```      SUBROUTINE CROT( N, CX, INCX, CY, INCY, C, S )
*
*  -- LAPACK auxiliary routine (version 3.1) --
*     Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd..
*     November 2006
*
*     .. Scalar Arguments ..
INTEGER            INCX, INCY, N
REAL               C
COMPLEX            S
*     ..
*     .. Array Arguments ..
COMPLEX            CX( * ), CY( * )
*     ..
*
*  Purpose
*  =======
*
*  CROT   applies a plane rotation, where the cos (C) is real and the
*  sin (S) is complex, and the vectors CX and CY are complex.
*
*  Arguments
*  =========
*
*  N       (input) INTEGER
*          The number of elements in the vectors CX and CY.
*
*  CX      (input/output) COMPLEX array, dimension (N)
*          On input, the vector X.
*          On output, CX is overwritten with C*X + S*Y.
*
*  INCX    (input) INTEGER
*          The increment between successive values of CY.  INCX <> 0.
*
*  CY      (input/output) COMPLEX array, dimension (N)
*          On input, the vector Y.
*          On output, CY is overwritten with -CONJG(S)*X + C*Y.
*
*  INCY    (input) INTEGER
*          The increment between successive values of CY.  INCX <> 0.
*
*  C       (input) REAL
*  S       (input) COMPLEX
*          C and S define a rotation
*             [  C          S  ]
*             [ -conjg(S)   C  ]
*          where C*C + S*CONJG(S) = 1.0.
*
* =====================================================================
*
*     .. Local Scalars ..
INTEGER            I, IX, IY
COMPLEX            STEMP
*     ..
*     .. Intrinsic Functions ..
INTRINSIC          CONJG
*     ..
*     .. Executable Statements ..
*
IF( N.LE.0 )
\$   RETURN
IF( INCX.EQ.1 .AND. INCY.EQ.1 )
\$   GO TO 20
*
*     Code for unequal increments or equal increments not equal to 1
*
IX = 1
IY = 1
IF( INCX.LT.0 )
\$   IX = ( -N+1 )*INCX + 1
IF( INCY.LT.0 )
\$   IY = ( -N+1 )*INCY + 1
DO 10 I = 1, N
STEMP = C*CX( IX ) + S*CY( IY )
CY( IY ) = C*CY( IY ) - CONJG( S )*CX( IX )
CX( IX ) = STEMP
IX = IX + INCX
IY = IY + INCY
10 CONTINUE
RETURN
*
*     Code for both increments equal to 1
*
20 CONTINUE
DO 30 I = 1, N
STEMP = C*CX( I ) + S*CY( I )
CY( I ) = C*CY( I ) - CONJG( S )*CX( I )
CX( I ) = STEMP
30 CONTINUE
RETURN
END

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