debian man page for dsbev

dsbev.f(3)							      LAPACK								dsbev.f(3)

NAME
       dsbev.f -

SYNOPSIS
   Functions/Subroutines
       subroutine dsbev (JOBZ, UPLO, N, KD, AB, LDAB, W, Z, LDZ, WORK, INFO)
	    DSBEV computes the eigenvalues and, optionally, the left and/or right eigenvectors for OTHER matrices

Function/Subroutine Documentation
   subroutine dsbev (characterJOBZ, characterUPLO, integerN, integerKD, double precision, dimension( ldab, * )AB, integerLDAB, double precision,
       dimension( * )W, double precision, dimension( ldz, * )Z, integerLDZ, double precision, dimension( * )WORK, integerINFO)
	DSBEV computes the eigenvalues and, optionally, the left and/or right eigenvectors for OTHER matrices

       Purpose:

	    DSBEV computes all the eigenvalues and, optionally, eigenvectors of
	    a real symmetric band matrix A.

       Parameters:
	   JOBZ

		     JOBZ is CHARACTER*1
		     = 'N':  Compute eigenvalues only;
		     = 'V':  Compute eigenvalues and eigenvectors.

	   UPLO

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

	   N

		     N is INTEGER
		     The order of the matrix A.  N >= 0.

	   KD

		     KD is INTEGER
		     The number of superdiagonals of the matrix A if UPLO = 'U',
		     or the number of subdiagonals if UPLO = 'L'.  KD >= 0.

	   AB

		     AB is 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)<=i<=j;
		     if UPLO = 'L', AB(1+i-j,j)    = A(i,j) for j<=i<=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.

	   LDAB

		     LDAB is INTEGER
		     The leading dimension of the array AB.  LDAB >= KD + 1.

	   W

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

	   Z

		     Z is 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.

	   LDZ

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

	   WORK

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

	   INFO

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

       Author:
	   Univ. of Tennessee

	   Univ. of California Berkeley

	   Univ. of Colorado Denver

	   NAG Ltd.

       Date:
	   November 2011

       Definition at line 146 of file dsbev.f.

Author
       Generated automatically by Doxygen for LAPACK from the source code.

Version 3.4.1							  Sun May 26 2013							dsbev.f(3)