/// <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 SymmetricBandMatrix operator *(double s, SymmetricBandMatrix A)
{
SymmetricBandMatrix C = new SymmetricBandMatrix(A.RowCount, A.LowerBandWidth);
double[] AData = A.Data;
double[] CData = C.Data;
Matrix.MultiplicationSM(s, AData, CData);
return(C);
}
/// <summary>
///Computes all the eigenvalues of
/// a real symmetric band matrix A.
/// </summary>
/// <param name="A">The real symmetric band matrix A.</param>
/// <returns>The eigenvalues.</returns>
public Matrix GetEigenvalues(SymmetricBandMatrix A)
{
if (this._dsbev == null)
{
this._dsbev = new DSBEV();
}
this.CheckDimensions(A);
Matrix SymmetricBand = A.GetSymmetricBandPackedMatrix();
double[] SymmetricBandData = SymmetricBand.Data;
Matrix EigenVects = new Matrix(1, 1); //Se pone (1,1) pues nos e usaran
double[] EigenVectsData = EigenVects.Data;
Matrix EigenVals = new Matrix(A.RowCount, 1);
double[] EigenValsData = EigenVals.Data;
int Info = 0;
double[] Work = new double[3 * A.RowCount - 2];
_dsbev.Run("N", "U", A.RowCount, A.UpperBandWidth, ref SymmetricBandData, 0, SymmetricBand.RowCount, ref EigenValsData, 0, ref EigenVectsData, 0, A.RowCount, ref Work, 0, 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, the algorithm failed to converge; i
/// off-diagonal elements of an intermediate tridiagonal
/// form did not converge to zero.
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("The algorithm failed to converge.");
}
#endregion
return(EigenVals);
}
/// <summary>Generate a BandMatrix with random elements</summary>
/// <param name="size">Size</param>
/// <param name="BandWidth">Number of bands below or above the main diagonal</param>
public static SymmetricBandMatrix Random(int size, int BandWidth)
{
System.Random random = new System.Random();
SymmetricBandMatrix X = new SymmetricBandMatrix(size, BandWidth);
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>
/// <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 SymmetricBandMatrix operator -(SymmetricBandMatrix A, SymmetricBandMatrix B)
{
if (B.RowCount != A.RowCount || B.ColumnCount != A.ColumnCount || B.LowerBandWidth != A.LowerBandWidth || B.UpperBandWidth != A.UpperBandWidth)
{
throw new System.ArgumentException("Matrix dimensions are not valid.");
}
SymmetricBandMatrix C = new SymmetricBandMatrix(A.RowCount, A.LowerBandWidth);
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>
/// Creates a copy of the matrix.
/// </summary>
/// <returns>The copy of the Matrix.</returns>
public SymmetricBandMatrix Clone()
{
SymmetricBandMatrix NewBandMatix = new SymmetricBandMatrix(this._RowCount, this.MeLowerBandWidth, this._Data);
return NewBandMatix;
}
/// <summary>Generate a BandMatrix with random elements</summary>
/// <param name="size">Size</param>
/// <param name="BandWidth">Number of bands below or above the main diagonal</param>
public static SymmetricBandMatrix Random(int size, int BandWidth)
{
System.Random random = new System.Random();
SymmetricBandMatrix X = new SymmetricBandMatrix(size, BandWidth);
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>
/// <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 SymmetricBandMatrix operator -(SymmetricBandMatrix A, SymmetricBandMatrix B)
{
if (B.RowCount != A.RowCount || B.ColumnCount != A.ColumnCount || B.LowerBandWidth != A.LowerBandWidth || B.UpperBandWidth != A.UpperBandWidth)
{
throw new System.ArgumentException("Matrix dimensions are not valid.");
}
SymmetricBandMatrix C = new SymmetricBandMatrix(A.RowCount, A.LowerBandWidth);
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 SymmetricBandMatrix operator *(double s, SymmetricBandMatrix A)
{
SymmetricBandMatrix C = new SymmetricBandMatrix(A.RowCount, A.LowerBandWidth);
double[] AData = A.Data;
double[] CData = C.Data;
Matrix.MultiplicationSM(s, AData, CData);
return C;
}
/// <summary>
///Computes all the eigenvalues and eigenvectors of
/// a real symmetric band matrix A.
/// </summary>
/// <param name="A">The real symmetric band matrix A.</param>
/// <param name="EigenVects">The eigenvectors.</param>
/// <returns>The eigenvalues.</returns>
public Matrix GetEigenvalues(SymmetricBandMatrix A, out Matrix EigenVects)
{
if (this._dsbev == null) this._dsbev = new DSBEV();
this.CheckDimensions(A);
Matrix SymmetricBand = A.GetSymmetricBandPackedMatrix();
double[] SymmetricBandData = SymmetricBand.Data;
EigenVects = new Matrix(A.RowCount, A.ColumnCount);
double[] EigenVectsData = EigenVects.Data;
Matrix EigenVals = new Matrix(A.RowCount, 1);
double[] EigenValsData = EigenVals.Data;
int Info = 0;
double[] Work = new double[3 * A.RowCount - 2];
_dsbev.Run("V", "U", A.RowCount, A.UpperBandWidth, ref SymmetricBandData, 0, SymmetricBand.RowCount, ref EigenValsData, 0, ref EigenVectsData, 0, A.RowCount, ref Work, 0, 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, the algorithm failed to converge; i
/// off-diagonal elements of an intermediate tridiagonal
/// form did not converge to zero.
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("The algorithm failed to converge.");
}
#endregion
return EigenVals;
}
/// <summary>
/// Creates a copy of the matrix.
/// </summary>
/// <returns>The copy of the Matrix.</returns>
public SymmetricBandMatrix Clone()
{
SymmetricBandMatrix NewBandMatix = new SymmetricBandMatrix(this._RowCount, this.MeLowerBandWidth, this._Data);
return(NewBandMatix);
}
