Tests: User-defined Matrix/Vector now copy provided array in ctor, fixing failing LA Permutation unit tests

src/Numerics/LinearAlgebra/Double/Matrix.cs

@@ -1498,7 +1498,7 @@ namespace MathNet.Numerics.LinearAlgebra.Double
             // Get a sequence of inversions from the permutation.
             var inv = p.ToInversions();
 
-            for (var i = 0; i < p.Dimension; i++)
+            for (var i = 0; i < inv.Length; i++)
             {
                 if (inv[i] != i)
                 {
@@ -1527,7 +1527,7 @@ namespace MathNet.Numerics.LinearAlgebra.Double
             // Get a sequence of inversions from the permutation.
             var inv = p.ToInversions();
 
-            for (var i = 0; i < p.Dimension; i++)
+            for (var i = 0; i < inv.Length; i++)
             {
                 if (inv[i] != i)
                 {

src/UnitTests/LinearAlgebraTests/Double/UserDefinedMatrixTests.cs

@@ -43,7 +43,7 @@ namespace MathNet.Numerics.UnitTests.LinearAlgebraTests.Double
 
         public UserDefinedMatrix(double[,] data) : base(data.GetLength(0), data.GetLength(1))
         {
-            _data = data;
+            _data = (double[,])data.Clone();
         }
 
         public override double At(int row, int column)

src/UnitTests/LinearAlgebraTests/Double/UserDefinedVectorTests.cs

@@ -46,7 +46,7 @@ namespace MathNet.Numerics.UnitTests.LinearAlgebraTests.Double
         public UserDefinedVector(double[] data)
             : base(data.Length)
         {
-            _data = data;
+            _data = (double[])data.Clone();
         }
 
         public override double this[int index]