feat: LLamaSharp embeddings and test (#47)

* updated LLamaSharp to 0.7, updated examples

* LLamaSharp embeddings and test

src/libs/Providers/LangChain.Providers.LLamaSharp/LLamaSharpEmbeddings.cs

@@ -0,0 +1,41 @@
+using LangChain.Abstractions.Embeddings.Base;
+using LLama.Common;
+using LLama;
+
+namespace LangChain.Providers.LLamaSharp;
+
+public class LLamaSharpEmbeddings:IEmbeddings
+{
+    protected readonly LLamaSharpConfiguration _configuration;
+    protected readonly LLamaWeights _model;
+    protected readonly ModelParams _parameters;
+    private readonly LLamaEmbedder _embedder;
+
+    public LLamaSharpEmbeddings(LLamaSharpConfiguration configuration)
+    {
+        _parameters = new ModelParams(configuration.PathToModelFile)
+        {
+            ContextSize = (uint)configuration.ContextSize,
+            Seed = (uint)configuration.Seed,
+
+        };
+        _model = LLamaWeights.LoadFromFile(_parameters);
+        _configuration = configuration;
+        _embedder = new LLamaEmbedder(_model, _parameters);
+    }
+
+    public Task<float[][]> EmbedDocumentsAsync(string[] texts, CancellationToken cancellationToken = default)
+    {
+        float[][] result = new float[texts.Length][];
+        for (int i = 0; i < texts.Length; i++)
+        {
+            result[i] = _embedder.GetEmbeddings(texts[i]);
+        }
+        return Task.FromResult(result);
+    }
+
+    public Task<float[]> EmbedQueryAsync(string text, CancellationToken cancellationToken = default)
+    {
+        return Task.FromResult(_embedder.GetEmbeddings(text));
+    }
+}

src/tests/LangChain.Providers.LLamaSharp.IntegrationTests/LLamaSharpTests.cs

@@ -54,4 +54,49 @@ public void InstructionTest()
         Assert.AreEqual("4",response.Messages.Last().Content.Trim());
 
     }
+
+    float VectorDistance(float[] a, float[] b)
+    {
+        float result = 0;
+        for (int i = 0; i < a.Length; i++)
+        {
+            result += (a[i] - b[i]) * (a[i] - b[i]);
+        }
+
+        return result;
+
+    }
+    [TestMethod]
+#if CONTINUOUS_INTEGRATION_BUILD
+    [Ignore]
+#endif
+    public void EmbeddingsTest()
+    {
+        var model = new LLamaSharpEmbeddings(new LLamaSharpConfiguration
+        {
+            PathToModelFile = ModelPath,
+            Temperature = 0
+        });
+
+        string[] texts = new string[]
+        {
+            "I spent entire day watching TV",
+            "My dog name is Bob",
+            "This icecream is delicious",
+            "It is cold in space"
+        };
+
+        var database = model.EmbedDocumentsAsync(texts).Result;
+
+
+        var query = model.EmbedQueryAsync("How do you call your pet?").Result;
+
+        var zipped = database.Zip(texts);
+
+        var ordered= zipped.Select(x=>new {text=x.Second,dist=VectorDistance(x.First,query)});
+
+        var closest = ordered.OrderBy(x => x.dist).First();
+
+        Assert.AreEqual("My dog name is Bob", closest.text);
+    }
 }