/// <summary>
/// Scalar-Matrix multiplication.
/// </summary>
/// <param name="s"> The left side scalar of the multiplication operator.</param>
/// <param name="A">The right side matrix of the multiplication operator.</param>
/// <returns>A matrix that represents the result of the multiplication.</returns>
public static TridiagonalMatrix operator *(double s, TridiagonalMatrix A)
{
TridiagonalMatrix C = new TridiagonalMatrix(A.RowCount);
double[] AData = A.Data;
double[] CData = C.Data;
Matrix.MultiplicationSM(s, AData, CData);
return(C);
}
/// <summary>Generate a TridiagonalMatrix with random elements</summary>
/// <param name="size">Size</param>
public static TridiagonalMatrix Random(int size)
{
System.Random random = new System.Random();
TridiagonalMatrix X = new TridiagonalMatrix(size);
double[] XData = X.Data;
for (int j = 0; j < X.ColumnCount; j++)
{
for (int i = 0; i < X.RowCount; i++)
{
X[i, j] = random.NextDouble();
}
}
return(X);
}
/// <summary>
/// Computes the solution to a real system of linear equations
/// A * X = B, where A is a tridiagonal matrix.
/// </summary>
/// <param name="A">The tridiagonal matrix.</param>
/// <param name="B">The matrix containing the right-hand side of the linear system.</param>
/// <returns>A matrix containing the solution to the linear system of equations.</returns>
public Matrix Solve(TridiagonalMatrix A, Matrix B)
{
if (this._dgtsv == null)
{
this._dgtsv = new DGTSV();
}
this.CheckDimensions(A, B);
Matrix Solution = B.Clone();
double[] SolutionData = Solution.Data;
double[] Diagonal;
double[] SubDiagonal;
double[] SuperDiagonal;
A.GetPackedMatrix(out SubDiagonal, out SuperDiagonal, out Diagonal);
int[] IPIV = new int[A.RowCount];
int Info = 0;
this._dgtsv.Run(A.RowCount, B.ColumnCount, ref SubDiagonal, 0, ref Diagonal, 0, ref SuperDiagonal, 0, ref SolutionData, 0, Solution.RowCount, ref Info);
#region Error
/// = 0: successful exit
/// .LT. 0: if INFO = -i, the i-th argument had an illegal value
/// .GT. 0: if INFO = i, U(i,i) is exactly zero, and the solution
/// has not been computed. The factorization has not been
/// completed unless i = N.
if (Info < 0)
{
string infoSTg = Math.Abs(Info).ToString();
throw new ArgumentException("the " + infoSTg + " -th argument had an illegal value");
}
else if (Info > 0)
{
string infoSTg = Math.Abs(Info).ToString();
throw new Exception("U(" + infoSTg + "," + infoSTg + ") is exactly zero. and the solution has not been computed. The factorization has not been completed unless i = N.");
}
#endregion
return(Solution);
}
/// <summary>
/// Matrix subtraction.
/// </summary>
/// <param name="A"> The left side matrix of the subtraction operator.</param>
/// <param name="B">The right side matrix of the subtraction operator.</param>
/// <returns>A matrix that represents the result of the matrix subtraction.</returns>
public static TridiagonalMatrix operator -(TridiagonalMatrix A, TridiagonalMatrix B)
{
if (B.RowCount != A.RowCount || B.ColumnCount != A.ColumnCount)
{
throw new System.ArgumentException("Matrix dimensions are not valid.");
}
TridiagonalMatrix C = new TridiagonalMatrix(A.RowCount);
double[] AData = A.Data;
double[] BData = B.Data;
double[] CData = C.Data;
for (int i = 0; i < AData.Length; i++)
{
CData[i] = AData[i] - BData[i];
}
return(C);
}
/// <summary>
/// Scalar-Matrix multiplication.
/// </summary>
/// <param name="s"> The left side scalar of the multiplication operator.</param>
/// <param name="A">The right side matrix of the multiplication operator.</param>
/// <returns>A matrix that represents the result of the multiplication.</returns>
public static TridiagonalMatrix operator *(double s, TridiagonalMatrix A)
{
TridiagonalMatrix C = new TridiagonalMatrix(A.RowCount);
double[] AData = A.Data;
double[] CData = C.Data;
Matrix.MultiplicationSM(s, AData, CData);
return C;
}
public TridiagonalMatrix Clone()
{
TridiagonalMatrix NewMatrix = new TridiagonalMatrix(this._RowCount, this._Data);
return NewMatrix;
}
/// <summary>Generate a TridiagonalMatrix with random elements</summary>
/// <param name="size">Size</param>
public static TridiagonalMatrix Random(int size)
{
System.Random random = new System.Random();
TridiagonalMatrix X = new TridiagonalMatrix(size);
double[] XData = X.Data;
for (int j = 0; j < X.ColumnCount; j++)
{
for (int i = 0; i < X.RowCount; i++)
{
X[i, j] = random.NextDouble();
}
}
return X;
}
/// <summary>
/// Matrix subtraction.
/// </summary>
/// <param name="A"> The left side matrix of the subtraction operator.</param>
/// <param name="B">The right side matrix of the subtraction operator.</param>
/// <returns>A matrix that represents the result of the matrix subtraction.</returns>
public static TridiagonalMatrix operator -(TridiagonalMatrix A, TridiagonalMatrix B)
{
if (B.RowCount != A.RowCount || B.ColumnCount != A.ColumnCount)
{
throw new System.ArgumentException("Matrix dimensions are not valid.");
}
TridiagonalMatrix C = new TridiagonalMatrix(A.RowCount);
double[] AData = A.Data;
double[] BData = B.Data;
double[] CData = C.Data;
for (int i = 0; i < AData.Length; i++)
{
CData[i] = AData[i] - BData[i];
}
return C;
}
/// <summary>
/// Computes the solution to a real system of linear equations
/// A * X = B, where A is a tridiagonal matrix.
/// </summary>
/// <param name="A">The tridiagonal matrix.</param>
/// <param name="B">The matrix containing the right-hand side of the linear system.</param>
/// <returns>A matrix containing the solution to the linear system of equations.</returns>
public Matrix Solve(TridiagonalMatrix A, Matrix B)
{
if (this._dgtsv == null) this._dgtsv = new DGTSV();
this.CheckDimensions(A, B);
Matrix Solution = B.Clone();
double[] SolutionData = Solution.Data;
double[] Diagonal;
double[] SubDiagonal;
double[] SuperDiagonal;
A.GetPackedMatrix(out SubDiagonal, out SuperDiagonal, out Diagonal);
int[] IPIV = new int[A.RowCount];
int Info = 0;
this._dgtsv.Run(A.RowCount, B.ColumnCount, ref SubDiagonal, 0, ref Diagonal, 0, ref SuperDiagonal, 0, ref SolutionData, 0, Solution.RowCount, ref Info);
#region Error
/// = 0: successful exit
/// .LT. 0: if INFO = -i, the i-th argument had an illegal value
/// .GT. 0: if INFO = i, U(i,i) is exactly zero, and the solution
/// has not been computed. The factorization has not been
/// completed unless i = N.
if (Info < 0)
{
string infoSTg = Math.Abs(Info).ToString();
throw new ArgumentException("the " + infoSTg + " -th argument had an illegal value");
}
else if (Info > 0)
{
string infoSTg = Math.Abs(Info).ToString();
throw new Exception("U(" + infoSTg + "," + infoSTg + ") is exactly zero. and the solution has not been computed. The factorization has not been completed unless i = N.");
}
#endregion
return Solution;
}
public TridiagonalMatrix Clone()
{
TridiagonalMatrix NewMatrix = new TridiagonalMatrix(this._RowCount, this._Data);
return(NewMatrix);
}