ManagedLapack.RQDecompose Method

Definition

Namespace: Numerics.NET.LinearAlgebra.Implementation
Assembly: Numerics.NET (in Numerics.NET.dll) Version: 9.0.3

Overload List

RQDecompose(Int32, Int32, Array2D<TComplex>, Array1D<TComplex>, Int32) 
RQDecompose(Int32, Int32, Span2D<TComplex>, Span<TComplex>, Int32) 
RQDecompose(Int32, Int32, Array2D<TComplex>, Array1D<TComplex>, Int32)

Computes an RQ factorization of a complex M-by-N matrix A: A = R * Q.

RQDecompose(Int32, Int32, Span2D<TComplex>, Span<TComplex>, Int32)

Computes an RQ factorization of a complex M-by-N matrix A: A = R * Q.

RQDecompose(Int32, Int32, Span<Complex<Double>>, Int32, Span<Complex<Double>>, Int32)

Computes an RQ factorization of a complex M-by-N matrix A: A = R * Q.

RQDecompose(Int32, Int32, Span<Double>, Int32, Span<Double>, Int32)

Computes an RQ factorization of a complex M-by-N matrix A: A = R * Q.

RQDecompose(Int32, Int32, Span<Complex<Double>>, Int32, Span<Complex<Double>>, Int32)

Computes an RQ factorization of a complex M-by-N matrix A: A = R * Q.

C#
public override void RQDecompose(
	int m,
	int n,
	Span<Complex<double>> a,
	int lda,
	Span<Complex<double>> tau,
	out int info
)

Parameters

m  Int32
C#
M is INTEGER
The number of rows of the matrix A.  M >= 0.
n  Int32
C#
N is INTEGER
The number of columns of the matrix A.  N >= 0.
a  Span<Complex<Double>>
C#
A is COMPLEX*16 array, dimension (LDA,N)
On entry, the M-by-N matrix A.
On exit,
if m <= n, the upper triangle of the subarray
A(1:m,n-m+1:n) contains the M-by-M upper triangular matrix R;
if m >= n, the elements on and above the (m-n)-th subdiagonal
contain the M-by-N upper trapezoidal matrix R;
the remaining elements, with the array TAU, represent the
unitary matrix Q as a product of min(m,n) elementary
reflectors (see Further Details).
lda  Int32
C#
LDA is INTEGER
The leading dimension of the array A.  LDA >= max(1,M).
tau  Span<Complex<Double>>
C#
TAU is COMPLEX*16 array, dimension (min(M,N))
The scalar factors of the elementary reflectors (see Further
Details).
info  Int32
C#
INFO is INTEGER
= 0:  successful exit
< 0:  if INFO = -i, the i-th argument had an illegal value

Remarks

Further Details:

C#
The matrix Q is represented as a product of elementary reflectors
   Q = H(1)**H H(2)**H . . . H(k)**H, where k = min(m,n).
Each H(i) has the form
   H(i) = I - tau * v * v**H
where tau is a complex scalar, and v is a complex vector with
v(n-k+i+1:n) = 0 and v(n-k+i) = 1; conjg(v(1:n-k+i-1)) is stored on
exit in A(m-k+i,1:n-k+i-1), and tau in TAU(i).

Authors: Univ. of Tennessee, Univ. of California Berkeley, Univ. of Colorado Denver, NAG Ltd.

Date: November 2011

RQDecompose(Int32, Int32, Span<Double>, Int32, Span<Double>, Int32)

Computes an RQ factorization of a complex M-by-N matrix A: A = R * Q.

C#
public override void RQDecompose(
	int m,
	int n,
	Span<double> a,
	int lda,
	Span<double> tau,
	out int info
)

Parameters

m  Int32
C#
M is INTEGER
The number of rows of the matrix A.  M >= 0.
n  Int32
C#
N is INTEGER
The number of columns of the matrix A.  N >= 0.
a  Span<Double>
C#
A is COMPLEX*16 array, dimension (LDA,N)
On entry, the M-by-N matrix A.
On exit,
if m <= n, the upper triangle of the subarray
A(1:m,n-m+1:n) contains the M-by-M upper triangular matrix R;
if m >= n, the elements on and above the (m-n)-th subdiagonal
contain the M-by-N upper trapezoidal matrix R;
the remaining elements, with the array TAU, represent the
unitary matrix Q as a product of min(m,n) elementary
reflectors (see Further Details).
lda  Int32
C#
LDA is INTEGER
The leading dimension of the array A.  LDA >= max(1,M).
tau  Span<Double>
C#
TAU is COMPLEX*16 array, dimension (min(M,N))
The scalar factors of the elementary reflectors (see Further
Details).
info  Int32
C#
INFO is INTEGER
= 0:  successful exit
< 0:  if INFO = -i, the i-th argument had an illegal value

Remarks

Further Details:

C#
The matrix Q is represented as a product of elementary reflectors
   Q = H(1)**H H(2)**H . . . H(k)**H, where k = min(m,n).
Each H(i) has the form
   H(i) = I - tau * v * v**H
where tau is a complex scalar, and v is a complex vector with
v(n-k+i+1:n) = 0 and v(n-k+i) = 1; conjg(v(1:n-k+i-1)) is stored on
exit in A(m-k+i,1:n-k+i-1), and tau in TAU(i).

Authors: Univ. of Tennessee, Univ. of California Berkeley, Univ. of Colorado Denver, NAG Ltd.

Date: November 2011

See Also