/// <summary>Computes the sum of two specific <see cref="DenseMatrix"/> objects, i.e. A + \alpha * B.
/// </summary>
/// <param name="a">The first matrix, i.e. 'A'.</param>
/// <param name="b">The second matrix, i.e. 'B'.</param>
/// <param name="scalar">The scalar \alpha.</param>
/// <returns>The sum A + \alpha * B in its <see cref="DenseMatrix"/> representation.</returns>
private static DenseMatrix Add(DenseMatrix a, DenseMatrix b, double scalar)
{
MatrixSpecialFunction.TestAdditionInput(a, b);
int n = a.RowCount * a.ColumnCount;
var y = new double[n];
int rowCount = a.RowCount;
int columnCount = a.ColumnCount;
if (a.m_TransposeState == BLAS.MatrixTransposeState.NoTranspose)
{
switch (b.m_TransposeState)
{
case BLAS.MatrixTransposeState.NoTranspose:
BLAS.Level1.dcopy(n, a.Data, y);
BLAS.Level1.daxpy(n, scalar, b.Data, y);
break;
case BLAS.MatrixTransposeState.Transpose:
BLAS.Level1.dcopy(n, a.Data, y);
for (int i = 0; i < rowCount; i++)
{
BLAS.Level1.daxpy(columnCount, scalar, b.Data, y, 1, rowCount, i * b.m_RowCount, i);
}
break;
default: throw new InvalidOperationException();
}
return(new DenseMatrix(rowCount, columnCount, y));
}
else // A^t
{
switch (b.m_TransposeState)
{
case BLAS.MatrixTransposeState.NoTranspose:
BLAS.Level1.dcopy(n, a.Data, y);
for (int i = 0; i < rowCount; i++)
{
BLAS.Level1.daxpy(columnCount, scalar, b.Data, y, 1, rowCount, i * b.m_RowCount, i);
}
break;
case BLAS.MatrixTransposeState.Transpose:
BLAS.Level1.dcopy(n, a.Data, y);
BLAS.Level1.daxpy(n, scalar, b.Data, y);
break;
default: throw new InvalidOperationException();
}
return(new DenseMatrix(rowCount, columnCount, y, BLAS.MatrixTransposeState.Transpose));
}
}
/// <summary>Gets 'C = C + \alpha * A, where 'C' represents the matrix specified by the current instance. The current instance will be changed.
/// </summary>
/// <param name="a">The dense matrix 'A' to add.</param>
/// <param name="alpha">The scalar factor \alpha.</param>
/// <returns>The result of the operation, i.e. '\alpha * A + this', which is a reference to the current instance.</returns>
/// <exception cref="ArgumentNullException">Thrown, if <paramref name="a"/> is <c>null</c>.</exception>
/// <exception cref="ArgumentException">Thrown, if the number of rows/columns of <paramref name="a"/> does not coincide with the number of rows/columns of the matrix given by the current instance.</exception>
/// <remarks>The current object will be changed and a reference to the current object will be returned.
/// <para>
/// Use this method for some '+=' or '-=' operator which may performs better than some separate addition.
/// </para></remarks>
public DenseMatrix AddAssignment(DenseMatrix a, double alpha = 1.0)
{
MatrixSpecialFunction.TestAdditionInput(this, a);
if (m_TransposeState == BLAS.MatrixTransposeState.NoTranspose)
{
switch (a.m_TransposeState)
{
case BLAS.MatrixTransposeState.NoTranspose:
BLAS.Level1.daxpy(m_RowCount * m_ColumnCount, alpha, a.m_Data, m_Data);
break;
case BLAS.MatrixTransposeState.Transpose: // c[i+j*m_RowCount] += \alpha * a[j+i*a.m_RowCount] for i=0,..,m_RowCount-1, j=0,..,m_ColumnCount-1
double[] aData = a.Data;
for (int i = 0; i < m_RowCount; i++)
{
BLAS.Level1.daxpy(m_ColumnCount, alpha, aData, m_Data, 1, m_RowCount, i * a.m_RowCount, i);
}
break;
default: throw new InvalidOperationException();
}
}
else if (m_TransposeState == BLAS.MatrixTransposeState.Transpose)
{
switch (a.m_TransposeState)
{
case BLAS.MatrixTransposeState.Transpose:
BLAS.Level1.daxpy(m_RowCount * m_ColumnCount, alpha, a.m_Data, m_Data);
break;
case BLAS.MatrixTransposeState.NoTranspose:
for (int i = 0; i < m_RowCount; i++)
{
BLAS.Level1.daxpy(m_ColumnCount, alpha, a.m_Data, m_Data, a.m_RowCount, 1, i, i * m_RowCount); // m_Data[j + i * m_RowCount] += alpha * a.m_Data[i + j * a.m_RowCount] for j \in [0, m_ColumnCount),
}
break;
default: throw new InvalidOperationException();
}
}
else
{
throw new InvalidOperationException();
}
return(this);
}
/// <summary>Gets C = C + \alpha * A, where C represents the matrix specified by the current instance. The current instance will be changed.
/// </summary>
/// <param name="a">The general band matrix A to add.</param>
/// <param name="alpha">The scalar factor \alpha.</param>
/// <returns>The result of the operation, i.e. \alpha * A + this, which is just a reference of the current instance.</returns>
/// <exception cref="ArgumentNullException">Thrown, if <paramref name="a"/> is <c>null</c>.</exception>
/// <exception cref="ArgumentException">Thrown, if the number of rows/columns of A does not coincide with the number of rows/columns of the matrix given by the current instance.</exception>
/// <remarks>The current object will be changed and a reference to the current object will be returned.
/// <para>
/// Use this method for some '+=' or '-=' operator which may performs better than some separate addition.
/// </para></remarks>
public DenseMatrix AddAssignment(GeneralBandMatrix a, double alpha = 1.0)
{
MatrixSpecialFunction.TestAdditionInput(this, a);
int superPlusSubPlusMainDiagonalCount = a.SuperDiagonalCount + a.SubDiagonalCount + 1;
if (m_TransposeState == BLAS.MatrixTransposeState.NoTranspose)
{
switch (a.DataTransposeState)
{
case BLAS.MatrixTransposeState.NoTranspose:
for (int j = 0; j < m_ColumnCount; j++)
{
int iMin = System.Math.Max(0, j - a.SuperDiagonalCount);
int iMax = System.Math.Min(m_RowCount - 1, j + a.SubDiagonalCount);
for (int i = iMin; i <= iMax; i++)
{
m_Data[i + m_RowCount * j] += alpha * a.Data[j * superPlusSubPlusMainDiagonalCount + (i - j + a.SuperDiagonalCount)];
}
}
break;
case BLAS.MatrixTransposeState.Transpose:
for (int j = 0; j < m_ColumnCount; j++)
{
int iMin = System.Math.Max(0, j - a.SuperDiagonalCount);
int iMax = System.Math.Min(m_RowCount - 1, j + a.SubDiagonalCount);
for (int i = iMin; i <= iMax; i++)
{
m_Data[i + m_RowCount * j] += alpha * a.Data[i * superPlusSubPlusMainDiagonalCount + (j - i + a.SuperDiagonalCount)];
}
}
break;
default: throw new InvalidOperationException();
}
}
else if (m_TransposeState == BLAS.MatrixTransposeState.Transpose)
{
switch (a.DataTransposeState)
{
case BLAS.MatrixTransposeState.NoTranspose:
for (int j = 0; j < ColumnCount; j++) // Property 'ColumnCount' returns the value of m_RowCount
{
int iMin = System.Math.Max(0, j - a.SuperDiagonalCount);
int iMax = System.Math.Min(RowCount - 1, j + a.SubDiagonalCount);
for (int i = iMin; i <= iMax; i++)
{
m_Data[j + m_RowCount * i] += alpha * a.Data[j * superPlusSubPlusMainDiagonalCount + (i - j + a.SuperDiagonalCount)];
}
}
break;
case BLAS.MatrixTransposeState.Transpose:
for (int j = 0; j < ColumnCount; j++) // Property 'ColumnCount' returns the value of m_RowCount
{
int iMin = System.Math.Max(0, j - a.SuperDiagonalCount);
int iMax = System.Math.Min(RowCount - 1, j + a.SubDiagonalCount);
for (int i = iMin; i <= iMax; i++)
{
m_Data[j + m_RowCount * i] += alpha * a.Data[i * superPlusSubPlusMainDiagonalCount + (j - i + a.SuperDiagonalCount)];
}
}
break;
default: throw new InvalidOperationException();
}
}
else
{
throw new InvalidOperationException();
}
return(this);
}
/// <summary>The addition of two <see cref="GeneralBandMatrix"/> objects, i.e. A + \alpha * B.
/// </summary>
/// <param name="a">The first general band matrix A.</param>
/// <param name="b">The second general band matrix B.</param>
/// <param name="scalar">The scalar \alpha.</param>
/// <returns>The result of the operator, i.e. A + \alpha * B.</returns>
/// <exception cref="ArgumentNullException">Thrown, if <paramref name="a"/> or <paramref name="b"/> is <c>null</c>.</exception>
/// <exception cref="ArgumentException">Thrown, if the number of columns of <paramref name="a"/> does not coincide with the number of rows of <paramref name="b"/>.</exception>
private static GeneralBandMatrix Add(GeneralBandMatrix a, GeneralBandMatrix b, double scalar)
{
MatrixSpecialFunction.TestAdditionInput(a, b);
int subDiagonalCount = Math.Max(a.SubDiagonalCount, b.SubDiagonalCount);
int superDiagonalCount = Math.Max(a.SuperDiagonalCount, b.SuperDiagonalCount);
int rowCount = a.RowCount;
int columnCount = a.ColumnCount;
int length = rowCount * (subDiagonalCount + superDiagonalCount + 1);
var c = new double[length];
switch (a.m_TransposeState)
{
case BLAS.MatrixTransposeState.NoTranspose:
if (b.m_TransposeState == BLAS.MatrixTransposeState.NoTranspose)
{
for (int j = 0; j < columnCount; j++)
{
int offSetMatrixA = j * (a.m_SubDiagonalCount + a.m_SuperDiagonalCount + 1);
int offSetMatrixB = j * (b.m_SubDiagonalCount + b.m_SuperDiagonalCount + 1);
int offsetMatrixC = j * (subDiagonalCount + superDiagonalCount + 1);
for (int i = Math.Max(0, j - superDiagonalCount); i <= Math.Min(rowCount - 1, j + subDiagonalCount); i++)
{
double value = 0.0;
if ((i - j <= a.m_SubDiagonalCount) && (j - i <= a.m_SuperDiagonalCount))
{
value += a.m_Data[i - j + a.m_SuperDiagonalCount + offSetMatrixA];
}
if ((i - j <= b.m_SubDiagonalCount) && (j - i <= b.m_SuperDiagonalCount))
{
value += scalar * b.m_Data[i - j + b.m_SuperDiagonalCount + offSetMatrixB];
}
c[i - j + superDiagonalCount + offsetMatrixC] = value;
}
}
}
else
{
int k = b.m_SubDiagonalCount + b.m_SuperDiagonalCount + 1;
for (int j = 0; j < columnCount; j++)
{
int offSetMatrixA = j * (a.m_SubDiagonalCount + a.m_SuperDiagonalCount + 1);
int offsetMatrixC = j * (subDiagonalCount + superDiagonalCount + 1);
for (int i = Math.Max(0, j - superDiagonalCount); i <= Math.Min(rowCount - 1, j + subDiagonalCount); i++)
{
double value = 0.0;
if ((i - j <= a.m_SubDiagonalCount) && (j - i <= a.m_SuperDiagonalCount))
{
value += a.m_Data[i - j + a.m_SuperDiagonalCount + offSetMatrixA];
}
if ((i - j <= b.m_SubDiagonalCount) && (j - i <= b.m_SuperDiagonalCount))
{
value += scalar * b.m_Data[j - i + b.m_SuperDiagonalCount + i * k];
}
c[i - j + superDiagonalCount + offsetMatrixC] = value;
}
}
}
break;
case BLAS.MatrixTransposeState.Transpose:
if (b.m_TransposeState == BLAS.MatrixTransposeState.NoTranspose)
{
int k = a.m_SubDiagonalCount + a.m_SuperDiagonalCount + 1;
for (int j = 0; j < columnCount; j++)
{
int offSetMatrixB = j * (b.m_SubDiagonalCount + b.m_SuperDiagonalCount + 1);
int offsetMatrixC = j * (subDiagonalCount + superDiagonalCount + 1);
for (int i = Math.Max(0, j - superDiagonalCount); i <= Math.Min(rowCount - 1, j + subDiagonalCount); i++)
{
double value = 0.0;
if ((i - j <= a.m_SubDiagonalCount) && (j - i <= a.m_SuperDiagonalCount))
{
value += a.m_Data[j - i + a.m_SuperDiagonalCount + i * k];
}
if ((i - j <= b.m_SubDiagonalCount) && (j - i <= b.m_SuperDiagonalCount))
{
value += scalar * b.m_Data[i - j + b.m_SuperDiagonalCount + offSetMatrixB];
}
c[i - j + superDiagonalCount + offsetMatrixC] = value;
}
}
}
else
{
int ka = a.m_SubDiagonalCount + a.m_SuperDiagonalCount + 1;
int kb = b.m_SubDiagonalCount + b.m_SuperDiagonalCount + 1;
for (int j = 0; j < columnCount; j++)
{
int offsetMatrixC = j * (subDiagonalCount + superDiagonalCount + 1);
for (int i = Math.Max(0, j - superDiagonalCount); i <= Math.Min(rowCount - 1, j + subDiagonalCount); i++)
{
double value = 0.0;
if ((i - j <= a.m_SubDiagonalCount) && (j - i <= a.m_SuperDiagonalCount))
{
value += a.m_Data[j - i + a.m_SuperDiagonalCount + i * ka];
}
if ((i - j <= b.m_SubDiagonalCount) && (j - i <= b.m_SuperDiagonalCount))
{
value += scalar * b.m_Data[j - i + b.m_SuperDiagonalCount + i * kb];
}
c[i - j + superDiagonalCount + offsetMatrixC] = value;
}
}
}
break;
default: throw new InvalidOperationException();
}
return new GeneralBandMatrix(rowCount, columnCount, subDiagonalCount, superDiagonalCount, c);
}