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Annotation of rpl/lapack/lapack/dlartv.f, revision 1.2

1.1       bertrand    1:       SUBROUTINE DLARTV( N, X, INCX, Y, INCY, C, S, INCC )
                      2: *
                      3: *  -- LAPACK auxiliary routine (version 3.2) --
                      4: *  -- LAPACK is a software package provided by Univ. of Tennessee,    --
                      5: *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
                      6: *     November 2006
                      7: *
                      8: *     .. Scalar Arguments ..
                      9:       INTEGER            INCC, INCX, INCY, N
                     10: *     ..
                     11: *     .. Array Arguments ..
                     12:       DOUBLE PRECISION   C( * ), S( * ), X( * ), Y( * )
                     13: *     ..
                     14: *
                     15: *  Purpose
                     16: *  =======
                     17: *
                     18: *  DLARTV applies a vector of real plane rotations to elements of the
                     19: *  real vectors x and y. For i = 1,2,...,n
                     20: *
                     21: *     ( x(i) ) := (  c(i)  s(i) ) ( x(i) )
                     22: *     ( y(i) )    ( -s(i)  c(i) ) ( y(i) )
                     23: *
                     24: *  Arguments
                     25: *  =========
                     26: *
                     27: *  N       (input) INTEGER
                     28: *          The number of plane rotations to be applied.
                     29: *
                     30: *  X       (input/output) DOUBLE PRECISION array,
                     31: *                         dimension (1+(N-1)*INCX)
                     32: *          The vector x.
                     33: *
                     34: *  INCX    (input) INTEGER
                     35: *          The increment between elements of X. INCX > 0.
                     36: *
                     37: *  Y       (input/output) DOUBLE PRECISION array,
                     38: *                         dimension (1+(N-1)*INCY)
                     39: *          The vector y.
                     40: *
                     41: *  INCY    (input) INTEGER
                     42: *          The increment between elements of Y. INCY > 0.
                     43: *
                     44: *  C       (input) DOUBLE PRECISION array, dimension (1+(N-1)*INCC)
                     45: *          The cosines of the plane rotations.
                     46: *
                     47: *  S       (input) DOUBLE PRECISION array, dimension (1+(N-1)*INCC)
                     48: *          The sines of the plane rotations.
                     49: *
                     50: *  INCC    (input) INTEGER
                     51: *          The increment between elements of C and S. INCC > 0.
                     52: *
                     53: *  =====================================================================
                     54: *
                     55: *     .. Local Scalars ..
                     56:       INTEGER            I, IC, IX, IY
                     57:       DOUBLE PRECISION   XI, YI
                     58: *     ..
                     59: *     .. Executable Statements ..
                     60: *
                     61:       IX = 1
                     62:       IY = 1
                     63:       IC = 1
                     64:       DO 10 I = 1, N
                     65:          XI = X( IX )
                     66:          YI = Y( IY )
                     67:          X( IX ) = C( IC )*XI + S( IC )*YI
                     68:          Y( IY ) = C( IC )*YI - S( IC )*XI
                     69:          IX = IX + INCX
                     70:          IY = IY + INCY
                     71:          IC = IC + INCC
                     72:    10 CONTINUE
                     73:       RETURN
                     74: *
                     75: *     End of DLARTV
                     76: *
                     77:       END