DSYTRDRun Method

public void Run(
	string UPLO,
	int N,
	ref double[] A,
	int offset_a,
	int LDA,
	ref double[] D,
	int offset_d,
	ref double[] E,
	int offset_e,
	ref double[] TAU,
	int offset_tau,
	ref double[] WORK,
	int offset_work,
	int LWORK,
	ref int INFO
)

Public Sub Run ( 
	UPLO As String,
	N As Integer,
	ByRef A As Double(),
	offset_a As Integer,
	LDA As Integer,
	ByRef D As Double(),
	offset_d As Integer,
	ByRef E As Double(),
	offset_e As Integer,
	ByRef TAU As Double(),
	offset_tau As Integer,
	ByRef WORK As Double(),
	offset_work As Integer,
	LWORK As Integer,
	ByRef INFO As Integer
)

Parameters

UPLO  String

(input) CHARACTER*1 = 'U': Upper triangle of A is stored; = 'L': Lower triangle of A is stored.

N  Int32

(input) INTEGER The order of the matrix A. N .GE. 0.

A  Double

(input/output) DOUBLE PRECISION array, dimension (LDA,N) On entry, the symmetric matrix A. If UPLO = 'U', the leading N-by-N upper triangular part of A contains the upper triangular part of the matrix A, and the strictly lower triangular part of A is not referenced. If UPLO = 'L', the leading N-by-N lower triangular part of A contains the lower triangular part of the matrix A, and the strictly upper triangular part of A is not referenced. On exit, if UPLO = 'U', the diagonal and first superdiagonal of A are overwritten by the corresponding elements of the tridiagonal matrix T, and the elements above the first superdiagonal, with the array TAU, represent the orthogonal matrix Q as a product of elementary reflectors; if UPLO = 'L', the diagonal and first subdiagonal of A are over- written by the corresponding elements of the tridiagonal matrix T, and the elements below the first subdiagonal, with the array TAU, represent the orthogonal matrix Q as a product of elementary reflectors. See Further Details.

offset_a  Int32

 

LDA  Int32

(input) INTEGER The leading dimension of the array A. LDA .GE. max(1,N).

D  Double

(output) DOUBLE PRECISION array, dimension (N) The diagonal elements of the tridiagonal matrix T: D(i) = A(i,i).

offset_d  Int32

 

E  Double

(output) DOUBLE PRECISION array, dimension (N-1) The off-diagonal elements of the tridiagonal matrix T: E(i) = A(i,i+1) if UPLO = 'U', E(i) = A(i+1,i) if UPLO = 'L'.

offset_e  Int32

 

TAU  Double

(output) DOUBLE PRECISION array, dimension (N-1) The scalar factors of the elementary reflectors (see Further Details).

offset_tau  Int32

 

WORK  Double

(workspace/output) DOUBLE PRECISION array, dimension (MAX(1,LWORK)) On exit, if INFO = 0, WORK(1) returns the optimal LWORK.

offset_work  Int32

 

LWORK  Int32

(input) INTEGER The dimension of the array WORK. LWORK .GE. 1. For optimum performance LWORK .GE. N*NB, where NB is the optimal blocksize. If LWORK = -1, then a workspace query is assumed; the routine only calculates the optimal size of the WORK array, returns this value as the first entry of the WORK array, and no error message related to LWORK is issued by XERBLA.

INFO  Int32

(output) INTEGER = 0: successful exit .LT. 0: if INFO = -i, the i-th argument had an illegal value

Reference