rz_factor Interface

public interface rz_factor

Module Procedures

private pure subroutine rz_factor_dbl(a, tau, rz)

Factors an upper trapezoidal matrix by means of orthogonal transformations such that $A = R Z = (R 0) Z$ . $Z$ is an orthogonal matrix of dimension N-by-N, and $R$ is an M-by-M upper triangular matrix.

Arguments

Type	Intent	Optional	Attributes		Name
real(kind=real64),	intent(in),		dimension(:,:)	::	a	The M-by-N upper trapezoidal matrix to factor.
real(kind=real64),	intent(out),		allocatable, dimension(:)	::	tau	An M-element array used to store the scalar factors of the elementary reflectors.
real(kind=real64),	intent(out),		allocatable, dimension(:,:)	::	rz	The leading M-by-M upper triangular part of this matrix contains the upper triangular matrix $R$ , and elements N-L+1 to N of the first M rows, with the array tau, represent the orthogonal matrix $Z$ as a product of M elementary reflectors.

private pure subroutine rz_factor_cmplx(a, tau, rz)

Factors an upper trapezoidal matrix by means of orthogonal transformations such that $A = R Z = (R 0) Z$ . $Z$ is an orthogonal matrix of dimension N-by-N, and $R$ is an M-by-M upper triangular matrix.

Arguments

Type	Intent	Optional	Attributes		Name
complex(kind=real64),	intent(in),		dimension(:,:)	::	a	On input, the M-by-N upper trapezoidal matrix to factor. On output, the leading M-by-M upper triangular part of the matrix contains the upper triangular matrix $R$ , and elements N-L+1 to N of the first M rows of $A$ , with the array tau, represent the orthogonal matrix $Z$ as a product of M elementary reflectors.
complex(kind=real64),	intent(out),		allocatable, dimension(:)	::	tau	An M-element array used to store the scalar factors of the elementary reflectors.
complex(kind=real64),	intent(out),		allocatable, dimension(:,:)	::	rz	The leading M-by-M upper triangular part of this matrix contains the upper triangular matrix $R$ , and elements N-L+1 to N of the first M rows, with the array tau, represent the orthogonal matrix $Z$ as a product of M elementary reflectors.