1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
|
*> \brief \b CROT applies a plane rotation with real cosine and complex sine to a pair of complex vectors.
*
* =========== DOCUMENTATION ===========
*
* Online html documentation available at
* http://www.netlib.org/lapack/explore-html/
*
*> \htmlonly
*> Download CROT + dependencies
*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/crot.f">
*> [TGZ]</a>
*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/crot.f">
*> [ZIP]</a>
*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/crot.f">
*> [TXT]</a>
*> \endhtmlonly
*
* Definition:
* ===========
*
* SUBROUTINE CROT( N, CX, INCX, CY, INCY, C, S )
*
* .. Scalar Arguments ..
* INTEGER INCX, INCY, N
* REAL C
* COMPLEX S
* ..
* .. Array Arguments ..
* COMPLEX CX( * ), CY( * )
* ..
*
*
*> \par Purpose:
* =============
*>
*> \verbatim
*>
*> 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.
*> \endverbatim
*
* Arguments:
* ==========
*
*> \param[in] N
*> \verbatim
*> N is INTEGER
*> The number of elements in the vectors CX and CY.
*> \endverbatim
*>
*> \param[in,out] CX
*> \verbatim
*> CX is COMPLEX array, dimension (N)
*> On input, the vector X.
*> On output, CX is overwritten with C*X + S*Y.
*> \endverbatim
*>
*> \param[in] INCX
*> \verbatim
*> INCX is INTEGER
*> The increment between successive values of CY. INCX <> 0.
*> \endverbatim
*>
*> \param[in,out] CY
*> \verbatim
*> CY is COMPLEX array, dimension (N)
*> On input, the vector Y.
*> On output, CY is overwritten with -CONJG(S)*X + C*Y.
*> \endverbatim
*>
*> \param[in] INCY
*> \verbatim
*> INCY is INTEGER
*> The increment between successive values of CY. INCX <> 0.
*> \endverbatim
*>
*> \param[in] C
*> \verbatim
*> C is REAL
*> \endverbatim
*>
*> \param[in] S
*> \verbatim
*> S is COMPLEX
*> C and S define a rotation
*> [ C S ]
*> [ -conjg(S) C ]
*> where C*C + S*CONJG(S) = 1.0.
*> \endverbatim
*
* Authors:
* ========
*
*> \author Univ. of Tennessee
*> \author Univ. of California Berkeley
*> \author Univ. of Colorado Denver
*> \author NAG Ltd.
*
*> \date September 2012
*
*> \ingroup complexOTHERauxiliary
*
* =====================================================================
SUBROUTINE CROT( N, CX, INCX, CY, INCY, C, S )
*
* -- LAPACK auxiliary routine (version 3.4.2) --
* -- LAPACK is a software package provided by Univ. of Tennessee, --
* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
* September 2012
*
* .. Scalar Arguments ..
INTEGER INCX, INCY, N
REAL C
COMPLEX S
* ..
* .. Array Arguments ..
COMPLEX CX( * ), CY( * )
* ..
*
* =====================================================================
*
* .. 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
|
