[Nearest Neighbor] Code and basic test for nearest neighbor

src/rtree.ml

@@ -232,6 +232,16 @@ module Make (E : Envelope) (V : Value with type envelope = E.t) = struct
     | Empty -> depth
 
   let depth t = depth' t.tree 0
+(* 
+  let nearest_neighbor elem = function 
+  | Node ns -> 
+      (* let sub_sizes = List.map (fun (_, n) -> size' n) ns in
+          List.fold_left ( + ) 0 sub_sizes *)
+  | Leaf es -> 
+      let sub_sizes = List.fold_left () es in
+        List.fold_left ( + ) 0 sub_sizes
+  | Empty -> *)
+
 end
 
 module Rectangle = Rectangle

src/rtree_intf.ml

@@ -43,6 +43,9 @@ module type Value = sig
 
   val envelope : t -> envelope
   (** Given a value, calculates the envelope for it. *)
+
+  val mindist: t -> envelope -> float
+  val minmaxdist: t -> envelope -> float
 end
 
 module type Envelope = sig

test/basic.ml

@@ -10,10 +10,61 @@ module V = struct
   type envelope = Rtree.Rectangle.t
 
   let envelope i = List.assoc i !pre_made_envelopes
+
+  let mindist _p _e = 0.
+  let minmaxdist _p _e = 0.
 end
 
 module R = Rtree.Make (Rtree.Rectangle) (V)
 
+module Vp = struct
+  type t = floatarray
+
+  let t =
+    let to_array arr = Float.Array.to_list arr |> Array.of_list in
+    let of_array arr = Array.to_list arr |> Float.Array.of_list in
+    Repr.(map (array float) of_array to_array)
+
+
+  type envelope = Rtree.Rectangle.t
+
+  let envelope fa=
+    let x0 =  Array.Floatarray.get fa 0 in
+    let x1 =  Array.Floatarray.get fa 0 in
+    let y0 =  Array.Floatarray.get fa 1 in
+    let y1 =  Array.Floatarray.get fa 1 in
+    Rtree.Rectangle.v ~x0 ~y0 ~x1 ~y1
+
+  let get arr i = Array.Floatarray.get arr i 
+
+  let mindist (p:floatarray) (e:envelope) = 
+    let (x0,y0,x1,y1) = Rtree.Rectangle.coords e in 
+    let gete ind = if ind==0 then x0
+                else if ind==1 then y0 else if ind==2 then x1 else y1 in
+    let dist i = if (get p i)< (gete i) then ( gete i ) -. (get p i)*. (gete i) -. (get p i)
+              else if (get p i)>(gete (i+2)) then (get p i) -. (gete (i+2)) *. (get p i)-. (gete (i+2))
+              else 0. in
+      dist 0 +. dist 1
+
+  let minmaxdist p e = 
+    let (x0,y0,x1,y1) = Rtree.Rectangle.coords e in 
+    let gete ind = if ind==0 then x0
+                else if ind==1 then y0 else if ind==2 then x1 else y1 in
+    let rm k = if (get p k) <= ((gete k +. gete (k+2))/.2.) then (get p k)
+              else gete (k+2) in
+
+    let rM k = if (get p k) >= ((gete k +. gete (k+2))/.2.)  then (get p k)
+              else gete (k+2) in
+
+    let farthest_distance_axis i= ( get p i -. rm i) *. (get p (i) -. rm i) in 
+    let farthest_distance = farthest_distance_axis 0 +. farthest_distance_axis 1 in
+    let max_dist_axis i = farthest_distance -. (get p i -. rM i)*.(get p i  -. rM i) +. (get p i -. rM i)*.(get p i -. rM i) in
+    min (max_dist_axis 0) (max_dist_axis 1) 
+
+end
+
+module Rp = Rtree.Make (Rtree.Rectangle) (Vp)
+
 let make_random_envelope () =
   let x0 = Random.float 100. -. 50.
   and x1 = Random.float 100. -. 50.
@@ -64,6 +115,8 @@ let test_functor _ =
         type envelope = Rtree.Rectangle.t
 
         let envelope i = List.assoc i elems
+        let mindist _p _e = 0.
+        let minmaxdist _p _e = 0.
       end)
   in
   let r =
@@ -102,6 +155,8 @@ let test_lines () =
           let y0 = Float.min y1 y2 in
           let y1 = Float.max y1 y2 in
           Rtree.Rectangle.v ~x0 ~y0 ~x1 ~y1
+        let mindist _p _e = 0.
+        let minmaxdist _p _e = 0.
       end)
   in
   let l1 = { p1 = (1., 2.); p2 = (2., 3.) } in
@@ -136,6 +191,8 @@ let omt_loader () =
           let y0 = Float.min y1 y2 in
           let y1 = Float.max y1 y2 in
           Rtree.Rectangle.v ~x0 ~y0 ~x1 ~y1
+        let mindist _p _e = 0.
+        let minmaxdist _p _e = 0.
       end)
   in
   let lines =
@@ -158,6 +215,19 @@ let rectangle () =
   let r = Rtree.Rectangle.merge_many [ r1; r2 ] in
   assert (r = r3)
 
+let test_min_dist () = 
+
+  let arr = Array.Floatarray.create 2 in
+            Array.Floatarray.unsafe_set arr 0 5.;
+            Array.Floatarray.unsafe_set arr 1 5.;
+  let point = Array.Floatarray.create 2 in
+            Array.Floatarray.unsafe_set arr 0 0.;
+            Array.Floatarray.unsafe_set arr 1 0.;
+  let env = Vp.envelope arr in
+  let dist = Vp.mindist point env in
+  assert(dist = 25.)
+
+
 let test_depth () =
   let module R =
     Rtree.Make
@@ -175,6 +245,8 @@ let test_depth () =
           let y0 = Float.min y1 y2 in
           let y1 = Float.max y1 y2 in
           Rtree.Rectangle.v ~x0 ~y0 ~x1 ~y1
+        let mindist _p _e = 0.
+        let minmaxdist _p _e = 0.
       end)
   in
   let lines =
@@ -198,6 +270,7 @@ let suite =
          "omt" >:: omt_loader;
          "rect" >:: rectangle;
          "depth" >:: test_depth;
+         "min_dist" >:: test_min_dist
        ]
 
 let _ = run_test_tt_main suite

test/image.ml

@@ -19,6 +19,8 @@ module Line = struct
     let y0 = min (Gg.P2.y p1) (Gg.P2.y p2) in
     let y1 = max (Gg.P2.y p1) (Gg.P2.y p2) in
     Rtree.Rectangle.v ~x0 ~x1 ~y0 ~y1
+    let mindist _p _e = 0.
+    let minmaxdist _p _e = 0.
 end
 
 module Point = struct
@@ -38,6 +40,8 @@ module Point = struct
     let x0 = Gg.P2.x p1 in
     let y0 = Gg.P2.y p1 in
     Rtree.Rectangle.v ~x0 ~x1:x0 ~y0 ~y1:y0
+  let mindist _p _e = 0.
+  let minmaxdist _p _e = 0.
 end
 
 module R = Rtree.Make (Rtree.Rectangle) (Line)

test/persist.ml

@@ -10,6 +10,9 @@ module Line = struct
     let y0 = Float.min arr.(1) arr.(3) in
     let y1 = Float.max arr.(1) arr.(3) in
     Rtree.Rectangle.v ~x0 ~y0 ~x1 ~y1
+
+  let mindist _p _e = 0.
+  let minmaxdist _p _e = 0.
 end
 
 module R = Rtree.Make (Rtree.Rectangle) (Line)