) = partition (\a->a=:MatchingNGramsResult _) m
+		updateAnnots [a=:Unifier _:as]              m = updateAnnots as [a:[a \\ a <- m | not (a=:Unifier _)]]
+		updateAnnots [a=:ExactResult:as]            m = updateAnnots as [a:[a \\ a <- m | not a=:ExactResult]]
 
 getEntries :: !*CloogleDB -> *([(CloogleEntry, [Annotation])], *CloogleDB)
 getEntries wrap=:{db}

Cloogle/Search/Rank.dcl

@@ -12,7 +12,8 @@ from Cloogle.DB import :: Annotation, :: CloogleEntry, :: CloogleDB
  * are given by this record.
  */
 :: RankSettings =
-	{ rs_ngram_distance     :: !Real //* n-gram distance
+	{ rs_matching_ngrams_q  :: !Real //* matching n-grams in the query
+	, rs_matching_ngrams_r  :: !Real //* matching n-grams in the result
 	, rs_exact_result       :: !Real //* results with an exact match
 
 	, rs_record_field       :: !Real //* record fields

Cloogle/Search/Rank.icl

@@ -28,7 +28,8 @@ import Cloogle.Search
 
 distance :: !RankSettings !CloogleEntry ![Annotation] -> Real
 distance settings entry annots = let info = symbolicDistance entry annots in
-	settings.rs_ngram_distance     * info.rs_ngram_distance +
+	settings.rs_matching_ngrams_q  * info.rs_matching_ngrams_q +
+	settings.rs_matching_ngrams_r  * info.rs_matching_ngrams_r +
 	settings.rs_exact_result       * info.rs_exact_result +
 	settings.rs_record_field       * info.rs_record_field +
 	settings.rs_constructor        * info.rs_constructor +
@@ -43,7 +44,8 @@ distance settings entry annots = let info = symbolicDistance entry annots in
 
 symbolicDistance :: !CloogleEntry ![Annotation] -> RankInformation
 symbolicDistance entry annots =
-	{ rs_ngram_distance     = case [d \\ NGramDistance d <- annots] of [d:_] -> toReal d; _ -> 0.0
+	{ rs_matching_ngrams_q  = case [r \\ MatchingNGramsQuery r <- annots] of [r:_] -> r; _ -> 0.0
+	, rs_matching_ngrams_r  = case [r \\ MatchingNGramsResult r <- annots] of [r:_] -> r; _ -> 0.0
 	, rs_exact_result       = if (isEmpty [a \\ a=:ExactResult <- annots]) 0.0 1.0
 	, rs_record_field       = if entry=:(FunctionEntry {fe_kind=RecordField}) 1.0 0.0
 	, rs_constructor        = if entry=:(FunctionEntry {fe_kind=Constructor}) 1.0 0.0
@@ -123,7 +125,8 @@ findRankSettings constraints cdb w
 | isError out = (Error "Failed to read z3 output", cdb, w)
 # out = split "\n" $ fromOk out
 # settings = findSettings out
-	{ rs_ngram_distance     = 0.0
+	{ rs_matching_ngrams_q  = 0.0
+	, rs_matching_ngrams_r  = 0.0
 	, rs_exact_result       = 0.0
 	, rs_record_field       = 0.0
 	, rs_constructor        = 0.0
@@ -144,7 +147,8 @@ where
 		# name = s % (14,size s-9) // strip off '  (define-fun ' and ' () Real'
 		# val = toReal {#c \\ c <-: v | isDigit c || c == '.' || c == '-'}
 		# rs = case name of
-			"rs_ngram_distance"     -> {rs & rs_ngram_distance    =val}
+			"rs_matching_ngrams_q"  -> {rs & rs_matching_ngrams_q =val}
+			"rs_matching_ngrams_r"  -> {rs & rs_matching_ngrams_r =val}
 			"rs_exact_result"       -> {rs & rs_exact_result      =val}
 			"rs_record_field"       -> {rs & rs_record_field      =val}
 			"rs_constructor"        -> {rs & rs_constructor       =val}
@@ -166,7 +170,8 @@ rankConstraints constraints cdb
 = (default ++ constraints,cdb)
 where
 	default =
-		[ "(declare-const rs_ngram_distance     Real)"
+		[ "(declare-const rs_matching_ngrams_q  Real)"
+		, "(declare-const rs_matching_ngrams_r  Real)"
 		, "(declare-const rs_exact_result       Real)"
 		, "(declare-const rs_record_field       Real)"
 		, "(declare-const rs_constructor        Real)"
@@ -217,7 +222,8 @@ where
 
 	formula :: !RankInformation -> String
 	formula ri = sum
-		[ "* rs_ngram_distance "     <+ ri.rs_ngram_distance
+		[ "* rs_matching_ngrams_q "  <+ ri.rs_matching_ngrams_q
+		, "* rs_matching_ngrams_r "  <+ ri.rs_matching_ngrams_r
 		, "* rs_exact_result "       <+ ri.rs_exact_result
 		, "* rs_record_field "       <+ ri.rs_record_field
 		, "* rs_constructor "        <+ ri.rs_constructor