Added Equals and GetHashCode methods to SparseVector

src/Pgvector/SparseVector.cs

@@ -105,4 +105,32 @@ public float[] ToArray()
 
         return result;
     }
+
+    public bool Equals(SparseVector? other)
+        => other is not null && Dimensions == other.Dimensions && Indices.Span.SequenceEqual(other.Indices.Span) && Values.Span.SequenceEqual(other.Values.Span);
+
+    public override bool Equals(object? obj)
+        => obj is SparseVector vector && Equals(vector);
+
+    public static bool operator ==(SparseVector? x, SparseVector? y)
+        => (x is null && y is null) || (x is not null && x.Equals(y));
+
+    public static bool operator !=(SparseVector? x, SparseVector? y) => !(x == y);
+
+    public override int GetHashCode()
+    {
+        var hashCode = new HashCode();
+
+        hashCode.Add(Dimensions);
+
+        var indices = Indices.Span;
+        for (var i = 0; i < indices.Length; i++)
+            hashCode.Add(indices[i]);
+
+        var values = Values.Span;
+        for (var i = 0; i < values.Length; i++)
+            hashCode.Add(values[i]);
+
+        return hashCode.ToHashCode();
+    }
 }

tests/Pgvector.CSharp.Tests/SparseVectorTests.cs

@@ -31,4 +31,25 @@ public void DictionaryConstructor()
         Assert.Equal(new float[] { 1, 0, 2, 0, 3, 0 }, v.ToArray());
         Assert.Equal(new int[] { 0, 2, 4 }, v.Indices.ToArray());
     }
+
+    [Fact]
+    public void Equal()
+    {
+        var a = new SparseVector(new float[] { 1, 1, 1 });
+        var b = new SparseVector(new float[] { 1, 1, 1 });
+        var c = new SparseVector(new float[] { 1, 2, 3 });
+
+        Assert.Equal(a, b);
+        Assert.NotEqual(a, c);
+
+        Assert.True(a == b);
+        Assert.False(a == c);
+
+        Assert.False(a != b);
+        Assert.True(a != c);
+
+        Assert.False(a == null);
+        Assert.False(null == a);
+        Assert.True((Vector?)null == null);
+    }
 }