DSBEVRun Method

public void Run(
	string JOBZ,
	string UPLO,
	int N,
	int KD,
	ref double[] AB,
	int offset_ab,
	int LDAB,
	ref double[] W,
	int offset_w,
	ref double[] Z,
	int offset_z,
	int LDZ,
	ref double[] WORK,
	int offset_work,
	ref int INFO
)

Public Sub Run ( 
	JOBZ As String,
	UPLO As String,
	N As Integer,
	KD As Integer,
	ByRef AB As Double(),
	offset_ab As Integer,
	LDAB As Integer,
	ByRef W As Double(),
	offset_w As Integer,
	ByRef Z As Double(),
	offset_z As Integer,
	LDZ As Integer,
	ByRef WORK As Double(),
	offset_work As Integer,
	ByRef INFO As Integer
)

Parameters

JOBZ  String

(input) CHARACTER*1 = 'N': Compute eigenvalues only; = 'V': Compute eigenvalues and eigenvectors.

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.

KD  Int32

(input) INTEGER The number of superdiagonals of the matrix A if UPLO = 'U', or the number of subdiagonals if UPLO = 'L'. KD .GE. 0.

AB  Double

(input/output) DOUBLE PRECISION array, dimension (LDAB, N) On entry, the upper or lower triangle of the symmetric band matrix A, stored in the first KD+1 rows of the array. The j-th column of A is stored in the j-th column of the array AB as follows: if UPLO = 'U', AB(kd+1+i-j,j) = A(i,j) for max(1,j-kd).LE.i.LE.j; if UPLO = 'L', AB(1+i-j,j) = A(i,j) for j.LE.i.LE.min(n,j+kd). On exit, AB is overwritten by values generated during the reduction to tridiagonal form. If UPLO = 'U', the first superdiagonal and the diagonal of the tridiagonal matrix T are returned in rows KD and KD+1 of AB, and if UPLO = 'L', the diagonal and first subdiagonal of T are returned in the first two rows of AB.

offset_ab  Int32

 

LDAB  Int32

(input) INTEGER The leading dimension of the array AB. LDAB .GE. KD + 1.

W  Double

(output) DOUBLE PRECISION array, dimension (N) If INFO = 0, the eigenvalues in ascending order.

offset_w  Int32

 

Z  Double

(output) DOUBLE PRECISION array, dimension (LDZ, N) If JOBZ = 'V', then if INFO = 0, Z contains the orthonormal eigenvectors of the matrix A, with the i-th column of Z holding the eigenvector associated with W(i). If JOBZ = 'N', then Z is not referenced.

offset_z  Int32

 

LDZ  Int32

(input) INTEGER The leading dimension of the array Z. LDZ .GE. 1, and if JOBZ = 'V', LDZ .GE. max(1,N).

WORK  Double

(workspace) DOUBLE PRECISION array, dimension (max(1,3*N-2))

offset_work  Int32

 

INFO  Int32

(output) INTEGER = 0: successful exit .LT. 0: if INFO = -i, the i-th argument had an illegal value .GT. 0: if INFO = i, the algorithm failed to converge; i off-diagonal elements of an intermediate tridiagonal form did not converge to zero.

Reference