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dspev.f(3)				      LAPACK				       dspev.f(3)

NAME
       dspev.f -

SYNOPSIS
   Functions/Subroutines
       subroutine dspev (JOBZ, UPLO, N, AP, W, Z, LDZ, WORK, INFO)
	    DSPEV computes the eigenvalues and, optionally, the left and/or right eigenvectors
	   for OTHER matrices

Function/Subroutine Documentation
   subroutine dspev (characterJOBZ, characterUPLO, integerN, double precision, dimension( * )AP,
       double precision, dimension( * )W, double precision, dimension( ldz, * )Z, integerLDZ,
       double precision, dimension( * )WORK, integerINFO)
	DSPEV computes the eigenvalues and, optionally, the left and/or right eigenvectors for
       OTHER matrices

       Purpose:

	    DSPEV computes all the eigenvalues and, optionally, eigenvectors of a
	    real symmetric matrix A in packed storage.

       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.

	   AP

		     AP is DOUBLE PRECISION array, dimension (N*(N+1)/2)
		     On entry, the upper or lower triangle of the symmetric matrix
		     A, packed columnwise in a linear array.  The j-th column of A
		     is stored in the array AP as follows:
		     if UPLO = 'U', AP(i + (j-1)*j/2) = A(i,j) for 1<=i<=j;
		     if UPLO = 'L', AP(i + (j-1)*(2*n-j)/2) = A(i,j) for j<=i<=n.

		     On exit, AP is overwritten by values generated during the
		     reduction to tridiagonal form.  If UPLO = 'U', the diagonal
		     and first superdiagonal of the tridiagonal matrix T overwrite
		     the corresponding elements of A, and if UPLO = 'L', the
		     diagonal and first subdiagonal of T overwrite the
		     corresponding elements of A.

	   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 (3*N)

	   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 131 of file dspev.f.

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

Version 3.4.2				 Tue Sep 25 2012			       dspev.f(3)
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