LAPACK 3.12.0 LAPACK: Linear Algebra PACKage
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dlartv.f
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1*> \brief \b DLARTV applies a vector of plane rotations with real cosines and real sines to the elements of a pair of vectors.
2*
3* =========== DOCUMENTATION ===========
4*
5* Online html documentation available at
6* http://www.netlib.org/lapack/explore-html/
7*
8*> \htmlonly
10*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/dlartv.f">
11*> [TGZ]</a>
12*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/dlartv.f">
13*> [ZIP]</a>
14*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/dlartv.f">
15*> [TXT]</a>
16*> \endhtmlonly
17*
18* Definition:
19* ===========
20*
21* SUBROUTINE DLARTV( N, X, INCX, Y, INCY, C, S, INCC )
22*
23* .. Scalar Arguments ..
24* INTEGER INCC, INCX, INCY, N
25* ..
26* .. Array Arguments ..
27* DOUBLE PRECISION C( * ), S( * ), X( * ), Y( * )
28* ..
29*
30*
31*> \par Purpose:
32* =============
33*>
34*> \verbatim
35*>
36*> DLARTV applies a vector of real plane rotations to elements of the
37*> real vectors x and y. For i = 1,2,...,n
38*>
39*> ( x(i) ) := ( c(i) s(i) ) ( x(i) )
40*> ( y(i) ) ( -s(i) c(i) ) ( y(i) )
41*> \endverbatim
42*
43* Arguments:
44* ==========
45*
46*> \param[in] N
47*> \verbatim
48*> N is INTEGER
49*> The number of plane rotations to be applied.
50*> \endverbatim
51*>
52*> \param[in,out] X
53*> \verbatim
54*> X is DOUBLE PRECISION array,
55*> dimension (1+(N-1)*INCX)
56*> The vector x.
57*> \endverbatim
58*>
59*> \param[in] INCX
60*> \verbatim
61*> INCX is INTEGER
62*> The increment between elements of X. INCX > 0.
63*> \endverbatim
64*>
65*> \param[in,out] Y
66*> \verbatim
67*> Y is DOUBLE PRECISION array,
68*> dimension (1+(N-1)*INCY)
69*> The vector y.
70*> \endverbatim
71*>
72*> \param[in] INCY
73*> \verbatim
74*> INCY is INTEGER
75*> The increment between elements of Y. INCY > 0.
76*> \endverbatim
77*>
78*> \param[in] C
79*> \verbatim
80*> C is DOUBLE PRECISION array, dimension (1+(N-1)*INCC)
81*> The cosines of the plane rotations.
82*> \endverbatim
83*>
84*> \param[in] S
85*> \verbatim
86*> S is DOUBLE PRECISION array, dimension (1+(N-1)*INCC)
87*> The sines of the plane rotations.
88*> \endverbatim
89*>
90*> \param[in] INCC
91*> \verbatim
92*> INCC is INTEGER
93*> The increment between elements of C and S. INCC > 0.
94*> \endverbatim
95*
96* Authors:
97* ========
98*
99*> \author Univ. of Tennessee
100*> \author Univ. of California Berkeley
101*> \author Univ. of Colorado Denver
102*> \author NAG Ltd.
103*
104*> \ingroup lartv
105*
106* =====================================================================
107 SUBROUTINE dlartv( N, X, INCX, Y, INCY, C, S, INCC )
108*
109* -- LAPACK auxiliary routine --
110* -- LAPACK is a software package provided by Univ. of Tennessee, --
111* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
112*
113* .. Scalar Arguments ..
114 INTEGER INCC, INCX, INCY, N
115* ..
116* .. Array Arguments ..
117 DOUBLE PRECISION C( * ), S( * ), X( * ), Y( * )
118* ..
119*
120* =====================================================================
121*
122* .. Local Scalars ..
123 INTEGER I, IC, IX, IY
124 DOUBLE PRECISION XI, YI
125* ..
126* .. Executable Statements ..
127*
128 ix = 1
129 iy = 1
130 ic = 1
131 DO 10 i = 1, n
132 xi = x( ix )
133 yi = y( iy )
134 x( ix ) = c( ic )*xi + s( ic )*yi
135 y( iy ) = c( ic )*yi - s( ic )*xi
136 ix = ix + incx
137 iy = iy + incy
138 ic = ic + incc
139 10 CONTINUE
140 RETURN
141*
142* End of DLARTV
143*
144 END
subroutine dlartv(n, x, incx, y, incy, c, s, incc)
DLARTV applies a vector of plane rotations with real cosines and real sines to the elements of a pair...
Definition dlartv.f:108