From 41ab904c7f9351aacb8053b34eb29a93880837bb Mon Sep 17 00:00:00 2001
From: Jurgen Van Gael <jurgen.vangael@gmail.com>
Date: Fri, 18 Dec 2009 00:28:04 +0800
Subject: [PATCH] Added Matrix.Clear method.

---
 src/Numerics/LinearAlgebra/Double/DenseMatrix.cs   |  8 ++++++++
 src/Numerics/LinearAlgebra/Double/Matrix.cs        | 14 ++++++++++++++
 .../LinearAlgebraTests/Double/MatrixTests.cs       | 14 ++++++++++++++
 3 files changed, 36 insertions(+)

diff --git a/src/Numerics/LinearAlgebra/Double/DenseMatrix.cs b/src/Numerics/LinearAlgebra/Double/DenseMatrix.cs
index 04aba072..543b16ef 100644
--- a/src/Numerics/LinearAlgebra/Double/DenseMatrix.cs
+++ b/src/Numerics/LinearAlgebra/Double/DenseMatrix.cs
@@ -182,6 +182,14 @@ namespace MathNet.Numerics.LinearAlgebra.Double
             Data[column * RowCount + row] = value;
         }
 
+        /// <summary>
+        /// Sets all values to zero.
+        /// </summary>
+        public override void Clear()
+        {
+            Array.Clear(Data, 0, Data.Length);
+        }
+
         #region Elementary operations
         /// <summary>
         /// Adds another matrix to this matrix. The result will be written into this matrix.
diff --git a/src/Numerics/LinearAlgebra/Double/Matrix.cs b/src/Numerics/LinearAlgebra/Double/Matrix.cs
index e4bcd869..f179f3d0 100644
--- a/src/Numerics/LinearAlgebra/Double/Matrix.cs
+++ b/src/Numerics/LinearAlgebra/Double/Matrix.cs
@@ -412,6 +412,20 @@ namespace MathNet.Numerics.LinearAlgebra.Double
         }
 
         #endregion
+
+        /// <summary>
+        /// Sets all values to zero.
+        /// </summary>
+        public virtual void Clear()
+        {
+            for (int i = 0; i < RowCount; i++)
+            {
+                for (int j = 0; j < ColumnCount; j++)
+                {
+                    At(i, j, 0);
+                }
+            }
+        }
         
         #region Elementary operations
         /// <summary>
diff --git a/src/UnitTests/LinearAlgebraTests/Double/MatrixTests.cs b/src/UnitTests/LinearAlgebraTests/Double/MatrixTests.cs
index 0b81e099..f57667ba 100644
--- a/src/UnitTests/LinearAlgebraTests/Double/MatrixTests.cs
+++ b/src/UnitTests/LinearAlgebraTests/Double/MatrixTests.cs
@@ -162,6 +162,20 @@ namespace MathNet.Numerics.UnitTests.LinearAlgebraTests.Double
         {
         }
 
+        [Test]
+        public void CanClearMatrix()
+        {
+            Matrix matrix = (Matrix) testMatrices["Singular3x3"].Clone();
+            matrix.Clear();
+            for (int i = 0; i < matrix.RowCount; i++)
+            {
+                for (int j = 0; j < matrix.ColumnCount; j++)
+                {
+                    Assert.AreEqual(0, matrix[i, j]);
+                }
+            }
+        }
+
         #region Elementary operations
         [Test]
         [Row("Singular3x3", "Square3x3")]