Release version 4.4.1

CHANGELOG.md

@@ -1,3 +1,7 @@
+### Version 4.4.1 - 2026-08-24
+
+* Fix issue with SparseLU refactorization
+
 ### Version 4.4.0 - 2026-06-10
 
 * Add Refactorize methods to SparseCholesky, SparseLDL and SparseLU

CSparse.Tests/CSparse.Tests.csproj

@@ -43,7 +43,7 @@
   <ItemGroup>
     <PackageReference Include="NUnit" Version="4.6.1" />
     <PackageReference Include="NUnit3TestAdapter" Version="6.2.0" />
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.6.0" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.9.0" />
   </ItemGroup>
 
   <ItemGroup>

CSparse/CSparse.csproj

@@ -11,17 +11,21 @@
     <Company />
     <Copyright>Copyright Christian Woltering © 2012-2026</Copyright>
     <Authors>Christian Woltering</Authors>
-    <AssemblyVersion>4.4.0.0</AssemblyVersion>
-    <FileVersion>4.4.0.0</FileVersion>
+    <AssemblyVersion>4.4.1.0</AssemblyVersion>
+    <FileVersion>4.4.1.0</FileVersion>
     <PackageTags>math sparse matrix lu cholesky qr decomposition factorization</PackageTags>
-    <Version>4.4.0</Version>
+    <Version>4.4.1</Version>
     <AssemblyName>CSparse</AssemblyName>
     <RootNamespace>CSparse</RootNamespace>
     <PackageLicenseExpression>LGPL-2.1-only</PackageLicenseExpression>
     <PackageProjectUrl>https://github.com/wo80/CSparse.NET</PackageProjectUrl>
     <RepositoryUrl>https://github.com/wo80/CSparse.NET.git</RepositoryUrl>
     <RepositoryType>git</RepositoryType>
-    <PackageReleaseNotes>Version 4.4.0
+    <PackageReleaseNotes>Version 4.4.1
+
+* Fix issue with SparseLU refactorization
+
+Version 4.4.0
 
 * Add Refactorize methods to SparseCholesky, SparseLDL and SparseLU
 

CSparse/Check.cs

@@ -8,7 +8,7 @@ static class Check
     {
         public static void NotNull(object obj, string name)
         {
-            if (obj == null)
+            if (obj is null)
             {
                 throw new ArgumentNullException(name);
             }

CSparse/Complex/DenseMatrix.cs

@@ -282,7 +282,7 @@ public override bool Equals(Matrix<Complex> other, double tolerance)
 
             var dense = other as DenseColumnMajorStorage<Complex>;
 
-            if (dense == null)
+            if (dense is null)
             {
                 return false;
             }

CSparse/Complex/Factorization/SparseCholesky.cs

@@ -195,7 +195,7 @@ private bool UpDown(int sigma, CompressedColumnStorage<Complex> w)
 
             var parent = S.parent;
 
-            if (parent == null)
+            if (parent is null)
             {
                 return false;
             }
@@ -315,10 +315,7 @@ private void Factorize(CompressedColumnStorage<Complex> A, IProgress<double> pro
                 {
                     current += step;
 
-                    if (progress != null)
-                    {
-                        progress.Report(k / (double)n);
-                    }
+                    progress?.Report(k / (double)n);
                 }
 
                 // Find nonzero pattern of L(k,:)

CSparse/Complex/Factorization/SparseLDL.cs

@@ -312,10 +312,7 @@ void Factorize(CompressedColumnStorage<Complex> A, IProgress<double> progress)
                 {
                     current += step;
 
-                    if (progress != null)
-                    {
-                        progress.Report(k / (double)n);
-                    }
+                    progress?.Report(k / (double)n);
                 }
 
                 // compute nonzero Pattern of kth row of L, in topological order

CSparse/Complex/Factorization/SparseLU.cs

@@ -134,7 +134,7 @@ public void Refactorize(CompressedColumnStorage<Complex> A, double tol = 1.0)
 
             if (A.ColumnCount != n)
             {
-                throw new ArgumentException("Matrix dimensions don't match the factorization.", "A");
+                throw new ArgumentException("Matrix dimensions don't match the factorization.", nameof(A));
             }
 
             // Ensure tol is in range.
@@ -262,10 +262,7 @@ private void Factorize(CompressedColumnStorage<Complex> A, double tol, IProgress
                 {
                     current += step;
 
-                    if (progress != null)
-                    {
-                        progress.Report(k / (double)n);
-                    }
+                    progress?.Report(k / (double)n);
                 }
 
                 // Triangular solve
@@ -381,7 +378,7 @@ private void SymbolicAnalysis(CompressedColumnStorage<Complex> A, int[] p)
         private int SolveSp(CompressedColumnStorage<Complex> G, CompressedColumnStorage<Complex> B,
             int k, int[] xi, Complex[] x, int[] pinv, bool lo)
         {
-            if (xi == null || x == null) return -1;
+            if (xi is null || x is null) return -1;
 
             var gp = G.ColumnPointers;
             var gi = G.RowIndices;

CSparse/Complex/Factorization/SparseQR.cs

@@ -208,7 +208,7 @@ protected override Complex CreateHouseholder(Complex[] x, int offset, ref double
         {
             Complex s = Complex.Zero;
             int i;
-            if (x == null) return -1; // check inputs
+            if (x is null) return -1; // check inputs
 
             // s = norm(x)
             for (i = 0; i < n; i++)
@@ -243,7 +243,7 @@ protected override bool ApplyHouseholder(CompressedColumnStorage<Complex> V, int
             int p = 0;
             Complex tau = Complex.Zero;
 
-            if (x == null) return false; // check inputs
+            if (x is null) return false; // check inputs
 
             var vp = V.ColumnPointers;
             var vi = V.RowIndices;

CSparse/Complex/SparseMatrix.cs

@@ -321,12 +321,12 @@ public override void Transpose(CompressedColumnStorage<Complex> result, bool sto
         public override void Add(Complex alpha, Complex beta, CompressedColumnStorage<Complex> other,
             CompressedColumnStorage<Complex> result)
         {
-            if (other == null)
+            if (other is null)
             {
                 throw new ArgumentNullException(nameof(other));
             }
 
-            if (result == null)
+            if (result is null)
             {
                 throw new ArgumentNullException(nameof(result));
             }
@@ -379,12 +379,12 @@ public override void Add(Complex alpha, Complex beta, CompressedColumnStorage<Co
         /// <inheritdoc />
         public override void Multiply(CompressedColumnStorage<Complex> other, CompressedColumnStorage<Complex> result)
         {
-            if (other == null)
+            if (other is null)
             {
                 throw new ArgumentNullException(nameof(other));
             }
 
-            if (result == null)
+            if (result is null)
             {
                 throw new ArgumentNullException(nameof(result));
             }
@@ -494,7 +494,7 @@ public override bool Equals(Matrix<Complex> other, double tolerance)
         {
             var o = other as SparseMatrix;
 
-            if (o == null)
+            if (o is null)
             {
                 return false;
             }
@@ -590,9 +590,9 @@ internal override int Scatter(int j, Complex beta, int[] w, Complex[] x, int mar
         {
             int i, p;
 
-            if (w == null || mat == null) return -1; // check inputs
+            if (w is null || mat is null) return -1; // check inputs
 
-            if (x == null)
+            if (x is null)
             {
                 throw new ArgumentNullException(nameof(x));
             }

CSparse/Converter.cs

@@ -302,9 +302,9 @@ public static CoordinateStorage<T> FromEnumerable<T>(IEnumerable<(int row, int c
         {
             var storage = new CoordinateStorage<T>(rowCount, columnCount, Math.Max(rowCount, columnCount));
 
-            foreach (var item in enumerable)
+            foreach (var (row, column, value) in enumerable)
             {
-                storage.At(item.row, item.column, item.value);
+                storage.At(row, column, value);
             }
 
             return storage;

CSparse/Double/DenseMatrix.cs

@@ -271,7 +271,7 @@ public override void ParallelMultiply(DenseColumnMajorStorage<double> other, Den
                 return;
             }
 
-            if (options == null)
+            if (options is null)
             {
                 options = new ParallelOptions() { MaxDegreeOfParallelism = processorCount };
             }
@@ -342,7 +342,7 @@ public override bool Equals(Matrix<double> other, double tolerance)
 
             var dense = other as DenseColumnMajorStorage<double>;
 
-            if (dense == null)
+            if (dense is null)
             {
                 return false;
             }

CSparse/Double/Factorization/SparseCholesky.cs

@@ -194,7 +194,7 @@ private bool UpDown(int sigma, CompressedColumnStorage<double> w)
 
             var parent = S.parent;
 
-            if (parent == null)
+            if (parent is null)
             {
                 return false;
             }
@@ -310,10 +310,7 @@ private void Factorize(CompressedColumnStorage<double> A, IProgress<double> prog
                 {
                     current += step;
 
-                    if (progress != null)
-                    {
-                        progress.Report(k / (double)n);
-                    }
+                    progress?.Report(k / (double)n);
                 }
 
                 // Find nonzero pattern of L(k,:)

CSparse/Double/Factorization/SparseLDL.cs

@@ -311,10 +311,7 @@ void Factorize(CompressedColumnStorage<double> A, IProgress<double> progress)
                 {
                     current += step;
 
-                    if (progress != null)
-                    {
-                        progress.Report(k / (double)n);
-                    }
+                    progress?.Report(k / (double)n);
                 }
 
                 // compute nonzero Pattern of kth row of L, in topological order

CSparse/Double/Factorization/SparseLU.cs

@@ -261,10 +261,7 @@ private void Factorize(CompressedColumnStorage<double> A, double tol, IProgress<
                 {
                     current += step;
 
-                    if (progress != null)
-                    {
-                        progress.Report(k / (double)n);
-                    }
+                    progress?.Report(k / (double)n);
                 }
 
                 // Triangular solve
@@ -380,7 +377,7 @@ private void SymbolicAnalysis(CompressedColumnStorage<double> A, int[] p)
         private int SolveSp(CompressedColumnStorage<double> G, CompressedColumnStorage<double> B,
             int k, int[] xi, double[] x, int[] pinv, bool lo)
         {
-            if (xi == null || x == null) return -1;
+            if (xi is null || x is null) return -1;
 
             var gp = G.ColumnPointers;
             var gi = G.RowIndices;

CSparse/Double/Factorization/SparseQR.cs

@@ -206,7 +206,7 @@ protected override double CreateHouseholder(double[] x, int offset, ref double b
         {
             double s = 0;
             int i;
-            if (x == null) return -1; // check inputs
+            if (x is null) return -1; // check inputs
 
             // s = norm(x)
             for (i = 0; i < n; i++)
@@ -241,7 +241,7 @@ protected override bool ApplyHouseholder(CompressedColumnStorage<double> V, int
             int p = 0;
             double tau = 0;
 
-            if (x == null) return false; // check inputs
+            if (x is null) return false; // check inputs
 
             var vp = V.ColumnPointers;
             var vi = V.RowIndices;

CSparse/Double/SparseMatrix.cs

@@ -274,12 +274,12 @@ public override void TransposeMultiply(double alpha, ReadOnlySpan<double> x, dou
         public override void Add(double alpha, double beta, CompressedColumnStorage<double> other,
             CompressedColumnStorage<double> result)
         {
-            if (other == null)
+            if (other is null)
             {
                 throw new ArgumentNullException(nameof(other));
             }
 
-            if (result == null)
+            if (result is null)
             {
                 throw new ArgumentNullException(nameof(result));
             }
@@ -332,12 +332,12 @@ public override void Add(double alpha, double beta, CompressedColumnStorage<doub
         /// <inheritdoc />
         public override void Multiply(CompressedColumnStorage<double> other, CompressedColumnStorage<double> result)
         {
-            if (other == null)
+            if (other is null)
             {
                 throw new ArgumentNullException(nameof(other));
             }
 
-            if (result == null)
+            if (result is null)
             {
                 throw new ArgumentNullException(nameof(result));
             }
@@ -411,7 +411,7 @@ public override void Multiply(CompressedColumnStorage<double> other, CompressedC
         public override CompressedColumnStorage<double> ParallelMultiply(CompressedColumnStorage<double> other, ParallelOptions options = null)
         {
             // Check inputs
-            if (other == null)
+            if (other is null)
             {
                 throw new ArgumentNullException(nameof(other));
             }
@@ -451,7 +451,7 @@ public override CompressedColumnStorage<double> ParallelMultiply(CompressedColum
                 return Multiply(other);
             }
 
-            if (options == null)
+            if (options is null)
             {
                 options = new ParallelOptions() { MaxDegreeOfParallelism = processorCount };
             }
@@ -563,7 +563,7 @@ public override bool Equals(Matrix<double> other, double tolerance)
         {
             var o = other as SparseMatrix;
 
-            if (o == null)
+            if (o is null)
             {
                 return false;
             }
@@ -659,9 +659,9 @@ internal override int Scatter(int j, double beta, int[] w, double[] x, int mark,
         {
             int i, p;
 
-            if (w == null || mat == null) return -1; // check inputs
+            if (w is null || mat is null) return -1; // check inputs
 
-            if (x == null)
+            if (x is null)
             {
                 throw new ArgumentNullException(nameof(x));
             }

CSparse/Factorization/SparseQR.cs

@@ -130,10 +130,7 @@ protected void Factorize(CompressedColumnStorage<T> A, IProgress<double> progres
                 {
                     current += step;
 
-                    if (progress != null)
-                    {
-                        progress.Report(k / (double)n);
-                    }
+                    progress?.Report(k / (double)n);
                 }
 
                 rp[k] = rnz;      // R(:,k) starts here