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
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
|
/* zupgtr.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"
/* Subroutine */ int zupgtr_(char *uplo, integer *n, doublecomplex *ap,
doublecomplex *tau, doublecomplex *q, integer *ldq, doublecomplex *
work, integer *info)
{
/* System generated locals */
integer q_dim1, q_offset, i__1, i__2, i__3, i__4;
/* Local variables */
integer i__, j, ij;
extern logical lsame_(char *, char *);
integer iinfo;
logical upper;
extern /* Subroutine */ int zung2l_(integer *, integer *, integer *,
doublecomplex *, integer *, doublecomplex *, doublecomplex *,
integer *), zung2r_(integer *, integer *, integer *,
doublecomplex *, integer *, doublecomplex *, doublecomplex *,
integer *), xerbla_(char *, integer *);
/* -- LAPACK routine (version 3.2) -- */
/* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
/* November 2006 */
/* .. Scalar Arguments .. */
/* .. */
/* .. Array Arguments .. */
/* .. */
/* Purpose */
/* ======= */
/* ZUPGTR generates a complex unitary matrix Q which is defined as the */
/* product of n-1 elementary reflectors H(i) of order n, as returned by */
/* ZHPTRD using packed storage: */
/* if UPLO = 'U', Q = H(n-1) . . . H(2) H(1), */
/* if UPLO = 'L', Q = H(1) H(2) . . . H(n-1). */
/* Arguments */
/* ========= */
/* UPLO (input) CHARACTER*1 */
/* = 'U': Upper triangular packed storage used in previous */
/* call to ZHPTRD; */
/* = 'L': Lower triangular packed storage used in previous */
/* call to ZHPTRD. */
/* N (input) INTEGER */
/* The order of the matrix Q. N >= 0. */
/* AP (input) COMPLEX*16 array, dimension (N*(N+1)/2) */
/* The vectors which define the elementary reflectors, as */
/* returned by ZHPTRD. */
/* TAU (input) COMPLEX*16 array, dimension (N-1) */
/* TAU(i) must contain the scalar factor of the elementary */
/* reflector H(i), as returned by ZHPTRD. */
/* Q (output) COMPLEX*16 array, dimension (LDQ,N) */
/* The N-by-N unitary matrix Q. */
/* LDQ (input) INTEGER */
/* The leading dimension of the array Q. LDQ >= max(1,N). */
/* WORK (workspace) COMPLEX*16 array, dimension (N-1) */
/* INFO (output) INTEGER */
/* = 0: successful exit */
/* < 0: if INFO = -i, the i-th argument had an illegal value */
/* ===================================================================== */
/* .. Parameters .. */
/* .. */
/* .. Local Scalars .. */
/* .. */
/* .. External Functions .. */
/* .. */
/* .. External Subroutines .. */
/* .. */
/* .. Intrinsic Functions .. */
/* .. */
/* .. Executable Statements .. */
/* Test the input arguments */
/* Parameter adjustments */
--ap;
--tau;
q_dim1 = *ldq;
q_offset = 1 + q_dim1;
q -= q_offset;
--work;
/* Function Body */
*info = 0;
upper = lsame_(uplo, "U");
if (! upper && ! lsame_(uplo, "L")) {
*info = -1;
} else if (*n < 0) {
*info = -2;
} else if (*ldq < max(1,*n)) {
*info = -6;
}
if (*info != 0) {
i__1 = -(*info);
xerbla_("ZUPGTR", &i__1);
return 0;
}
/* Quick return if possible */
if (*n == 0) {
return 0;
}
if (upper) {
/* Q was determined by a call to ZHPTRD with UPLO = 'U' */
/* Unpack the vectors which define the elementary reflectors and */
/* set the last row and column of Q equal to those of the unit */
/* matrix */
ij = 2;
i__1 = *n - 1;
for (j = 1; j <= i__1; ++j) {
i__2 = j - 1;
for (i__ = 1; i__ <= i__2; ++i__) {
i__3 = i__ + j * q_dim1;
i__4 = ij;
q[i__3].r = ap[i__4].r, q[i__3].i = ap[i__4].i;
++ij;
/* L10: */
}
ij += 2;
i__2 = *n + j * q_dim1;
q[i__2].r = 0., q[i__2].i = 0.;
/* L20: */
}
i__1 = *n - 1;
for (i__ = 1; i__ <= i__1; ++i__) {
i__2 = i__ + *n * q_dim1;
q[i__2].r = 0., q[i__2].i = 0.;
/* L30: */
}
i__1 = *n + *n * q_dim1;
q[i__1].r = 1., q[i__1].i = 0.;
/* Generate Q(1:n-1,1:n-1) */
i__1 = *n - 1;
i__2 = *n - 1;
i__3 = *n - 1;
zung2l_(&i__1, &i__2, &i__3, &q[q_offset], ldq, &tau[1], &work[1], &
iinfo);
} else {
/* Q was determined by a call to ZHPTRD with UPLO = 'L'. */
/* Unpack the vectors which define the elementary reflectors and */
/* set the first row and column of Q equal to those of the unit */
/* matrix */
i__1 = q_dim1 + 1;
q[i__1].r = 1., q[i__1].i = 0.;
i__1 = *n;
for (i__ = 2; i__ <= i__1; ++i__) {
i__2 = i__ + q_dim1;
q[i__2].r = 0., q[i__2].i = 0.;
/* L40: */
}
ij = 3;
i__1 = *n;
for (j = 2; j <= i__1; ++j) {
i__2 = j * q_dim1 + 1;
q[i__2].r = 0., q[i__2].i = 0.;
i__2 = *n;
for (i__ = j + 1; i__ <= i__2; ++i__) {
i__3 = i__ + j * q_dim1;
i__4 = ij;
q[i__3].r = ap[i__4].r, q[i__3].i = ap[i__4].i;
++ij;
/* L50: */
}
ij += 2;
/* L60: */
}
if (*n > 1) {
/* Generate Q(2:n,2:n) */
i__1 = *n - 1;
i__2 = *n - 1;
i__3 = *n - 1;
zung2r_(&i__1, &i__2, &i__3, &q[(q_dim1 << 1) + 2], ldq, &tau[1],
&work[1], &iinfo);
}
}
return 0;
/* End of ZUPGTR */
} /* zupgtr_ */
|
