Test Improvement

src/Utils/Helpers/LinqHelper.cs

@@ -20,7 +20,7 @@ public static class LinqHelper
     /// </summary>
     public static IEnumerable<T> Shuffle<T>(this IEnumerable<T> a)
     {
-        return a.OrderBy(_ => RandomSource.Rnd.NextDouble());
+        return a.OrderBy(_ => RandomSource.Get());
     }
 
     /// <summary>
@@ -62,7 +62,7 @@ public static class LinqHelper
         T[] ac = a.ToArray();
         int len = ac.Length;
         for (int i = 0; i <= count; i++)
-            yield return ac[RandomSource.Rnd.NextInt64(0, len)];
+            yield return ac[RandomSource.Rnd.Value.NextInt64(0, len)];
     }
 
     /// <summary>
@@ -70,7 +70,7 @@ public static class LinqHelper
     /// </summary>
     public static IEnumerable<T> Sample<T>(this IEnumerable<T> a, double freq)
     {
-        return a.Where(x => RandomSource.Rnd.NextDouble() < freq);
+        return a.Where(x => RandomSource.Rnd.Value.NextDouble() < freq);
     }
 
     /// <summary>
@@ -559,6 +559,12 @@ public static class LinqHelper
     public static CategoryOf<TDim>.FSpecialLieUnitaryMatrix SpLieSum<TDim>
         (this IEnumerable<CategoryOf<TDim>.FSpecialLieUnitaryMatrix> es) =>
         new(es.LieSum());
+    public static T WithSeed<T>(this T a, int seed)
+    {
+        RandomSource.SetSeed(seed);
+        if (seed < 0)
+            RandomSource.Rnd.Value = new Random();
 
-
+        return a;
+    }
 }

src/Utils/RandomEngines/RandomSource.cs

@@ -1,3 +1,5 @@
+using Skeleton.DataStructure;
+
 namespace Skeleton.Utils.RandomEngines;
 
 /// <summary>
@@ -6,13 +8,21 @@ public static class RandomSource
 {
     /// <summary>
     /// </summary>
-    public static Random Rnd = new();
+    public static ThreadLocal<Random> Rnd = new(() => new Random());
+    
+    public static void SetSeed(int seed)
+    {
+        Rnd.Value = new Random(seed);
+    }
 
     /// <summary>
     /// </summary>
     /// <returns></returns>
     public static double Get()
     {
-        return Rnd.NextDouble();
+        return Rnd.Value.NextDouble();
     }
+    
+    
+    
 }