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
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
|
/* zlarf.f -- translated by f2c (version 20061008).
You must link the resulting object file with libf2c:
on Microsoft Windows system, link with libf2c.lib;
on Linux or Unix systems, link with .../path/to/libf2c.a -lm
or, if you install libf2c.a in a standard place, with -lf2c -lm
-- in that order, at the end of the command line, as in
cc *.o -lf2c -lm
Source for libf2c is in /netlib/f2c/libf2c.zip, e.g.,
http://www.netlib.org/f2c/libf2c.zip
*/
#include "f2c.h"
#include "blaswrap.h"
/* Table of constant values */
static doublecomplex c_b1 = {1.,0.};
static doublecomplex c_b2 = {0.,0.};
static integer c__1 = 1;
/* Subroutine */ int zlarf_(char *side, integer *m, integer *n, doublecomplex
*v, integer *incv, doublecomplex *tau, doublecomplex *c__, integer *
ldc, doublecomplex *work)
{
/* System generated locals */
integer c_dim1, c_offset, i__1;
doublecomplex z__1;
/* Local variables */
integer i__;
logical applyleft;
extern logical lsame_(char *, char *);
integer lastc;
extern /* Subroutine */ int zgerc_(integer *, integer *, doublecomplex *,
doublecomplex *, integer *, doublecomplex *, integer *,
doublecomplex *, integer *), zgemv_(char *, integer *, integer *,
doublecomplex *, doublecomplex *, integer *, doublecomplex *,
integer *, doublecomplex *, doublecomplex *, integer *);
integer lastv;
extern integer ilazlc_(integer *, integer *, doublecomplex *, integer *),
ilazlr_(integer *, integer *, doublecomplex *, integer *);
/* -- LAPACK auxiliary routine (version 3.2) -- */
/* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
/* November 2006 */
/* .. Scalar Arguments .. */
/* .. */
/* .. Array Arguments .. */
/* .. */
/* Purpose */
/* ======= */
/* ZLARF applies a complex elementary reflector H to a complex M-by-N */
/* matrix C, from either the left or the right. H is represented in the */
/* form */
/* H = I - tau * v * v' */
/* where tau is a complex scalar and v is a complex vector. */
/* If tau = 0, then H is taken to be the unit matrix. */
/* To apply H' (the conjugate transpose of H), supply conjg(tau) instead */
/* tau. */
/* Arguments */
/* ========= */
/* SIDE (input) CHARACTER*1 */
/* = 'L': form H * C */
/* = 'R': form C * H */
/* M (input) INTEGER */
/* The number of rows of the matrix C. */
/* N (input) INTEGER */
/* The number of columns of the matrix C. */
/* V (input) COMPLEX*16 array, dimension */
/* (1 + (M-1)*abs(INCV)) if SIDE = 'L' */
/* or (1 + (N-1)*abs(INCV)) if SIDE = 'R' */
/* The vector v in the representation of H. V is not used if */
/* TAU = 0. */
/* INCV (input) INTEGER */
/* The increment between elements of v. INCV <> 0. */
/* TAU (input) COMPLEX*16 */
/* The value tau in the representation of H. */
/* C (input/output) COMPLEX*16 array, dimension (LDC,N) */
/* On entry, the M-by-N matrix C. */
/* On exit, C is overwritten by the matrix H * C if SIDE = 'L', */
/* or C * H if SIDE = 'R'. */
/* LDC (input) INTEGER */
/* The leading dimension of the array C. LDC >= max(1,M). */
/* WORK (workspace) COMPLEX*16 array, dimension */
/* (N) if SIDE = 'L' */
/* or (M) if SIDE = 'R' */
/* ===================================================================== */
/* .. Parameters .. */
/* .. */
/* .. Local Scalars .. */
/* .. */
/* .. External Subroutines .. */
/* .. */
/* .. External Functions .. */
/* .. */
/* .. Executable Statements .. */
/* Parameter adjustments */
--v;
c_dim1 = *ldc;
c_offset = 1 + c_dim1;
c__ -= c_offset;
--work;
/* Function Body */
applyleft = lsame_(side, "L");
lastv = 0;
lastc = 0;
if (tau->r != 0. || tau->i != 0.) {
/* Set up variables for scanning V. LASTV begins pointing to the end */
/* of V. */
if (applyleft) {
lastv = *m;
} else {
lastv = *n;
}
if (*incv > 0) {
i__ = (lastv - 1) * *incv + 1;
} else {
i__ = 1;
}
/* Look for the last non-zero row in V. */
for(;;) { /* while(complicated condition) */
i__1 = i__;
if (!(lastv > 0 && (v[i__1].r == 0. && v[i__1].i == 0.)))
break;
--lastv;
i__ -= *incv;
}
if (applyleft) {
/* Scan for the last non-zero column in C(1:lastv,:). */
lastc = ilazlc_(&lastv, n, &c__[c_offset], ldc);
} else {
/* Scan for the last non-zero row in C(:,1:lastv). */
lastc = ilazlr_(m, &lastv, &c__[c_offset], ldc);
}
}
/* Note that lastc.eq.0 renders the BLAS operations null; no special */
/* case is needed at this level. */
if (applyleft) {
/* Form H * C */
if (lastv > 0) {
/* w(1:lastc,1) := C(1:lastv,1:lastc)' * v(1:lastv,1) */
zgemv_("Conjugate transpose", &lastv, &lastc, &c_b1, &c__[
c_offset], ldc, &v[1], incv, &c_b2, &work[1], &c__1);
/* C(1:lastv,1:lastc) := C(...) - v(1:lastv,1) * w(1:lastc,1)' */
z__1.r = -tau->r, z__1.i = -tau->i;
zgerc_(&lastv, &lastc, &z__1, &v[1], incv, &work[1], &c__1, &c__[
c_offset], ldc);
}
} else {
/* Form C * H */
if (lastv > 0) {
/* w(1:lastc,1) := C(1:lastc,1:lastv) * v(1:lastv,1) */
zgemv_("No transpose", &lastc, &lastv, &c_b1, &c__[c_offset], ldc,
&v[1], incv, &c_b2, &work[1], &c__1);
/* C(1:lastc,1:lastv) := C(...) - w(1:lastc,1) * v(1:lastv,1)' */
z__1.r = -tau->r, z__1.i = -tau->i;
zgerc_(&lastc, &lastv, &z__1, &work[1], &c__1, &v[1], incv, &c__[
c_offset], ldc);
}
}
return 0;
/* End of ZLARF */
} /* zlarf_ */
|
