Managed Lapack.QROrthogonal Multiply Method
Overwrites the general real M-by-N matrix C with SIDE = 'L' SIDE = 'R' TRANS = 'N': Q * C C * Q TRANS = 'T': QT * C C * QT where Q is a real orthogonal matrix defined as the product of k elementary reflectors Q = H(1) H(2) .
Definition
Namespace: Extreme.Mathematics.LinearAlgebra.Implementation
Assembly: Extreme.Numerics (in Extreme.Numerics.dll) Version: 8.1.23
C#
Assembly: Extreme.Numerics (in Extreme.Numerics.dll) Version: 8.1.23
public override void QROrthogonalMultiply(
MatrixOperationSide side,
TransposeOperation trans,
int m,
int n,
int k,
Array2D<double> a,
Array1D<double> tau,
Array2D<double> c,
out int info
)
Parameters
- side MatrixOperationSide
= 'L': apply Q or QT from the Left; = 'R': apply Q or QT from the Right.
- trans TransposeOperation
= 'N': No transpose, apply Q; = 'T': Transpose, apply QT.
- m Int32
The number of rows of the matrix C. M >= 0.
- n Int32
The number of columns of the matrix C. N >= 0.
- k Int32
The number of elementary reflectors whose product defines the matrix Q. If SIDE = 'L', M >= K >= 0; if SIDE = 'R', N >= K >= 0.
- a Array2D<Double>
Dimension (LDA,K) The i-th column must contain the vector which defines the elementary reflector H(i), for i = 1,2,...,k, as returned by DGEQRF in the first k columns of its array argument A. A is modified by the routine but restored on exit.
The leading dimension of the array A. If SIDE = 'L', LDA >= max(1,M); if SIDE = 'R', LDA >= max(1,N).
- tau Array1D<Double>
Dimension (K) TAU(i) must contain the scalar factor of the elementary reflector H(i), as returned by DGEQRF.
- c Array2D<Double>
Dimension (LDC,N) On entry, the M-by-N matrix C. On exit, C is overwritten by Q*C or QT*C or C*QT or C*Q.
The leading dimension of the array C. LDC >= max(1,M).
- info Int32
= 0: successful exit < 0: if INFO = -i, the i-th argument had an illegal value
Remarks
. . H(k) as returned by DGEQRF. Q is of order M if SIDE = 'L' and of order N if SIDE = 'R'.
This method corresponds to the LAPACK routine DORMQR.