feat: add metrics dot and cos (#566)

* feat: add metrics dot and cos

Signed-off-by: cutecutecat <junyuchen@tensorchord.ai>

* add option residual_quantization

Signed-off-by: cutecutecat <junyuchen@tensorchord.ai>

* deprecate residual except l2

Signed-off-by: cutecutecat <junyuchen@tensorchord.ai>

* fix by comments

Signed-off-by: cutecutecat <junyuchen@tensorchord.ai>

---------

Signed-off-by: cutecutecat <junyuchen@tensorchord.ai>

Author: cutecutecat

crates/base/src/index.rs

@@ -149,9 +149,9 @@ impl IndexOptions {
                 }
             }
             IndexingOptions::Rabitq(_) => {
-                if !matches!(self.vector.d, DistanceKind::L2) {
+                if !matches!(self.vector.d, DistanceKind::L2 | DistanceKind::Dot) {
                     return Err(ValidationError::new(
-                        "rabitq is not support for distance that is not l2",
+                        "rabitq is not support for distance that is not l2 or dot",
                     ));
                 }
                 if !matches!(self.vector.v, VectorKind::Vecf32) {
@@ -446,8 +446,10 @@ pub struct RabitqIndexingOptions {
     #[serde(default = "RabitqIndexingOptions::default_nlist")]
     #[validate(range(min = 1, max = 1_000_000))]
     pub nlist: u32,
-    #[serde(default = "IvfIndexingOptions::default_spherical_centroids")]
+    #[serde(default = "RabitqIndexingOptions::default_spherical_centroids")]
     pub spherical_centroids: bool,
+    #[serde(default = "RabitqIndexingOptions::default_residual_quantization")]
+    pub residual_quantization: bool,
 }
 
 impl RabitqIndexingOptions {
@@ -457,13 +459,17 @@ impl RabitqIndexingOptions {
     fn default_spherical_centroids() -> bool {
         false
     }
+    fn default_residual_quantization() -> bool {
+        false
+    }
 }
 
 impl Default for RabitqIndexingOptions {
     fn default() -> Self {
         Self {
             nlist: Self::default_nlist(),
             spherical_centroids: Self::default_spherical_centroids(),
+            residual_quantization: Self::default_residual_quantization(),
         }
     }
 }

crates/rabitq/src/lib.rs

@@ -31,6 +31,7 @@ pub struct Rabitq<O: Op> {
     offsets: Json<Vec<u32>>,
     projected_centroids: Json<Vec2<f32>>,
     projection: Json<Vec<Vec<f32>>>,
+    is_residual: Json<bool>,
 }
 
 impl<O: Op> Rabitq<O> {
@@ -74,21 +75,16 @@ impl<O: Op> Rabitq<O> {
             opts.rabitq_nprobe as usize,
         );
         let mut heap = Vec::new();
-        for &(_, i) in lists.iter() {
+        for &(dis_v2, i) in lists.iter() {
+            let trans_vector = if *self.is_residual {
+                &O::residual(&projected_query, &self.projected_centroids[(i,)])
+            } else {
+                &projected_query
+            };
             let preprocessed = if opts.rabitq_fast_scan {
-                self.quantization
-                    .fscan_preprocess(&O::residual(
-                        &projected_query,
-                        &self.projected_centroids[(i,)],
-                    ))
-                    .into()
+                self.quantization.fscan_preprocess(trans_vector, dis_v2)
             } else {
-                self.quantization
-                    .preprocess(&O::residual(
-                        &projected_query,
-                        &self.projected_centroids[(i,)],
-                    ))
-                    .into()
+                self.quantization.preprocess(trans_vector, dis_v2)
             };
             let start = self.offsets[i];
             let end = self.offsets[i + 1];
@@ -116,6 +112,7 @@ fn from_nothing<O: Op>(
     let RabitqIndexingOptions {
         nlist,
         spherical_centroids,
+        residual_quantization,
     } = options.indexing.clone().unwrap_rabitq();
     let projection = {
         use nalgebra::{DMatrix, QR};
@@ -137,6 +134,7 @@ fn from_nothing<O: Op>(
         }
         projection
     };
+    let is_residual = residual_quantization && O::SUPPORT_RESIDUAL;
     rayon::check();
     let samples = O::sample(collection, nlist);
     rayon::check();
@@ -174,16 +172,30 @@ fn from_nothing<O: Op>(
     let collection = RemappedCollection::from_collection(collection, remap);
     rayon::check();
     let storage = O::Storage::create(path.as_ref().join("storage"), &collection);
-    let quantization = Quantization::create(
-        path.as_ref().join("quantization"),
-        options.vector,
-        collection.len(),
-        |vector| {
-            let vector = O::cast(collection.vector(vector));
-            let target = k_means_lookup(vector, &centroids);
-            O::proj(&projection, &O::residual(vector, &centroids[(target,)]))
-        },
-    );
+
+    let quantization = if is_residual {
+        Quantization::create(
+            path.as_ref().join("quantization"),
+            options.vector,
+            collection.len(),
+            |vector| {
+                let vector = O::cast(collection.vector(vector));
+                let target = k_means_lookup(vector, &centroids);
+                O::proj(&projection, &O::residual(vector, &centroids[(target,)]))
+            },
+        )
+    } else {
+        Quantization::create(
+            path.as_ref().join("quantization"),
+            options.vector,
+            collection.len(),
+            |vector| {
+                let vector = O::cast(collection.vector(vector));
+                O::proj(&projection, vector)
+            },
+        )
+    };
+
     let projected_centroids = Vec2::from_vec(
         (centroids.shape_0(), centroids.shape_1()),
         (0..centroids.shape_0())
@@ -200,13 +212,15 @@ fn from_nothing<O: Op>(
         projected_centroids,
     );
     let projection = Json::create(path.as_ref().join("projection"), projection);
+    let is_residual = Json::create(path.as_ref().join("is_residual"), is_residual);
     Rabitq {
         storage,
         payloads,
         offsets,
         projected_centroids,
         quantization,
         projection,
+        is_residual,
     }
 }
 
@@ -217,17 +231,19 @@ fn open<O: Op>(path: impl AsRef<Path>) -> Rabitq<O> {
     let offsets = Json::open(path.as_ref().join("offsets"));
     let projected_centroids = Json::open(path.as_ref().join("projected_centroids"));
     let projection = Json::open(path.as_ref().join("projection"));
+    let is_residual = Json::open(path.as_ref().join("is_residual"));
     Rabitq {
         storage,
         quantization,
         payloads,
         offsets,
         projected_centroids,
         projection,
+        is_residual,
     }
 }
 
-fn select(mut lists: Vec<(f32, usize)>, n: usize) -> Vec<(f32, usize)> {
+fn select<T>(mut lists: Vec<(f32, T)>, n: usize) -> Vec<(f32, T)> {
     if lists.is_empty() || n == 0 {
         return Vec::new();
     }