Switched to f16 for halfvec

Author: ankane

Cargo.toml

@@ -18,7 +18,6 @@ postgres-types = { version = "0.2", default-features = false, optional = true }
 diesel = { version = "2", default-features = false, features = ["postgres"], optional = true }
 sqlx = { version = ">= 0.8, < 0.10", default-features = false, features = ["postgres"], optional = true }
 serde = { version = "1", features = ["derive"], optional = true }
-half = { version = "2", default-features = false, optional = true }
 
 [dev-dependencies]
 postgres = { version = "0.19", default-features = false }
@@ -30,7 +29,7 @@ serde_json = "1"
 
 [features]
 postgres = ["dep:postgres-types", "dep:bytes"]
-halfvec = ["dep:half"]
+halfvec = []
 
 [package.metadata.docs.rs]
 features = ["halfvec"]

src/halfvec.rs

@@ -1,5 +1,3 @@
-use half::f16;
-
 #[cfg(feature = "diesel")]
 use crate::diesel_ext::halfvec::HalfVectorType;
 
@@ -27,7 +25,7 @@ impl From<HalfVector> for Vec<f16> {
 impl HalfVector {
     /// Creates a half vector from a `f32` slice.
     pub fn from_f32_slice(slice: &[f32]) -> HalfVector {
-        HalfVector(slice.iter().map(|v| f16::from_f32(*v)).collect())
+        HalfVector(slice.iter().map(|v| *v as f16).collect())
     }
 
     /// Returns a copy of the half vector as a `Vec<f16>`.
@@ -63,19 +61,18 @@ impl HalfVector {
 #[cfg(test)]
 mod tests {
     use crate::HalfVector;
-    use half::f16;
 
     #[test]
     fn test_into() {
         let vec = HalfVector::from(vec![
-            f16::from_f32(1.0),
-            f16::from_f32(2.0),
-            f16::from_f32(3.0),
+            1.0,
+            2.0,
+            3.0,
         ]);
         let f16_vec: Vec<f16> = vec.into();
         assert_eq!(
             f16_vec,
-            vec![f16::from_f32(1.0), f16::from_f32(2.0), f16::from_f32(3.0)]
+            vec![1.0, 2.0, 3.0]
         );
     }
 
@@ -84,7 +81,7 @@ mod tests {
         let vec = HalfVector::from_f32_slice(&[1.0, 2.0, 3.0]);
         assert_eq!(
             vec.to_vec(),
-            vec![f16::from_f32(1.0), f16::from_f32(2.0), f16::from_f32(3.0)]
+            vec![1.0, 2.0, 3.0]
         );
     }
 
@@ -93,7 +90,7 @@ mod tests {
         let vec = HalfVector::from_f32_slice(&[1.0, 2.0, 3.0]);
         assert_eq!(
             vec.as_slice(),
-            &[f16::from_f32(1.0), f16::from_f32(2.0), f16::from_f32(3.0)]
+            &[1.0, 2.0, 3.0]
         );
     }
 }

src/lib.rs

@@ -1,4 +1,5 @@
 #![doc = include_str!("../README.md")]
+#![cfg_attr(feature = "halfvec", feature(f16))]
 
 mod bit;
 mod sparsevec;

src/postgres_ext/halfvec.rs

@@ -38,7 +38,6 @@ impl ToSql for HalfVector {
 #[cfg(test)]
 mod tests {
     use crate::HalfVector;
-    use half::f16;
     use postgres::binary_copy::BinaryCopyInWriter;
     use postgres::types::{Kind, Type};
     use postgres::{Client, NoTls};
@@ -74,7 +73,7 @@ mod tests {
         let res_vec: HalfVector = row.get(0);
         assert_eq!(vec, res_vec);
         assert_eq!(
-            vec![f16::from_f32(1.0), f16::from_f32(2.0), f16::from_f32(3.0)],
+            vec![1.0, 2.0, 3.0],
             res_vec.to_vec()
         );
 
@@ -110,14 +109,14 @@ mod tests {
             .copy_in("COPY postgres_half_items (embedding) FROM STDIN WITH (FORMAT BINARY)")?;
         let mut writer = BinaryCopyInWriter::new(writer, &[halfvec_type]);
         writer.write(&[&HalfVector::from(vec![
-            f16::from_f32(1.0),
-            f16::from_f32(2.0),
-            f16::from_f32(3.0),
+            1.0,
+            2.0,
+            3.0,
         ])])?;
         writer.write(&[&HalfVector::from(vec![
-            f16::from_f32(4.0),
-            f16::from_f32(5.0),
-            f16::from_f32(6.0),
+            4.0,
+            5.0,
+            6.0,
         ])])?;
         writer.finish()?;
 

src/sqlx_ext/halfvec.rs

@@ -42,7 +42,6 @@ impl PgHasArrayType for HalfVector {
 #[cfg(test)]
 mod tests {
     use crate::HalfVector;
-    use half::f16;
     use sqlx::postgres::PgPoolOptions;
     use sqlx::Row;
 
@@ -82,7 +81,7 @@ mod tests {
         let res_vec: HalfVector = row.try_get("embedding").unwrap();
         assert_eq!(vec, res_vec);
         assert_eq!(
-            vec![f16::from_f32(1.0), f16::from_f32(2.0), f16::from_f32(3.0)],
+            vec![1.0, 2.0, 3.0],
             res_vec.to_vec()
         );