From 604475023300e3947b28de5cb514d1c913313e29 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Cl=C3=A9ment=20Renault?= <clement@meilisearch.com>
Date: Wed, 13 Dec 2023 17:23:20 +0100
Subject: [PATCH 1/3] Fix the angular distance

---
 src/distance/angular.rs | 24 +++++++++++++++---------
 1 file changed, 15 insertions(+), 9 deletions(-)

diff --git a/src/distance/angular.rs b/src/distance/angular.rs
index 1616a7f7..c610b5bd 100644
--- a/src/distance/angular.rs
+++ b/src/distance/angular.rs
@@ -34,19 +34,25 @@ impl Distance for Angular {
     }
 
     fn built_distance(p: &Leaf<Self>, q: &Leaf<Self>) -> f32 {
-        let pp = p.header.norm;
-        let qq = q.header.norm;
+        let pn = p.header.norm;
+        let qn = q.header.norm;
         let pq = dot_product(&p.vector, &q.vector);
-        let ppqq = pp * qq;
-        if ppqq >= f32::MIN_POSITIVE {
-            2.0 - 2.0 * pq / ppqq.sqrt()
-        } else {
-            2.0 // cos is 0
-        }
+        let pnqn = pn * qn;
+        let cos = pq / pnqn;
+
+        // cos is [-1; 1]
+        // cos =  0. -> 0.5
+        // cos = -1. -> 1.0
+        // cos =  1. -> 0.0
+        (1.0 - cos) / 2.0
+    }
+
+    fn normalized_distance(d: f32) -> f32 {
+        d
     }
 
     fn init(node: &mut Leaf<Self>) {
-        node.header.norm = dot_product(&node.vector, &node.vector);
+        node.header.norm = dot_product(&node.vector, &node.vector).sqrt();
     }
 
     fn create_split<R: Rng>(

From 7cada5918bdb5cac8c1192e6bca776c7c077adef Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Cl=C3=A9ment=20Renault?= <clement@meilisearch.com>
Date: Wed, 13 Dec 2023 17:28:39 +0100
Subject: [PATCH 2/3] Fix the windows CI

---
 .github/workflows/rust.yml | 2 +-
 src/parallel.rs            | 5 +++--
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/.github/workflows/rust.yml b/.github/workflows/rust.yml
index e04bae8d..02ea113f 100644
--- a/.github/workflows/rust.yml
+++ b/.github/workflows/rust.yml
@@ -11,7 +11,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        os: [ubuntu-latest, macos-latest-xlarge]
+        os: [ubuntu-latest, macos-latest-xlarge, windows-latest]
         rust:
           - stable
           - beta
diff --git a/src/parallel.rs b/src/parallel.rs
index 3b722073..c6698688 100644
--- a/src/parallel.rs
+++ b/src/parallel.rs
@@ -7,7 +7,7 @@ use std::sync::atomic::{AtomicU64, Ordering};
 
 use heed::types::Bytes;
 use heed::{BytesDecode, BytesEncode, RoTxn};
-use memmap2::{Advice, Mmap};
+use memmap2::Mmap;
 use rand::seq::index;
 use rand::Rng;
 use roaring::RoaringBitmap;
@@ -64,7 +64,8 @@ impl<'a, DE: BytesEncode<'a>> TmpNodes<DE> {
     pub fn into_bytes_reader(self) -> Result<TmpNodesReader> {
         let file = self.file.into_inner().map_err(|iie| iie.into_error())?;
         let mmap = unsafe { Mmap::map(&file)? };
-        mmap.advise(Advice::Sequential)?;
+        #[cfg(unix)]
+        mmap.advise(memmap2::Advice::Sequential)?;
         Ok(TmpNodesReader { mmap, ids: self.ids, bounds: self.bounds })
     }
 }

From a73cf33a3f1dfd4043862345474df6bdd7309c83 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Cl=C3=A9ment=20Renault?= <clement@meilisearch.com>
Date: Wed, 13 Dec 2023 17:56:15 +0100
Subject: [PATCH 3/3] Make sure not to divide by zero

---
 src/distance/angular.rs | 17 ++++++++++-------
 1 file changed, 10 insertions(+), 7 deletions(-)

diff --git a/src/distance/angular.rs b/src/distance/angular.rs
index c610b5bd..b0d93d8f 100644
--- a/src/distance/angular.rs
+++ b/src/distance/angular.rs
@@ -38,13 +38,16 @@ impl Distance for Angular {
         let qn = q.header.norm;
         let pq = dot_product(&p.vector, &q.vector);
         let pnqn = pn * qn;
-        let cos = pq / pnqn;
-
-        // cos is [-1; 1]
-        // cos =  0. -> 0.5
-        // cos = -1. -> 1.0
-        // cos =  1. -> 0.0
-        (1.0 - cos) / 2.0
+        if pnqn != 0.0 {
+            let cos = pq / pnqn;
+            // cos is [-1; 1]
+            // cos =  0. -> 0.5
+            // cos = -1. -> 1.0
+            // cos =  1. -> 0.0
+            (1.0 - cos) / 2.0
+        } else {
+            0.0
+        }
     }
 
     fn normalized_distance(d: f32) -> f32 {