grass  7.8.6
About: GRASS (Geographic Resources Analysis Support System) is a raster- and vector-based GIS, image processing system, graphics production system and spatial modeling system.
  Fossies Dox: grass-7.8.6.tar.gz  ("unofficial" and yet experimental doxygen-generated source code documentation)  

sign.c
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1/*
2 * Copyright (C) 1995. Bill Brown <brown@gis.uiuc.edu> & Michael Shapiro
3 *
4 * This program is free software under the GPL (>=v2)
5 * Read the file GPL.TXT coming with GRASS for details.
6 */
7#include <grass/datetime.h>
8
9
10/*!
11 * \brief
12 *
13 * Returns:
14 * 1 if the Datetime is positive
15 * 0 otherwise
16 *
17 * \param dt
18 * \return int
19 */
20
22{
23 return dt->positive != 0;
24}
25
26/*!
27 * \brief
28 *
29 * Returns:
30 * 1 if the DateTime is negative
31 * 0 otherwise
32 *
33 * \param dt
34 * \return int
35 */
36
38{
39 return dt->positive == 0;
40}
41
42
43/*!
44 * \brief
45 *
46 * Makes the DateTime positive. (A.D. for ABSOLUTE DateTimes)
47 *
48 * \param dt
49 * \return void
50 */
51
53{
54 dt->positive = 1;
55}
56
57
58/*!
59 * \brief
60 *
61 * Makes the DateTime negative. (B.C. for ABSOLUTE DateTimes)
62 *
63 * \param dt
64 * \return void
65 */
66
68{
69 dt->positive = 0;
70}
71
72
73/*!
74 * \brief
75 *
76 * \param dt
77 * \return void
78 */
79
81{
82 dt->positive = !dt->positive;
83}
int datetime_is_negative(const DateTime *dt)
Returns: 1 if the DateTime is negative 0 otherwise.
Definition: sign.c:37
int datetime_is_positive(const DateTime *dt)
Returns: 1 if the Datetime is positive 0 otherwise.
Definition: sign.c:21
void datetime_set_negative(DateTime *dt)
Makes the DateTime negative. (B.C. for ABSOLUTE DateTimes)
Definition: sign.c:67
void datetime_set_positive(DateTime *dt)
Makes the DateTime positive. (A.D. for ABSOLUTE DateTimes)
Definition: sign.c:52
void datetime_invert_sign(DateTime *dt)
Definition: sign.c:80
int positive
Definition: datetime.h:25