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Mise à jour de lapack vers la version 3.3.0.

    1:       SUBROUTINE DLAR2V( N, X, Y, Z, INCX, 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, N
   10: *     ..
   11: *     .. Array Arguments ..
   12:       DOUBLE PRECISION   C( * ), S( * ), X( * ), Y( * ), Z( * )
   13: *     ..
   14: *
   15: *  Purpose
   16: *  =======
   17: *
   18: *  DLAR2V applies a vector of real plane rotations from both sides to
   19: *  a sequence of 2-by-2 real symmetric matrices, defined by the elements
   20: *  of the vectors x, y and z. For i = 1,2,...,n
   21: *
   22: *     ( x(i)  z(i) ) := (  c(i)  s(i) ) ( x(i)  z(i) ) ( c(i) -s(i) )
   23: *     ( z(i)  y(i) )    ( -s(i)  c(i) ) ( z(i)  y(i) ) ( s(i)  c(i) )
   24: *
   25: *  Arguments
   26: *  =========
   27: *
   28: *  N       (input) INTEGER
   29: *          The number of plane rotations to be applied.
   30: *
   31: *  X       (input/output) DOUBLE PRECISION array,
   32: *                         dimension (1+(N-1)*INCX)
   33: *          The vector x.
   34: *
   35: *  Y       (input/output) DOUBLE PRECISION array,
   36: *                         dimension (1+(N-1)*INCX)
   37: *          The vector y.
   38: *
   39: *  Z       (input/output) DOUBLE PRECISION array,
   40: *                         dimension (1+(N-1)*INCX)
   41: *          The vector z.
   42: *
   43: *  INCX    (input) INTEGER
   44: *          The increment between elements of X, Y and Z. INCX > 0.
   45: *
   46: *  C       (input) DOUBLE PRECISION array, dimension (1+(N-1)*INCC)
   47: *          The cosines of the plane rotations.
   48: *
   49: *  S       (input) DOUBLE PRECISION array, dimension (1+(N-1)*INCC)
   50: *          The sines of the plane rotations.
   51: *
   52: *  INCC    (input) INTEGER
   53: *          The increment between elements of C and S. INCC > 0.
   54: *
   55: *  =====================================================================
   56: *
   57: *     .. Local Scalars ..
   58:       INTEGER            I, IC, IX
   59:       DOUBLE PRECISION   CI, SI, T1, T2, T3, T4, T5, T6, XI, YI, ZI
   60: *     ..
   61: *     .. Executable Statements ..
   62: *
   63:       IX = 1
   64:       IC = 1
   65:       DO 10 I = 1, N
   66:          XI = X( IX )
   67:          YI = Y( IX )
   68:          ZI = Z( IX )
   69:          CI = C( IC )
   70:          SI = S( IC )
   71:          T1 = SI*ZI
   72:          T2 = CI*ZI
   73:          T3 = T2 - SI*XI
   74:          T4 = T2 + SI*YI
   75:          T5 = CI*XI + T1
   76:          T6 = CI*YI - T1
   77:          X( IX ) = CI*T5 + SI*T4
   78:          Y( IX ) = CI*T6 - SI*T3
   79:          Z( IX ) = CI*T4 - SI*T5
   80:          IX = IX + INCX
   81:          IC = IC + INCC
   82:    10 CONTINUE
   83: *
   84: *     End of DLAR2V
   85: *
   86:       RETURN
   87:       END