More code refactorings

Author: Sergio0694

NeuralNetwork.NET/Extensions/SpanExtensions.cs

@@ -1,5 +1,4 @@
 using System;
-using System.Runtime.CompilerServices;
 using System.Threading.Tasks;
 using JetBrains.Annotations;
 
@@ -30,14 +29,14 @@ public static unsafe void Fill<T>(this Span<T> span, [NotNull] Func<T> provider)
                 Parallel.For(0, cores, i =>
                 {
                     T* p = pc + i * batch;
-                    for (int j = 0; j < batch; j++, p++)
-                        Unsafe.Write(p, provider());
+                    for (int j = 0; j < batch; j++)
+                        p[j] = provider();
                 }).AssertCompleted();
 
                 // Remaining values
                 if (mod < 1) return;
                 for (int i = span.Length - mod; i < span.Length; i++)
-                    Unsafe.Write(pc + i, provider());
+                    pc[i] = provider();
             }
         }
 
@@ -72,7 +71,7 @@ public static unsafe int GetContentHashCode<T>(this Span<T> span) where T : unma
                 unchecked
                 {
                     for (int i = 0; i < span.Length; i++)
-                        hash = hash * 23 + Unsafe.Read<T>(p0 + i).GetHashCode();
+                        hash = hash * 23 + p0[i].GetHashCode();
                     return hash;
                 }
             }

NeuralNetwork.NET/SupervisedLearning/Data/BatchesCollection.cs

@@ -68,16 +68,21 @@ public int BatchSize
         public long ByteSize => sizeof(float) * Count * (InputFeatures + OutputFeatures);
 
         /// <inheritdoc/>
-        public int Id
+        public unsafe int Id
         {
             get
             {
                 int[] temp = new int[Count];
+                int
+                    wx = InputFeatures,
+                    wy = OutputFeatures;
                 Parallel.For(0, Count, i =>
                 {
                     ref readonly SamplesBatch batch = ref Batches[i / BatchSize];
                     int offset = i % BatchSize;
-                    temp[i] = batch.X.Slice(offset).GetContentHashCode() ^ batch.Y.Slice(offset).GetContentHashCode();
+                    fixed (float* px = batch.X, py = batch.Y)
+                        temp[i] = new Span<float>(px + offset * wx, wx).GetContentHashCode() ^ 
+                                  new Span<float>(py + offset * wy, wy).GetContentHashCode();
                 }).AssertCompleted();
                 Array.Sort(temp);
                 return temp.AsSpan().GetContentHashCode();

NeuralNetwork.NET/SupervisedLearning/Parameters/DatasetBase.cs

@@ -43,12 +43,22 @@ public DatasetSample this[int i]
         }
 
         /// <inheritdoc/>
-        public int Id
+        public unsafe int Id
         {
             get
             {
                 int[] temp = new int[Count];
-                Parallel.For(0, Count, i => temp[i] = Dataset.X.Slice(i).GetContentHashCode() ^ Dataset.Y.Slice(i).GetContentHashCode()).AssertCompleted();
+                int
+                    wx = Dataset.X.GetLength(1),
+                    wy = Dataset.Y.GetLength(1);
+                fixed (float* px0 = Dataset.X, py0 = Dataset.Y)
+                {
+                    float* px = px0, py = py0;
+                    Parallel.For(0, Count, i =>
+                    {
+                        temp[i] = new Span<float>(px + i * wx, wx).GetContentHashCode() ^ new Span<float>(py + i * wy, wy).GetContentHashCode();
+                    }).AssertCompleted();
+                }
                 Array.Sort(temp);
                 return temp.AsSpan().GetContentHashCode();
             }