From 5abb1fa07fa82faf345334112ba63930fffa5cd4 Mon Sep 17 00:00:00 2001
From: RR <richardreader@hotmail.co.uk>
Date: Wed, 20 Jun 2018 22:27:31 +0100
Subject: [PATCH] Addition of SparseMatrix implementation of
 OnTransposeThisAndMultiply method for all numeric types

---
 .../LinearAlgebra/Complex/SparseMatrix.cs     | 29 +++++++++++++++++++
 .../LinearAlgebra/Complex32/SparseMatrix.cs   | 29 +++++++++++++++++++
 .../LinearAlgebra/Double/SparseMatrix.cs      | 29 +++++++++++++++++++
 .../LinearAlgebra/Single/SparseMatrix.cs      | 29 +++++++++++++++++++
 4 files changed, 116 insertions(+)

diff --git a/src/Numerics/LinearAlgebra/Complex/SparseMatrix.cs b/src/Numerics/LinearAlgebra/Complex/SparseMatrix.cs
index 3f2e1b22..03fc2b19 100644
--- a/src/Numerics/LinearAlgebra/Complex/SparseMatrix.cs
+++ b/src/Numerics/LinearAlgebra/Complex/SparseMatrix.cs
@@ -1145,6 +1145,35 @@ namespace MathNet.Numerics.LinearAlgebra.Complex
             }
         }
 
+        /// <summary>
+        /// Multiplies the transpose of this matrix with a vector and places the results into the result vector.
+        /// </summary>
+        /// <param name="rightSide">The vector to multiply with.</param>
+        /// <param name="result">The result of the multiplication.</param>
+        protected override void DoTransposeThisAndMultiply(Vector<Complex> rightSide, Vector<Complex> result)
+        {
+            var rowPointers = _storage.RowPointers;
+            var columnIndices = _storage.ColumnIndices;
+            var values = _storage.Values;
+
+            for (var row = 0; row < RowCount; row++)
+            {
+                var startIndex = rowPointers[row];
+                var endIndex = rowPointers[row + 1];
+
+                if (startIndex == endIndex)
+                {
+                    continue;
+                }
+
+                var rightSideValue = rightSide[row];
+                for (var index = startIndex; index < endIndex; index++)
+                {
+                    result[columnIndices[index]] += values[index] * rightSideValue;
+                }
+            }
+        }
+
         /// <summary>
         /// Pointwise multiplies this matrix with another matrix and stores the result into the result matrix.
         /// </summary>
diff --git a/src/Numerics/LinearAlgebra/Complex32/SparseMatrix.cs b/src/Numerics/LinearAlgebra/Complex32/SparseMatrix.cs
index 11ac2f98..d2394dff 100644
--- a/src/Numerics/LinearAlgebra/Complex32/SparseMatrix.cs
+++ b/src/Numerics/LinearAlgebra/Complex32/SparseMatrix.cs
@@ -1144,6 +1144,35 @@ namespace MathNet.Numerics.LinearAlgebra.Complex32
             }
         }
 
+        /// <summary>
+        /// Multiplies the transpose of this matrix with a vector and places the results into the result vector.
+        /// </summary>
+        /// <param name="rightSide">The vector to multiply with.</param>
+        /// <param name="result">The result of the multiplication.</param>
+        protected override void DoTransposeThisAndMultiply(Vector<Complex32> rightSide, Vector<Complex32> result)
+        {
+            var rowPointers = _storage.RowPointers;
+            var columnIndices = _storage.ColumnIndices;
+            var values = _storage.Values;
+
+            for (var row = 0; row < RowCount; row++)
+            {
+                var startIndex = rowPointers[row];
+                var endIndex = rowPointers[row + 1];
+
+                if (startIndex == endIndex)
+                {
+                    continue;
+                }
+
+                var rightSideValue = rightSide[row];
+                for (var index = startIndex; index < endIndex; index++)
+                {
+                    result[columnIndices[index]] += values[index] * rightSideValue;
+                }
+            }
+        }
+
         /// <summary>
         /// Pointwise multiplies this matrix with another matrix and stores the result into the result matrix.
         /// </summary>
diff --git a/src/Numerics/LinearAlgebra/Double/SparseMatrix.cs b/src/Numerics/LinearAlgebra/Double/SparseMatrix.cs
index 51d35c57..dfaf0301 100644
--- a/src/Numerics/LinearAlgebra/Double/SparseMatrix.cs
+++ b/src/Numerics/LinearAlgebra/Double/SparseMatrix.cs
@@ -1142,6 +1142,35 @@ namespace MathNet.Numerics.LinearAlgebra.Double
             }
         }
 
+        /// <summary>
+        /// Multiplies the transpose of this matrix with a vector and places the results into the result vector.
+        /// </summary>
+        /// <param name="rightSide">The vector to multiply with.</param>
+        /// <param name="result">The result of the multiplication.</param>
+        protected override void DoTransposeThisAndMultiply(Vector<double> rightSide, Vector<double> result)
+        {
+            var rowPointers = _storage.RowPointers;
+            var columnIndices = _storage.ColumnIndices;
+            var values = _storage.Values;
+
+            for (var row = 0; row < RowCount; row++)
+            {
+                var startIndex = rowPointers[row];
+                var endIndex = rowPointers[row + 1];
+
+                if (startIndex == endIndex)
+                {
+                    continue;
+                }
+
+                var rightSideValue = rightSide[row];
+                for (var index = startIndex; index < endIndex; index++)
+                {
+                    result[columnIndices[index]] += values[index] * rightSideValue;
+                }
+            }
+        }
+
         /// <summary>
         /// Pointwise multiplies this matrix with another matrix and stores the result into the result matrix.
         /// </summary>
diff --git a/src/Numerics/LinearAlgebra/Single/SparseMatrix.cs b/src/Numerics/LinearAlgebra/Single/SparseMatrix.cs
index 5391b975..8bd8e083 100644
--- a/src/Numerics/LinearAlgebra/Single/SparseMatrix.cs
+++ b/src/Numerics/LinearAlgebra/Single/SparseMatrix.cs
@@ -1147,6 +1147,35 @@ namespace MathNet.Numerics.LinearAlgebra.Single
             }
         }
 
+        /// <summary>
+        /// Multiplies the transpose of this matrix with a vector and places the results into the result vector.
+        /// </summary>
+        /// <param name="rightSide">The vector to multiply with.</param>
+        /// <param name="result">The result of the multiplication.</param>
+        protected override void DoTransposeThisAndMultiply(Vector<float> rightSide, Vector<float> result)
+        {
+            var rowPointers = _storage.RowPointers;
+            var columnIndices = _storage.ColumnIndices;
+            var values = _storage.Values;
+
+            for (var row = 0; row < RowCount; row++)
+            {
+                var startIndex = rowPointers[row];
+                var endIndex = rowPointers[row + 1];
+
+                if (startIndex == endIndex)
+                {
+                    continue;
+                }
+
+                var rightSideValue = rightSide[row];
+                for (var index = startIndex; index < endIndex; index++)
+                {
+                    result[columnIndices[index]] += values[index] * rightSideValue;
+                }
+            }
+        }
+
         /// <summary>
         /// Pointwise multiplies this matrix with another matrix and stores the result into the result matrix.
         /// </summary>