Boost date_time

Gregorian

Date

Construction

Sytax	Description	Example
`date(greg_year, greg_month, greg_day)`	从日期的一部分构造，如果年、月或日超出范围，则抛出 `bad_year`, `bad_day_of_month`, `bad_day_month`	`date d(200, Jan, 10);`
`date(date d)`	拷贝构造函数	`date d1(d);`
`date(special_values sv)`	构造无限日期时间，非日期时间，最大最小日期时间	`date d1(neg_infin);` `date d2(pos_infin);` `date d3(not_a_date_time);` `date d4(max_date_time);` `date d5(min_date_time);`
`date()`	默认构造函数，初始化为 `not_a_date_time`，可以通过定义 `DATE_TIME_NO_DEFAULT_CONSTRUCTOR` 来禁用此构造函数	`date d; // d => not_a_date_time`

#include <iostream>
#include <boost/date_time/gregorian/gregorian.hpp>

using namespace boost::gregorian;

int main()
{
    // construction
    date d(2021, Mar, 14);
    std::cout << d << std::endl;  // 2021-Mar-14

    date d1(d);
    std::cout << d1 << std::endl;  // 2021-Mar-14

    date d_neg_inf(neg_infin);
    std::cout << d_neg_inf << std::endl;  // -infinity
    date d_pos_inf(pos_infin);
    std::cout << d_pos_inf << std::endl;  // +infinity
    date d_not_a_date(not_a_date_time);
    std::cout << d_not_a_date << std::endl;  // not-a-date-time
    date d_max(max_date_time);
    std::cout << d_max << std::endl;  // 9999-Dec-31
    date d_min(min_date_time);
    std::cout << d_min << std::endl;  // 1400-Jan-01

    date d_default;
    std::cout << d_default << std::endl;  // not-a-date-time
}

Construct from String

Sytax	Description	Example
`date from_string(std::string)`	从 `-` 或者 `/` 分隔符的字符串构造日期对象，顺序为年月日	`date d(from_string(std::string("2021-3-14")));`
`date from_undelimited_string(std::string)`	从 ISO 类型日期字符串构建日期对象，顺序为年月日	`date d(from_undelimited_string(std::string("20210314")));`

#include <iostream>
#include <boost/date_time/gregorian/gregorian.hpp>

using namespace boost::gregorian;

int main()
{
    // Construct from string
    std::string ds("2021/3/14");
    date dfs(from_string(ds));
    std::cout << dfs << std::endl;  // 2021-Mar-14

    std::string ds2("2021-3-14");
    date dfs2(from_string(ds2));
    std::cout << dfs2 << std::endl;  // 2021-Mar-14

    std::string ds_undel("20210314");
    date d_undel(from_undelimited_string(ds_undel));
    std::cout << d_undel << std::endl;  // 2021-Mar-14
}

Construct from Clock

Sytax	Description	Example
`day_clock::local_day()`	根据计算机的时区设置获取本地日期	`date d(day_clock::local_day());`
`day_clock::universal_day(`	获取 UTC 日期	`date d(day_clock::universal_day());`

#include <iostream>
#include <boost/date_time/gregorian/gregorian.hpp>

using namespace boost::gregorian;

int main()
{
    // construct from clock
    date d_local_clock(day_clock::local_day());
    std::cout << d_local_clock << std::endl;  // 2021-Mar-14

    date d_utc_clock(day_clock::universal_day());
    std::cout << d_utc_clock << std::endl;  // 2021-Mar-14

    date dddd(from_string(std::string("2021-3-14")));
    std::cout << dddd << std::endl;
}

Accessors

Sytax	Description	Example
`greg_year year() const`	获取日期的年份部分	`date d(2002,Jan,10); d.year(); // --> 2002`
`greg_month month() const`	获取日期的月份部分	`date d(2002,Jan,10); d.month(); // --> 1`
`greg_day day() const`	获取日期的日部分	`date d(2002,Jan,10); d.day(); // --> 10`
`greg_ymd year_month_day() const`	返回 `year_month_day` 结构体。当需要日期的所有3个部分时，效率更高	`date d(2002,Jan,10); date::ymd_type ymd = d.year_month_day(); // ymd.year --> 2002, ymd.month --> 1, ymd.day --> 10`
`greg_day_of_week day_of_week() const`	获取星期几	`date d(2002,Jan,10); d.day_of_week(); // --> Thursday`
`greg_day_of_year day_of_year() const`	获取一年中的哪一天。从 1 到 366	`date d(2000,Jan,10); d.day_of_year(); // --> 10`
`date end_of_month() const`	返回当前月的最后一天的日期对象	`date d(2000,Jan,10); d.end_of_month(); // --> 2000-Jan-31`
`bool is_infinity() const`	如果日期是正无穷大或负无穷大，则返回 true	`date d(pos_infin); d.is_infinity(); // --> true`
`bool is_neg_infinity() const`	如果日期为负无穷，则返回 true	`date d(neg_infin); d.is_neg_infinity(); // --> true`
`bool is_pos_infinity() const`	如果日期为正无穷大，则返回 true	`date d(pos_infin); d.is_pos_infinity(); // --> true`
`bool is_not_a_date() const`	如果值不是日期，则返回 true	`date d(not_a_date_time); d.is_not_a_date(); // --> true`
`bool is_special() const`	如果日期是任何 `special_value`，则返回 true	`date d(pos_infin); date d2(not_a_date_time); date d3(2005,Mar,1); d.is_special(); // --> true d2.is_special(); // --> true d3.is_special(); // --> false`
`long modjulian_day() const`	返回日期的修改后的儒略日
`long julian_day() const`	返回日期的儒略日
`int week_number() const`	返回日期的ISO 8601周编号
`date end_of_month() const`	返回日期的月份的最后一天	`date d(2000,Feb,1); //gets Feb 29 -- 2000 was leap year`, `date eom = d.end_of_month();`

#include <iostream>
#include <boost/date_time/gregorian/gregorian.hpp>
#include <vector>

using namespace boost::gregorian;

int main()
{
    // Accessors
    date today(day_clock::local_day());
    greg_year year = today.year();
    greg_month month = today.month();
    greg_day day = today.day();
    std::cout << "year: "<< year << ", month: " << month << ", day: " << day << std::endl;  // year: 2021, month: Mar, day: 14

    date::ymd_type ymd = today.year_month_day();
    std::cout << "year: "<< ymd.year << ", month: " << ymd.month << ", day: " << ymd.day << std::endl;  // year: 2021, month: Mar, day: 14

    date::day_of_week_type dow = today.day_of_week();
    std::cout << "day of week for today: " << dow << std::endl;  // day of week for today: Sun

    date::day_of_year_type doy = today.day_of_year();
    std::cout << "day of year for today: " << doy << std::endl;  // day of year for today: 73

    date eom = today.end_of_month();
    std::cout << "end of month for today: " << eom << std::endl;  // end of month for today: 2021-Mar-31

    std::cout << std::boolalpha;
    std::cout << "Is infinity for today: " << today.is_infinity() << std::endl;  // Is infinity for today: false
    std::cout << "Is neg infinity for today: " << today.is_neg_infinity() << std::endl;  // Is neg infinity for today: false
    std::cout << "Is pos infinity for today: " << today.is_pos_infinity() << std::endl;  // Is pos infinity for today: false
    std::cout << "Is not a date for today: " << today.is_not_a_date() << std::endl;  // Is not a date for today: false
    std::cout << "Is special for today: " << today.is_special() << std::endl;  // Is special for today: false

    std::vector<std::string> special_string = {"not_a_date_time",
                                            "neg_infin", "pos_infin",
                                            "min_date_time",  "max_date_time",
                                            "not_special", "NumSpecialValues"};
    std::cout << "As special for today: " << special_string[static_cast<int>(today.as_special())] << std::endl;  // As special for today: not_special

    std::cout << "modified julian day for today: " << today.modjulian_day() << std::endl;  // modified julian day for today: 59287
    std::cout << "julian day for today: " << today.julian_day() << std::endl;  // julian day for today: 2459288
    std::cout << "week number of today: " << today.week_number() << std::endl;  // week number of today: 10
    std::cout << "day number of today: " << today.day_number() << std::endl;  // day number of today: 2459288
}

Convert to String

Sytax	Description	Example
`std::string to_simple_string(date d)`	到 `YYYY-mmm-DD` 字符串，其中 `mmm` 是 3 个字符的月份名称	`"2002-Jan-01"`
`std::string to_iso_string(date d)`	到 `YYYYMMDD`，其中所有部分都是整数	`"20020131"`
`std::string to_iso_extended_string(date d)`	到 `YYYY-MM-DD`，其中所有部分均为整数	`"2002-01-31"`

#include <iostream>
#include <boost/date_time/gregorian/gregorian.hpp>

using namespace boost::gregorian;

int main()
{
    // convert to string
    std::string str_today = to_simple_string(today);
    std::cout << "to_simple_string: " << str_today << std::endl;  // to_simple_string: 2021-Mar-14
    std::string str_iso_today = to_iso_string(today);
    std::cout << "to_iso_string: " << str_iso_today << std::endl;  // to_iso_string: 20210314
    std::string str_iso_extend = to_iso_extended_string(today);
    std::cout << "to_iso_extended_string: " << str_iso_extend << std::endl;  // to_iso_extended_string: 2021-03-14
    std::wstring wstr_today = to_simple_wstring(today);
    std::wcout << "to_simple_wstring: "<< wstr_today << std::endl;  // to_simple_wstring: 2021-Mar-14
}

Operators

Sytax	Description
`operator<<`	流输出运算符
`operator>>`	流输入运算符
`operator==`, `operator!=`,`operator>`, `operator<`, `operator>=`, `operator<=`	比较运算符
`date operator+(date_duration) const`	返回日期加上日期偏移量
`date operator-(date_duration) const`	减去日期偏移量以返回日期
`date_duration operator-(date) const`	通过减去两个日期来返回 `date_duration`

#include <iostream>
#include <boost/date_time/gregorian/gregorian.hpp>

using namespace boost::gregorian;

int main()
{
    // operator
    std::stringstream ss("2021-Mar-14");
    date date_from_str;
    ss >> date_from_str;
    std::cout << date_from_str << std::endl;  // 2021-Mar-14

    date yesterday;
    date tomorrow;
    date_duration one_day(1);
    yesterday = today - one_day;
    tomorrow = today + one_day;
    std::cout << "yesterday: " << yesterday << std::endl;  // yesterday: 2021-Mar-13
    std::cout << "today: " << today << std::endl;  // today: 2021-Mar-14
    std::cout << "tomorrow:" << tomorrow << std::endl;  // tomorrow:2021-Mar-15

    std::cout << "yesterday == today? :" << (yesterday == today) << std::endl;  // yesterday == today? :false
    std::cout << "yesterday != today? :" << (yesterday != today) << std::endl;  // yesterday != today? :true
    std::cout << "yesterday > today? :" << (yesterday > today) << std::endl;  // yesterday > today? :false
    std::cout << "yesterday < today? :" << (yesterday < today) << std::endl;  // yesterday < today? :true
    std::cout << "yesterday >= today? :" << (yesterday >= today) << std::endl;  // yesterday >= today? :false
    std::cout << "yesterday <= today? :" << (yesterday <= today) << std::endl;  // yesterday <= today? :true
}

Struct tm Functions

Sytax	Description	Example
`tm to_tm(date)`	用于将日期对象转换为 `tm` 结构的函数。字段 `tm_hour`，`tm_min` 和 `tm_sec` 设置为零。`tm_isdst` 字段设置为 `-1`
`date date_from_tm(tm datetm)`	用于将 `tm` 结构转换为日期对象的函数。字段：`tm_wday`, `tm_yday`, `tm_hour`, `tm_min`, `tm_sec` 和 `tm_isdst` 被忽略

#include <iostream>
#include <boost/date_time/gregorian/gregorian.hpp>

using namespace boost::gregorian;

int main()
{
    // Struct tm Functions
    tm d_tm = to_tm(today);
    std::cout << "tm_year: " << d_tm.tm_year << std::endl;  // tm_year: 121
    std::cout << "tm_mon: " << d_tm.tm_mon << std::endl;  // tm_mon: 2
    std::cout << "tm_mday: " << d_tm.tm_mday << std::endl;  // tm_mday: 14
    std::cout << "tm_wday: " << d_tm.tm_wday << std::endl;  // tm_wday: 0
    std::cout << "tm_yday: " << d_tm.tm_yday << std::endl;  // tm_yday: 72
    std::cout << "tm_hour: " << d_tm.tm_hour << std::endl;  // tm_hour: 0
    std::cout << "tm_min: " << d_tm.tm_min << std::endl;  // tm_min: 0
    std::cout << "tm_sec: " << d_tm.tm_sec << std::endl;  // tm_sec: 0
    std::cout << "tm_isdst: " << d_tm.tm_isdst << std::endl;  // tm_isdst: -1

    d_tm.tm_hour = 12;
    d_tm.tm_min = 15;
    d_tm.tm_sec = 49;
    date d_from_tm = date_from_tm(d_tm);
    std::cout << d_from_tm << std::endl;  // 2021-Mar-14
}

Date Duration

date_duration 和 days 是一样的

typedef date_duration days;

Syntax	Description
`date_duration(long)`	Create a duration count
`days(special_values sv)`	Constructor for infinities, not-a-date-time, max_date_time, and min_date_time
`long days() const`	Get the day count
`bool is_negative() const`	True if number of days is less than zero
`static date_duration unit()`	Return smallest possible unit of duration type
`bool is_special() const`	Returns true if days is any `special_value`
`operator<<`, `operator>>`	Streaming operators
`operator==`, `operator!=`, `operator>`, `operator<`, `operator>=`, `operator<=`	A full complement of comparison operators
`date_duration operator+(date_duration) const`	Add date durations
`date_duration operator-(date_duration) const`	Subtract durations
`months(int num_of_months)`	A logical month representation
`years(int num_of_years)`	A logical representation of a year
`weeks(int num_of_weeks)`	A duration type representing a number of `n * 7` days

Date Period

Syntax	Description
`date_period(date, date)`	Create a period as [begin, end). If end is <= begin then the period will be invalid
`date_period(date, days)`	Create a period as [begin, begin+len) where end point would be begin+len. If len is <= zero then the period will be defined as invalid
`date_period(date_period)`	Copy constructor
`date_period shift(days)`	Add duration to both begin and end
`date_period expand(days)`	Subtract duration from begin and add duration to end
`date begin()`	Return first day of period
`date last()`	Return last date in the period
`date end()`	Return one past the last in period
`days length()`	Return the length of the date_period
`bool is_null()`	True if period is not well formed. eg: end less than or equal to begin
`bool contains(date)`	True if date is within the period. Zero length periods cannot contain any points
`bool contains(date_period)`	True if date period is within the period
`bool intersects(date_period)`	True if periods overlap
`date_period intersection(date_period)`	Calculate the intersection of 2 periods. Null if no intersection
`date_period is_adjacent(date_period)`	Check if two periods are adjacent, but not overlapping
`date_period is_after(date)`	Determine the period is after a given date.
`date_period is_before(date)`	Determine the period is before a given date
`date_period merge(date_period)`	Returns union of two periods. Null if no intersection
`date_period span(date_period)`	Combines two periods and any gap between them such that begin = min(p1.begin, p2.begin) and end = max(p1.end , p2.end)
`date_period shift(days)`	Add duration to both begin and end
`date_period expand(days)`	Subtract duration from begin and add duration to end
`std::string to_simple_string(date_period dp)`	To [YYYY-mmm-DD/YYYY-mmm-DD] string where mmm is 3 char month name
`operator<<`	ostream operator for date_period. Uses facet to format time points. Typical output: `[2002-Jan-01/2002-Jan-31]`.
`operator>>`	istream operator for date_period. Uses facet to parse time points
`operator==`, `operator!=`, `operator>`, `operator<`	A full complement of comparison operators
`operator<`	True if `dp1.end()` less than `dp2.begin()`
`operator>`	True if `dp1.begin()` greater than d`p2.end()`

Posix Time

Ptime

Syntax	Description
`ptime(date,time_duration)`	Construct from a date and offset
`ptime(ptime)`	Copy constructor
`ptime(special_values sv)`	Constructor for infinities, not-a-date-time, max_date_time, and min_date_time
`ptime`	Default constructor. Creates a ptime object initialized to not_a_date_time
`ptime time_from_string(std::string)`	From delimited string
`ptime from_iso_string(std::string)`	From non delimited iso form string
`ptime from_iso_extended_string(std::string)`	From delimited iso form string
`ptime second_clock::local_time()`	Get the local time, second level resolution, based on the time zone settings of the computer.
`ptime second_clock::universal_time()`	Get the UTC time
`ptime microsec_clock::local_time()`	Get the local time using a sub second resolution clock.
`ptime microsec_clock::universal_time()`	Get the UTC time using a sub second resolution clock
`ptime from_time_t(time_t t)`	Converts a time_t into a ptime
`ptime from_ftime<ptime>(FILETIME ft)`	Creates a ptime object from a FILETIME structure
`date date()`	Get the date part of a time
`time_duration time_of_day()`	Get the time offset in the day
`bool is_infinity() const`	Returns true if ptime is either positive or negative infinity
`bool is_neg_infinity() const`	Returns true if ptime is negative infinity
`bool is_pos_infinity() const`	Returns true if ptime is positive infinity
`bool is_not_a_date_time() const`	Returns true if value is not a ptime
`bool is_special() const`	Returns true if ptime is any special_value
`std::string to_simple_string(ptime)`	To `YYYY-mmm-DD HH:MM:SS.fffffffff` string where `mmm` 3 char month name. Fractional seconds only included if non-zero
`std::string to_iso_string(ptime)`	Convert to form `YYYYMMDDTHHMMSS,fffffffff` where `T` is the date-time separator
`std::string to_iso_extended_string(ptime)`	Convert to form `YYYY-MM-DDTHH:MM:SS,fffffffff` where `T` is the date-time separator
`operator<<`, `operator>>`	Streaming operators
`operator==`, `operator!=`, `operator>`, `operator<`, `operator>=`, `operator<=`	A full complement of comparison operators
`ptime operator+(days)`	Return a ptime adding a day offset
`ptime operator-(days)`	Return a ptime subtracting a day offset
`ptime operator+(time_duration)`	Return a ptime adding a time duration
`ptime operator-(time_duration)`	Return a ptime subtracting a time duration
`time_duration operator-(ptime)`	Take the difference between two times
`tm to_tm(ptime)`	A function for converting a `ptime` object to a `tm` struct. The `tm_isdst` field is set to `-1`
`ptime ptime_from_tm(tm timetm)`	A function for converting a `tm` struct to a `ptime` object. The fields: `tm_wday`, `tm_yday`, and `tm_isdst` are ignored
`tm to_tm(time_duration)`	A function for converting a `time_duration` object to a `tm` struct. The fields: `tm_year`, `tm_mon`, `tm_mday`, `tm_wday`, `tm_yday` are set to zero. The `tm_isdst` field is set to -1
`ptime from_time_t(std::time_t)`	Creates a `ptime` from the `time_t` parameter. The seconds held in the time_t are added to a time point of `1970-Jan-01`
`ptime from_ftime<ptime>(FILETIME)`	A template function that constructs a `ptime` from a FILETIME struct

Time Duration

Syntax	Description
`time_duration(hours, minutes, seconds, fractional_seconds)`	Construct a duration from the counts
`time_duration(special_value sv)`	Special values constructor
`hours(long)`	Number of hours
`minutes(long)`	Number of minutes
`seconds(long)`	Number of seconds
`milliseconds(long)`	Number of milliseconds
`microseconds(long)`	Number of microseconds
`nanoseconds(long)`	Number of nanoseconds
`time_duration duration_from_string(std::string)`	From delimited string
`boost::int64_t hours()`	Get the number of normalized hours (will give unpredictable results if calling `time_duration` is a `special_value`)
`boost::int64_t minutes()`	Get the number of minutes normalized `+/-(0..59)` (will give unpredictable results if calling `time_duration` is a `special_value`)
`boost::int64_t seconds() const`	Get the normalized number of second `+/-(0..59)` (will give unpredictable results if calling `time_duration` is a `special_value`)
`boost::int64_t total_seconds() const`	Get the total number of seconds truncating any fractional seconds (will give unpredictable results if calling `time_duration` is a `special_value`)
`boost::int64_t total_milliseconds() const`	Get the total number of milliseconds truncating any remaining digits (will give unpredictable results if calling `time_duration` is a `special_value`)
`oost::int64_t total_microseconds() const`	Get the total number of microseconds truncating any remaining digits (will give unpredictable results if calling `time_duration` is a `special_value`)
`boost::int64_t total_nanoseconds() const`	Get the total number of nanoseconds truncating any remaining digits (will give unpredictable results if calling `time_duration` is a `special_value`)
`boost::int64_t fractional_seconds() const`	Get the number of fractional seconds (will give unpredictable results if calling `time_duration` is a `special_value`)
`bool is_negative() const`	True if and only if duration is negative
`bool is_zero() const`	True if and only if duration is zero
`bool is_positive() const`	True if and only if duration is positive
`time_duration invert_sign() const`	Generate a new duration with the sign inverted
`time_duration abs() const`	Generate a new duration with the absolute value of the time duration
`date_time::time_resolutions time_duration::resolution()`	Describes the resolution capability of the `time_duration` class. `time_resolutions` is an enum of resolution possibilities ranging from seconds to nanoseconds
`unsigned short time_duration::num_fractional_digits()`	Returns the number of fractional digits the time resolution has
`boost::int64_t time_duration::ticks_per_second()`	Return the number of ticks in a second. For example, if the duration supports nanoseconds then the returned result will be `1,000,000,000 (1e+9)`
`boost::int64_t ticks()`	Return the raw count of the duration type (will give unpredictable results if calling `time_duration` is a `special_value`)
`time_duration time_duration::unit()`	Return smallest possible unit of duration type (1 nanosecond)
`bool is_neg_infinity() const`	Returns true if time_duration is negative infinity
`bool is_pos_infinity() const`	Returns true if time_duration is positive infinity
`bool is_not_a_date_time() const`	Returns true if value is not a time
`bool is_special() const`	Returns true if time_duration is any `special_value`
`std::string to_simple_string(time_duration)`	To `HH:MM:SS.fffffffff` were `fff` is fractional seconds that are only included if non-zero
`std::string to_iso_string(time_duration)`	Convert to form `HHMMSS,fffffffff`
`operator<<`, `operator>>`	Streaming operators
`operator==`, `operator!=`, `operator>`, `operator<`, `operator>=`, `operator<=`	A full complement of comparison operators
`time_duration operator+(time_duration)`	Add durations
`time_duration operator-(time_duration)`	Subtract durations
`time_duration operator/(int)`	Divide the length of a duration by an integer value. Discards any remainder
`time_duration operator*(int)`	Multiply the length of a duration by an integer value
`tm to_tm(time_duration)`	A function for converting a `time_duration` object to a `tm` struct. The fields: `tm_year`, `tm_mon`, `tm_mday`, `tm_wday`, `tm_yday` are set to zero. The `tm_isdst` field is set to -1

Time Period

Syntax	Description
`time_period(ptime, ptime)`	Create a period as `[begin, end)`. If end is <= begin then the period will be defined as invalid
`time_period(ptime, time_duration)`	Create a period as `[begin, begin+len)` where end would be `begin+len`. If len is <= zero then the period will be defined as invalid
`time_period(time_period rhs)`	Copy constructor
`time_period shift(time_duration)`	Add duration to both begin and end
`time_period expand(days)`	Subtract duration from begin and add duration to end
`ptime begin()`	Return first time of period
`ptime last()`	Return last time in the period
`ptime end()`	Return one past the last in period
`time_duration length()`	Return the length of the time period
`bool is_null()`	True if period is not well formed. eg: end is less than or equal to begin.
`bool contains(ptime)`	True if ptime is within the period. Zero length periods cannot contain any points
`bool contains(time_period)`	True if period is within the period
`bool intersects(time_period)`	True if periods overlap
`time_period intersection(time_period)`	Calculate the intersection of 2 periods. Null if no intersection
`time_period merge(time_period)`	Returns union of two periods. Null if no intersection
`time_period span(time_period)`	Combines two periods and any gap between them such that begin = min(p1.begin, p2.begin) and end = max(p1.end , p2.end)
`std::string to_simple_string(time_period dp)`	To `[YYYY-mmm-DD hh:mm:ss.fffffffff/YYYY-mmm-DD hh:mm:ss.fffffffff]` string where `mmm` is 3 char month name
`operator<<`	Output streaming operator for time duration
`operator>>`	Input streaming operator for time duration
`operator==`, `operator!=`	Equality operators. Periods are equal if `p1.begin == p2.begin && p1.last == p2.last`
`operator<`	Ordering with no overlap. True if `tp1.end()` less than `tp2.begin()`
`operator>`	Ordering with no overlap. True if `tp1.begin()` greater than `tp2.end()`
`operator<=`, `operator>=`	Defined in terms of the other operators

Time Iterators

Syntax	Description
`operator==(const ptime& rhs)`, `operator!=(const ptime& rhs)`, `operator>`, `operator<`, `operator>=`, `operator<=`	A full complement of comparison operators
`prefix increment`	Increment the iterator by the specified duration
`prefix decrement`	Decrement the iterator by the specified time duration

Local Time

Time Zone (abstract)

Syntax	Description
`string_type dst_zone_abbrev()`	Returns the daylight savings abbreviation for the represented time zone
`string_type std_zone_abbrev()`	Returns the standard abbreviation for the represented time zone
`string_type dst_zone_name()`	Returns the daylight savings name for the represented time zone
`string_type std_zone_name()`	Returns the standard name for the represented time zone
`bool has_dst()`	Returns true if this time zone does not make a daylight savings shift
`time_type dst_local_start_time(year_type)`	The date and time daylight savings time begins in given year
`time_type dst_local_end_time(year_type)`	The date and time daylight savings time ends in given year
`time_duration_type base_utc_offset()`	The amount of time offset from UTC (typically in hours)
`time_duration_type dst_offset()`	The amount of time shifted during daylight savings
`std::string to_posix_string()`	Returns a posix time zone string representation of this time_zone_base object

Posix Time Zone

Syntax	Description
`posix_time_zone(std::string)`	Construction
`std::string dst_zone_abbrev()`	Returns the daylight savings abbreviation for the represented time zone
`std::string std_zone_abbrev()`	Returns the standard abbreviation for the represented time zone
`std::string dst_zone_name()`	Returns the daylight savings ABBREVIATION for the represented time zone
`std::string std_zone_name()`	Returns the standard ABBREVIATION for the represented time zone
`bool has_dst()`	Returns true when time_zone’s shared_ptr to dst_calc_rules is not NULL
`ptime dst_local_start_time(greg_year)`	The date and time daylight savings time begins in given year. Returns not_a_date_time if this zone has no daylight savings
`ptime dst_local_end_time(greg_year)`	The date and time daylight savings time ends in given year. Returns not_a_date_time if this zone has no daylight savings
`time_duration base_utc_offset()`	The amount of time offset from UTC (typically in hours)
`posix_time::time_duration dst_offset()`	The amount of time shifted during daylight saving
`std::string to_posix_string()`	Returns a posix time zone string representation of this time_zone_base object

Time Zone Database

Syntax	Description
`tz_database()`	Constructor creates an empty database
`bool load_from_file(std::string)`	Parameter is path to a time zone spec csv file
`bool tz_db.add_record(std::string id, time_zone_ptr tz)`	Adds a time_zone, or a posix_time_zone, to the database. ID is the region name for this zone
`time_zone_ptr tz_db.time_zone_from_region(string id)`	Returns a time_zone, via a time_zone_ptr, that matches the region listed in the data file
`vector<string> tz_db.region_list()`	Returns a vector of strings that holds all the region ID strings from the database

Gregorian

Date

Construction

Construct from String

Construct from Clock

Accessors

Convert to String

Operators

Struct tm Functions

Date Duration

Date Period

Posix Time

Ptime

Time Duration

Time Period

Time Iterators

Local Time

Time Zone (abstract)

Posix Time Zone

Time Zone Database

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