Fix: Fix incorrect dimensions for seed matrix

* Seed matrix now receives the n dimension of the input matrix as its n
  dimension

src/SparseTransform/Convert/MatrixMarketWriter.cs

@@ -38,12 +38,10 @@ namespace SparseTransform.Convert
         /// <returns>MatrixMarket string</returns>
         public String Write(IGraph graph)
         {
-            IntegerMatrix? seedMatrix = graph.ToSeedMatrix(_inputMatrix.RowCount);
+            IntegerMatrix? seedMatrix = graph.ToSeedMatrix(_inputMatrix.ColumnCount);
             if (_seed)
             {
-                // ziemlich wilder ausdruck, wa? Liefert die seed matrix aus einem AdjacencyGraph oder BipartiteGraph. (je nachdem was IGraph ist)
-                
-                if (seedMatrix is IntegerMatrix && seedMatrix.RowCount != 0)
+                if (seedMatrix is IntegerMatrix && seedMatrix.ColumnCount != 0)
                 {
                     return seedMatrix.ToMatrixMarketString();
                 }
@@ -51,7 +49,7 @@ namespace SparseTransform.Convert
             }
             else
             {
-                if (seedMatrix is IntegerMatrix && _inputMatrix is DoubleMatrix && seedMatrix.RowCount != 0)
+                if (seedMatrix is IntegerMatrix && _inputMatrix is DoubleMatrix && seedMatrix.ColumnCount != 0)
                 {
                     return CalculateCompressedMatrix(_inputMatrix, seedMatrix).ToMatrixMarketString();
                 }