/// <summary>
/// Run example
/// </summary>
/// <seealso cref="http://en.wikipedia.org/wiki/Matrix_multiplication#Scalar_multiplication">Multiply matrix by scalar</seealso>
/// <seealso cref="http://reference.wolfram.com/mathematica/tutorial/MultiplyingVectorsAndMatrices.html">Multiply matrix by vector</seealso>
/// <seealso cref="http://en.wikipedia.org/wiki/Matrix_multiplication#Matrix_product">Multiply matrix by matrix</seealso>
/// <seealso cref="http://en.wikipedia.org/wiki/Matrix_multiplication#Hadamard_product">Pointwise multiplies matrix with another matrix</seealso>
/// <seealso cref="http://en.wikipedia.org/wiki/Matrix_%28mathematics%29#Basic_operations">Addition and subtraction</seealso>
public void Run()
{
// Initialize IFormatProvider to print matrix/vector data
var formatProvider = (CultureInfo)CultureInfo.InvariantCulture.Clone();
formatProvider.TextInfo.ListSeparator = " ";
// Create matrix "A"
var matrixA = new DenseMatrix(new[,] { { 1.0, 2.0, 3.0 }, { 4.0, 5.0, 6.0 }, { 7.0, 8.0, 9.0 } });
Console.WriteLine(@"Matrix A");
Console.WriteLine(matrixA.ToString("#0.00\t", formatProvider));
Console.WriteLine();
// Create matrix "B"
var matrixB = new DenseMatrix(new[,] { { 1.0, 3.0, 5.0 }, { 2.0, 4.0, 6.0 }, { 3.0, 5.0, 7.0 } });
Console.WriteLine(@"Matrix B");
Console.WriteLine(matrixB.ToString("#0.00\t", formatProvider));
Console.WriteLine();
// Multiply matrix by scalar
// 1. Using operator "*"
var resultM = 3.0 * matrixA;
Console.WriteLine(@"Multiply matrix by scalar using operator *. (result = 3.0 * A)");
Console.WriteLine(resultM.ToString("#0.00\t", formatProvider));
Console.WriteLine();
// 2. Using Multiply method and getting result into different matrix instance
resultM = (DenseMatrix)matrixA.Multiply(3.0);
Console.WriteLine(@"Multiply matrix by scalar using method Multiply. (result = A.Multiply(3.0))");
Console.WriteLine(resultM.ToString("#0.00\t", formatProvider));
Console.WriteLine();
// 3. Using Multiply method and updating matrix itself
matrixA.Multiply(3.0, matrixA);
Console.WriteLine(@"Multiply matrix by scalar using method Multiply. (A.Multiply(3.0, A))");
Console.WriteLine(matrixA.ToString("#0.00\t", formatProvider));
Console.WriteLine();
// Multiply matrix by vector (right-multiply)
var vector = new DenseVector(new[] { 1.0, 2.0, 3.0 });
Console.WriteLine(@"Vector");
Console.WriteLine(vector.ToString("#0.00\t", formatProvider));
Console.WriteLine();
// 1. Using operator "*"
var resultV = matrixA * vector;
Console.WriteLine(@"Multiply matrix by vector using operator *. (result = A * vec)");
Console.WriteLine(resultV.ToString("#0.00\t", formatProvider));
Console.WriteLine();
// 2. Using Multiply method and getting result into different vector instance
resultV = (DenseVector)matrixA.Multiply(vector);
Console.WriteLine(@"Multiply matrix by vector using method Multiply. (result = A.Multiply(vec))");
Console.WriteLine(resultV.ToString("#0.00\t", formatProvider));
Console.WriteLine();
// 3. Using Multiply method and updating vector itself
matrixA.Multiply(vector, vector);
Console.WriteLine(@"Multiply matrix by vector using method Multiply. (A.Multiply(vec, vec))");
Console.WriteLine(vector.ToString("#0.00\t", formatProvider));
Console.WriteLine();
// Multiply vector by matrix (left-multiply)
// 1. Using operator "*"
resultV = vector * matrixA;
Console.WriteLine(@"Multiply vector by matrix using operator *. (result = vec * A)");
Console.WriteLine(resultV.ToString("#0.00\t", formatProvider));
Console.WriteLine();
// 2. Using LeftMultiply method and getting result into different vector instance
resultV = (DenseVector)matrixA.LeftMultiply(vector);
Console.WriteLine(@"Multiply vector by matrix using method LeftMultiply. (result = A.LeftMultiply(vec))");
Console.WriteLine(resultV.ToString("#0.00\t", formatProvider));
Console.WriteLine();
// 3. Using LeftMultiply method and updating vector itself
matrixA.LeftMultiply(vector, vector);
Console.WriteLine(@"Multiply vector by matrix using method LeftMultiply. (A.LeftMultiply(vec, vec))");
Console.WriteLine(vector.ToString("#0.00\t", formatProvider));
Console.WriteLine();
// Multiply matrix by matrix
// 1. Using operator "*"
resultM = matrixA * matrixB;
Console.WriteLine(@"Multiply matrix by matrix using operator *. (result = A * B)");
Console.WriteLine(resultM.ToString("#0.00\t", formatProvider));
Console.WriteLine();
// 2. Using Multiply method and getting result into different matrix instance
resultM = (DenseMatrix)matrixA.Multiply(matrixB);
Console.WriteLine(@"Multiply matrix by matrix using method Multiply. (result = A.Multiply(B))");
Console.WriteLine(resultM.ToString("#0.00\t", formatProvider));
Console.WriteLine();
// 3. Using Multiply method and updating matrix itself
matrixA.Multiply(matrixB, matrixA);
Console.WriteLine(@"Multiply matrix by matrix using method Multiply. (A.Multiply(B, A))");
Console.WriteLine(matrixA.ToString("#0.00\t", formatProvider));
Console.WriteLine();
// Pointwise multiplies matrix with another matrix
// 1. Using PointwiseMultiply method and getting result into different matrix instance
resultM = (DenseMatrix)matrixA.PointwiseMultiply(matrixB);
Console.WriteLine(@"Pointwise multiplies matrix with another matrix using method PointwiseMultiply. (result = A.PointwiseMultiply(B))");
Console.WriteLine(resultM.ToString("#0.00\t", formatProvider));
Console.WriteLine();
// 2. Using PointwiseMultiply method and updating matrix itself
matrixA.PointwiseMultiply(matrixB, matrixA);
Console.WriteLine(@"Pointwise multiplies matrix with another matrix using method PointwiseMultiply. (A.PointwiseMultiply(B, A))");
Console.WriteLine(matrixA.ToString("#0.00\t", formatProvider));
Console.WriteLine();
// Pointwise divide matrix with another matrix
// 1. Using PointwiseDivide method and getting result into different matrix instance
resultM = (DenseMatrix)matrixA.PointwiseDivide(matrixB);
Console.WriteLine(@"Pointwise divide matrix with another matrix using method PointwiseDivide. (result = A.PointwiseDivide(B))");
Console.WriteLine(resultM.ToString("#0.00\t", formatProvider));
Console.WriteLine();
// 2. Using PointwiseDivide method and updating matrix itself
matrixA.PointwiseDivide(matrixB, matrixA);
Console.WriteLine(@"Pointwise divide matrix with another matrix using method PointwiseDivide. (A.PointwiseDivide(B, A))");
Console.WriteLine(matrixA.ToString("#0.00\t", formatProvider));
Console.WriteLine();
// Addition
// 1. Using operator "+"
resultM = matrixA + matrixB;
Console.WriteLine(@"Add matrices using operator +. (result = A + B)");
Console.WriteLine(resultM.ToString("#0.00\t", formatProvider));
Console.WriteLine();
// 2. Using Add method and getting result into different matrix instance
resultM = (DenseMatrix)matrixA.Add(matrixB);
Console.WriteLine(@"Add matrices using method Add. (result = A.Add(B))");
Console.WriteLine(resultM.ToString("#0.00\t", formatProvider));
Console.WriteLine();
// 3. Using Add method and updating matrix itself
matrixA.Add(matrixB, matrixA);
Console.WriteLine(@"Add matrices using method Add. (A.Add(B, A))");
Console.WriteLine(matrixA.ToString("#0.00\t", formatProvider));
Console.WriteLine();
// Subtraction
// 1. Using operator "-"
resultM = matrixA - matrixB;
Console.WriteLine(@"Subtract matrices using operator -. (result = A - B)");
Console.WriteLine(resultM.ToString("#0.00\t", formatProvider));
Console.WriteLine();
// 2. Using Subtract method and getting result into different matrix instance
resultM = (DenseMatrix)matrixA.Subtract(matrixB);
Console.WriteLine(@"Subtract matrices using method Subtract. (result = A.Subtract(B))");
Console.WriteLine(resultM.ToString("#0.00\t", formatProvider));
Console.WriteLine();
// 3. Using Subtract method and updating matrix itself
matrixA.Subtract(matrixB, matrixA);
Console.WriteLine(@"Subtract matrices using method Subtract. (A.Subtract(B, A))");
Console.WriteLine(matrixA.ToString("#0.00\t", formatProvider));
Console.WriteLine();
// Divide by scalar
// 1. Using Divide method and getting result into different matrix instance
resultM = (DenseMatrix)matrixA.Divide(3.0);
Console.WriteLine(@"Divide matrix by scalar using method Divide. (result = A.Divide(3.0))");
Console.WriteLine(resultM.ToString("#0.00\t", formatProvider));
Console.WriteLine();
// 2. Using Divide method and updating matrix itself
matrixA.Divide(3.0, matrixA);
Console.WriteLine(@"Divide matrix by scalar using method Divide. (A.Divide(3.0, A))");
Console.WriteLine(matrixA.ToString("#0.00\t", formatProvider));
Console.WriteLine();
}
public void CanSubtractSparseMatricesBothWays()
{
var m1 = new SparseMatrix(1, 3);
var m2 = SparseMatrix.OfArray(new double[,] { { 0, 1, 1 } });
var diff1 = m1 - m2;
var diff2 = m2 - m1;
Assert.IsTrue(diff1.Equals(m2.Negate()));
Assert.IsTrue(diff1.Equals(diff2.Negate()));
var sparseResult = new SparseMatrix(1, 3);
sparseResult.Subtract(m2, sparseResult);
Assert.IsTrue(sparseResult.Equals(diff1));
sparseResult = SparseMatrix.OfArray(new double[,] { { 0, 1, 1 } });
sparseResult.Subtract(m1, sparseResult);
Assert.IsTrue(sparseResult.Equals(diff2));
sparseResult = SparseMatrix.OfArray(new double[,] { { 0, 1, 1 } });
m1.Subtract(sparseResult, sparseResult);
Assert.IsTrue(sparseResult.Equals(diff1));
sparseResult = SparseMatrix.OfArray(new double[,] { { 0, 1, 1 } });
sparseResult.Subtract(sparseResult, sparseResult);
Assert.IsTrue(sparseResult.Equals(0*diff1));
var denseResult = new DenseMatrix(1, 3);
denseResult.Subtract(m2, denseResult);
Assert.IsTrue(denseResult.Equals(diff1));
denseResult = DenseMatrix.OfArray(new double[,] {{0, 1, 1}});
denseResult.Subtract(m1, denseResult);
Assert.IsTrue(denseResult.Equals(diff2));
var m3 = DenseMatrix.OfArray(new double[,] {{0, 1, 1}});
var diff3 = m1 - m3;
var diff4 = m3 - m1;
Assert.IsTrue(diff3.Equals(m3.Negate()));
Assert.IsTrue(diff3.Equals(diff4.Negate()));
}
