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
|
/* lapack/double/dzsum1.f -- translated by f2c (version 20090411).
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
*/
#ifdef __cplusplus
extern "C" {
#endif
#include "v3p_netlib.h"
/*< DOUBLE PRECISION FUNCTION DZSUM1( N, CX, INCX ) >*/
doublereal dzsum1_(integer *n, doublecomplex *cx, integer *incx)
{
/* System generated locals */
integer i__1, i__2;
doublereal ret_val;
/* Builtin functions */
double z_abs(doublecomplex *);
/* Local variables */
integer i__, nincx;
doublereal stemp;
/* -- LAPACK auxiliary routine (version 3.2) -- */
/* -- LAPACK is a software package provided by Univ. of Tennessee, -- */
/* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- */
/* November 2006 */
/* .. Scalar Arguments .. */
/*< INTEGER INCX, N >*/
/* .. */
/* .. Array Arguments .. */
/*< COMPLEX*16 CX( * ) >*/
/* .. */
/* Purpose */
/* ======= */
/* DZSUM1 takes the sum of the absolute values of a complex */
/* vector and returns a double precision result. */
/* Based on DZASUM from the Level 1 BLAS. */
/* The change is to use the 'genuine' absolute value. */
/* Contributed by Nick Higham for use with ZLACON. */
/* Arguments */
/* ========= */
/* N (input) INTEGER */
/* The number of elements in the vector CX. */
/* CX (input) COMPLEX*16 array, dimension (N) */
/* The vector whose elements will be summed. */
/* INCX (input) INTEGER */
/* The spacing between successive values of CX. INCX > 0. */
/* ===================================================================== */
/* .. Local Scalars .. */
/*< INTEGER I, NINCX >*/
/*< DOUBLE PRECISION STEMP >*/
/* .. */
/* .. Intrinsic Functions .. */
/*< INTRINSIC ABS >*/
/* .. */
/* .. Executable Statements .. */
/*< DZSUM1 = 0.0D0 >*/
/* Parameter adjustments */
--cx;
/* Function Body */
ret_val = 0.;
/*< STEMP = 0.0D0 >*/
stemp = 0.;
/*< >*/
if (*n <= 0) {
return ret_val;
}
/*< >*/
if (*incx == 1) {
goto L20;
}
/* CODE FOR INCREMENT NOT EQUAL TO 1 */
/*< NINCX = N*INCX >*/
nincx = *n * *incx;
/*< DO 10 I = 1, NINCX, INCX >*/
i__1 = nincx;
i__2 = *incx;
for (i__ = 1; i__2 < 0 ? i__ >= i__1 : i__ <= i__1; i__ += i__2) {
/* NEXT LINE MODIFIED. */
/*< STEMP = STEMP + ABS( CX( I ) ) >*/
stemp += z_abs(&cx[i__]);
/*< 10 CONTINUE >*/
/* L10: */
}
/*< DZSUM1 = STEMP >*/
ret_val = stemp;
/*< RETURN >*/
return ret_val;
/* CODE FOR INCREMENT EQUAL TO 1 */
/*< 20 CONTINUE >*/
L20:
/*< DO 30 I = 1, N >*/
i__2 = *n;
for (i__ = 1; i__ <= i__2; ++i__) {
/* NEXT LINE MODIFIED. */
/*< STEMP = STEMP + ABS( CX( I ) ) >*/
stemp += z_abs(&cx[i__]);
/*< 30 CONTINUE >*/
/* L30: */
}
/*< DZSUM1 = STEMP >*/
ret_val = stemp;
/*< RETURN >*/
return ret_val;
/* End of DZSUM1 */
/*< END >*/
} /* dzsum1_ */
#ifdef __cplusplus
}
#endif
|
