!>
!> DLARFY applies an elementary reflector, or Householder matrix, H,
!> to an n x n symmetric matrix C, from both the left and the right.
!>
!> H is represented in the form
!>
!>    H = I - tau * v * v'
!>
!> where  tau  is a scalar and  v  is a vector.
!>
!> If  tau  is  zero, then  H  is taken to be the unit matrix.
!> 

UPLO

!>          UPLO is CHARACTER*1
!>          Specifies whether the upper or lower triangular part of the
!>          symmetric matrix C is stored.
!>          = 'U':  Upper triangle
!>          = 'L':  Lower triangle
!> 

N

!>          N is INTEGER
!>          The number of rows and columns of the matrix C.  N >= 0.
!> 

V

!>          V is DOUBLE PRECISION array, dimension
!>                  (1 + (N-1)*abs(INCV))
!>          The vector v as described above.
!> 

INCV

!>          INCV is INTEGER
!>          The increment between successive elements of v.  INCV must
!>          not be zero.
!> 

TAU

!>          TAU is DOUBLE PRECISION
!>          The value tau as described above.
!> 

C

!>          C is DOUBLE PRECISION array, dimension (LDC, N)
!>          On entry, the matrix C.
!>          On exit, C is overwritten by H * C * H'.
!> 

LDC

!>          LDC is INTEGER
!>          The leading dimension of the array C.  LDC >= max( 1, N ).
!> 

WORK

!>          WORK is DOUBLE PRECISION array, dimension (N)
!> 

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