Time and date functions.
Header: #include <mrpt/system/datetime.h>
.
Library: [mrpt-system]
Defines types and functions to handle cross-platform timestamps. The basic type is mrpt::system::TTimeStamp, representing a high-resolution (100ns) Clock::time_point, compatible with all C++11 std::chrono functions.
There are also functions to convert forth and back to a double
representation of timestamps: numbers just like UNIX epoch timestamps but with decimals for the fractionary part of seconds.
// typedefs typedef mrpt::Clock::time_point mrpt::system::TTimeStamp; // structs struct mrpt::system::TTimeParts; // global functions const TTimeStamp& mrpt::system::InvalidTimeStamp(); mrpt::system::TTimeStamp mrpt::system::buildTimestampFromParts(const mrpt::system::TTimeParts& p); mrpt::system::TTimeStamp mrpt::system::buildTimestampFromPartsLocalTime(const mrpt::system::TTimeParts& p); void mrpt::system::timestampToParts(TTimeStamp t, TTimeParts& p, bool localTime = false); mrpt::system::TTimeStamp mrpt::system::getCurrentTime(); mrpt::system::TTimeStamp mrpt::system::now(); mrpt::system::TTimeStamp mrpt::system::time_tToTimestamp(const double t); mrpt::system::TTimeStamp mrpt::system::time_tToTimestamp(const time_t& t); double mrpt::system::timestampTotime_t(const mrpt::system::TTimeStamp t); double mrpt::system::timestampToDouble(const mrpt::system::TTimeStamp t); double mrpt::system::timeDifference(const mrpt::system::TTimeStamp& t_first, const mrpt::system::TTimeStamp& t_later); double mrpt::system::now_double(); mrpt::system::TTimeStamp mrpt::system::timestampAdd(const mrpt::system::TTimeStamp tim, const double num_seconds); std::string mrpt::system::formatTimeInterval(const double timeSeconds); std::string mrpt::system::dateTimeToString(const mrpt::system::TTimeStamp t); std::string mrpt::system::dateTimeLocalToString(const mrpt::system::TTimeStamp t); std::string mrpt::system::dateToString(const mrpt::system::TTimeStamp t); double mrpt::system::extractDayTimeFromTimestamp(const mrpt::system::TTimeStamp t); std::string mrpt::system::timeToString(const mrpt::system::TTimeStamp t); std::string mrpt::system::timeLocalToString(const mrpt::system::TTimeStamp t, unsigned int secondFractionDigits = 6); std::string mrpt::system::intervalFormat(const double seconds); std::ostream& mrpt::system::operator << (std::ostream& o, const TTimeStamp& t); // macros #define INVALID_TIMESTAMP
Typedefs
typedef mrpt::Clock::time_point mrpt::system::TTimeStamp
A system independent time type, it holds the the number of 100-nanosecond intervals since January 1, 1601 (UTC) as a mrpt::Clock::time_point (uint64_t).
See also:
system::getCurrentTime, system::timeDifference, INVALID_TIMESTAMP, TTimeParts
Global Functions
const TTimeStamp& mrpt::system::InvalidTimeStamp()
Required to ensure INVALID_TIMESTAMP returns a “const T&”.
(New in MRPT 2.3.3)
mrpt::system::TTimeStamp mrpt::system::buildTimestampFromParts(const mrpt::system::TTimeParts& p)
Builds a timestamp from the parts (Parts are in UTC)
See also:
mrpt::system::TTimeStamp mrpt::system::buildTimestampFromPartsLocalTime(const mrpt::system::TTimeParts& p)
Builds a timestamp from the parts (Parts are in local time)
See also:
timestampToParts, buildTimestampFromParts
void mrpt::system::timestampToParts(TTimeStamp t, TTimeParts& p, bool localTime = false)
Gets the individual parts of a date/time (days, hours, minutes, seconds) - UTC time or local time.
See also:
mrpt::system::TTimeStamp mrpt::system::getCurrentTime()
Returns the current (UTC) system time.
See also:
mrpt::system::TTimeStamp mrpt::system::now()
A shortcut for system::getCurrentTime.
See also:
mrpt::system::TTimeStamp mrpt::system::time_tToTimestamp(const double t)
Transform from standard “time_t” (actually a double number, it can contain fractions of seconds) to TTimeStamp.
See also:
mrpt::system::TTimeStamp mrpt::system::time_tToTimestamp(const time_t& t)
Transform from standard “time_t” to TTimeStamp.
See also:
double mrpt::system::timestampTotime_t(const mrpt::system::TTimeStamp t)
Transform from TTimeStamp to standard “time_t” (actually a double number, it can contain fractions of seconds).
See also:
double mrpt::system::timestampToDouble(const mrpt::system::TTimeStamp t)
Transform from TTimeStamp to standard “time_t” (actually a double number, it can contain fractions of seconds).
This function is just an (inline) alias of timestampTotime_t(), with a more significant name.
See also:
double mrpt::system::timeDifference(const mrpt::system::TTimeStamp& t_first, const mrpt::system::TTimeStamp& t_later)
Returns the time difference from t1 to t2 (positive if t2 is posterior to t1), in seconds
double mrpt::system::now_double()
Returns the current time, as a double
(fractional version of time_t) instead of a TTimeStamp
.
See also:
mrpt::system::TTimeStamp mrpt::system::timestampAdd(const mrpt::system::TTimeStamp tim, const double num_seconds)
Shifts a timestamp the given amount of seconds (>0: forwards in time, <0: backwards)
std::string mrpt::system::formatTimeInterval(const double timeSeconds)
Returns a formated string with the given time difference (passed as the number of seconds), as a string [H]H:MM:SS.MILLISECONDS.
See also:
std::string mrpt::system::dateTimeToString(const mrpt::system::TTimeStamp t)
Convert a timestamp into this textual form (UTC time): YEAR/MONTH/DAY,HH:MM:SS.MMM.
See also:
std::string mrpt::system::dateTimeLocalToString(const mrpt::system::TTimeStamp t)
Convert a timestamp into this textual form (in local time): YEAR/MONTH/DAY,HH:MM:SS.MMM.
See also:
std::string mrpt::system::dateToString(const mrpt::system::TTimeStamp t)
Convert a timestamp into this textual form: YEAR/MONTH/DAY.
double mrpt::system::extractDayTimeFromTimestamp(const mrpt::system::TTimeStamp t)
Returns the number of seconds ellapsed from midnight in the given timestamp.
std::string mrpt::system::timeToString(const mrpt::system::TTimeStamp t)
Convert a timestamp into this textual form (UTC): HH:MM:SS.MMMMMM.
std::string mrpt::system::timeLocalToString( const mrpt::system::TTimeStamp t, unsigned int secondFractionDigits = 6 )
Convert a timestamp into this textual form (in local time): HH:MM:SS.MMMMMM.
std::string mrpt::system::intervalFormat(const double seconds)
This function implements time interval formatting: Given a time in seconds, it will return a string describing the interval with the most appropriate unit.
E.g.:
“1 year, 3 days, 4 minutes”
“3 days, 8 hours”
“9 hours, 4 minutes, 4.3 sec”,
“3.34 sec”
“178.1 ms”
“87.1 us”
See also:
std::ostream& mrpt::system::operator << (std::ostream& o, const TTimeStamp& t)
Textual representation of a TTimeStamp as the plain number in time_since_epoch().count()
Macros
#define INVALID_TIMESTAMP
Represents an invalid timestamp, where applicable.
It returns a const reference to a thread_local static object of type mrpt::Clock::time_point initialized with the default constructor, which is used as the reference “invalid” timestamp.