lsst.daf.base  16.0-10-g1758552
DateTime.h
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1 // -*- lsst-c++ -*-
2 
3 /*
4  * LSST Data Management System
5  * Copyright 2008, 2009, 2010 LSST Corporation.
6  *
7  * This product includes software developed by the
8  * LSST Project (http://www.lsst.org/).
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24 
25 #ifndef LSST_DAF_BASE_DATETIME_H
26 #define LSST_DAF_BASE_DATETIME_H
27 
44 #include <cstdint>
45 #include <ctime>
46 #include <limits>
47 #include <sys/time.h>
48 #include <string>
49 
50 #include "lsst/base.h"
51 #include "lsst/pex/exceptions.h"
52 
53 // Forward declaration of the boost::serialization::access class.
54 namespace boost {
55 namespace serialization {
56 class access;
57 }
58 } // namespace boost
59 
60 namespace lsst {
61 namespace daf {
62 namespace base {
63 
65 public:
66  enum DateSystem { JD = 0, MJD, EPOCH };
67  enum Timescale {
68  TAI = 5,
69  UTC,
70  TT
71  }; // use values that do not overlap DateSystem
72  // to avoid confusing one for the other in Python
73  // an invalid DateTime has _nsec == invalid_nsecs
74  constexpr static long long invalid_nsecs = std::numeric_limits<std::int64_t>::min();
75 
79  explicit DateTime();
80 
90  explicit DateTime(long long nsecs, Timescale scale = TAI);
91 
100  explicit DateTime(double date, DateSystem system = MJD, Timescale scale = TAI);
101 
115  DateTime(int year, int month, int day, int hr, int min, int sec, Timescale scale = TAI);
116 
133  explicit DateTime(std::string const& iso8601, Timescale scale);
134 
145  long long nsecs(Timescale scale = TAI) const;
146 
156  double get(DateSystem system = MJD, Timescale scale = TAI) const;
157 
168  std::string toString(Timescale scale) const;
169 
177  struct tm gmtime(Timescale scale) const;
178 
187  struct timespec timespec(Timescale scale) const;
188 
197  struct timeval timeval(Timescale scale) const;
198 
202  bool isValid() const { return _nsecs != DateTime::invalid_nsecs; };
203 
204  bool operator==(DateTime const& rhs) const;
205 
210  static DateTime now(void);
211 
220  static void initializeLeapSeconds(std::string const& leapString);
221 
222 private:
223  long long _nsecs;
224 
226  void _assertValid() const {
227  if (!isValid()) {
228  throw LSST_EXCEPT(pex::exceptions::RuntimeError, "DateTime not valid");
229  }
230  }
231 
239  double _getMjd(Timescale scale) const;
240 
248  double _getJd(Timescale scale) const;
249 
257  double _getEpoch(Timescale scale) const;
258 
266  void setNsecsFromMjd(double mjd, Timescale scale);
267 
275  void setNsecsFromJd(double jd, Timescale scale);
276 
284  void setNsecsFromEpoch(double epoch, Timescale scale);
285 
286  friend class boost::serialization::access;
287 
294  template <class Archive>
295  void serialize(Archive ar, int const version) {
296  ar& _nsecs;
297  }
298 };
299 
300 } // namespace base
301 } // namespace daf
302 } // namespace lsst
303 
304 #endif
Class for handling dates/times, including MJD, UTC, and TAI.
Definition: DateTime.h:64
Definition: DateTime.h:54
STL class.
T min(T... args)
#define LSST_EXCEPT(type,...)
bool isValid() const
Is this date valid?
Definition: DateTime.h:202
#define LSST_EXPORT