Added L1Distance function for EF Core

src/Pgvector.EntityFrameworkCore/CHANGELOG.md

@@ -1,6 +1,7 @@
 ## 0.2.1 (unreleased)
 
 - Added support for compiled models
+- Added `L1Distance` function
 
 ## 0.2.0 (2023-11-24)
 

src/Pgvector.EntityFrameworkCore/VectorDbFunctionsExtensions.cs

@@ -12,4 +12,7 @@ public static double MaxInnerProduct(this Vector a, Vector b)
 
     public static double CosineDistance(this Vector a, Vector b)
         => throw new InvalidOperationException(CoreStrings.FunctionOnClient(nameof(CosineDistance)));
+
+    public static double L1Distance(this Vector a, Vector b)
+        => throw new InvalidOperationException(CoreStrings.FunctionOnClient(nameof(L1Distance)));
 }

src/Pgvector.EntityFrameworkCore/VectorDbFunctionsTranslatorPlugin.cs

@@ -49,6 +49,13 @@ private class VectorDbFunctionsTranslator : IMethodCallTranslator
                 typeof(Vector),
             })!;
 
+        private static readonly MethodInfo _methodL1Distance = typeof(VectorDbFunctionsExtensions)
+            .GetRuntimeMethod(nameof(VectorDbFunctionsExtensions.L1Distance), new[]
+            {
+                typeof(Vector),
+                typeof(Vector),
+            })!;
+
         public VectorDbFunctionsTranslator(
             ISqlExpressionFactory sqlExpressionFactory,
             IRelationalTypeMappingSource typeMappingSource
@@ -71,6 +78,7 @@ IRelationalTypeMappingSource typeMappingSource
                 _ when ReferenceEquals(method, _methodL2Distance) => "<->",
                 _ when ReferenceEquals(method, _methodMaxInnerProduct) => "<#>",
                 _ when ReferenceEquals(method, _methodCosineDistance) => "<=>",
+                _ when ReferenceEquals(method, _methodL1Distance) => "<+>",
                 _ => null
             };
 

tests/Pgvector.CSharp.Tests/EntityFrameworkCoreTests.cs

@@ -69,6 +69,9 @@ public async Task Main()
         items = await ctx.Items.OrderBy(x => x.Embedding!.CosineDistance(embedding)).Take(5).ToListAsync();
         Assert.Equal(3, items[2].Id);
 
+        items = await ctx.Items.OrderBy(x => x.Embedding!.L1Distance(embedding)).Take(5).ToListAsync();
+        Assert.Equal(new int[] { 1, 3, 2 }, items.Select(v => v.Id).ToArray());
+
         items = await ctx.Items
             .OrderBy(x => x.Id)
             .Where(x => x.Embedding!.L2Distance(embedding) < 1.5)