Module `anise.time`¶

Classes¶

Class `Duration`¶

class Duration(
    string_repr
)

Defines generally usable durations for nanosecond precision valid for 32,768 centuries in either direction, and only on 80 bits / 10 octets.

Important conventions: 1. The negative durations can be mentally modeled "BC" years. One hours before 01 Jan 0000, it was "-1" years but 365 days and 23h into the current day. It was decided that the nanoseconds corresponds to the nanoseconds into the current century. In other words, a duration with centuries = -1 and nanoseconds = 0 is a greater duration (further from zero) than centuries = -1 and nanoseconds = 1. Duration zero minus one nanosecond returns a century of -1 and a nanosecond set to the number of nanoseconds in one century minus one. That difference is exactly 1 nanoseconds, where the former duration is "closer to zero" than the latter. As such, the largest negative duration that can be represented sets the centuries to i16::MAX and its nanoseconds to NANOSECONDS_PER_CENTURY. 2. It was also decided that opposite durations are equal, e.g. -15 minutes == 15 minutes. If the direction of time matters, use the signum function.

(Python documentation hints) :type string_repr: str :rtype: Duration

Methods¶

Method `EPSILON`¶

def EPSILON()

Method `MAX`¶

def MAX()

Method `MIN`¶

def MIN()

Method `MIN_NEGATIVE`¶

def MIN_NEGATIVE()

Method `MIN_POSITIVE`¶

def MIN_POSITIVE()

Method `ZERO`¶

def ZERO()

Method `abs`¶

def abs(
    self,
    /
)

Returns the absolute value of this duration :rtype: Duration

Method `approx`¶

def approx(
    self,
    /
)

Rounds this duration to the largest units represented in this duration.

This is useful to provide an approximate human duration. Under the hood, this function uses round, so the "tipping point" of the rounding is half way to the next increment of the greatest unit. As shown below, one example is that 35 hours and 59 minutes rounds to 1 day, but 36 hours and 1 minute rounds to 2 days because 2 days is closer to 36h 1 min than 36h 1 min is to 1 day.

Example¶

use hifitime::{Duration, TimeUnits};

assert_eq!((2.hours() + 3.minutes()).approx(), 2.hours());
assert_eq!((24.hours() + 3.minutes()).approx(), 1.days());
assert_eq!((35.hours() + 59.minutes()).approx(), 1.days());
assert_eq!((36.hours() + 1.minutes()).approx(), 2.days());
assert_eq!((47.hours() + 3.minutes()).approx(), 2.days());
assert_eq!((49.hours() + 3.minutes()).approx(), 2.days());

:rtype: Duration

Method `ceil`¶

def ceil(
    self,
    /,
    duration
)

Ceils this duration to the closest provided duration

This simply floors then adds the requested duration

Example¶

use hifitime::{Duration, TimeUnits};

let two_hours_three_min = 2.hours() + 3.minutes();
assert_eq!(two_hours_three_min.ceil(1.hours()), 3.hours());
assert_eq!(two_hours_three_min.ceil(30.minutes()), 2.hours() + 30.minutes());
assert_eq!(two_hours_three_min.ceil(4.hours()), 4.hours());
assert_eq!(two_hours_three_min.ceil(1.seconds()), two_hours_three_min + 1.seconds());
assert_eq!(two_hours_three_min.ceil(1.hours() + 5.minutes()), 2.hours() + 10.minutes());

:type duration: Duration :rtype: Duration

Method `decompose`¶

def decompose(
    self,
    /
)

Decomposes a Duration in its sign, days, hours, minutes, seconds, ms, us, ns

:rtype: typing.Tuple

Method `floor`¶

def floor(
    self,
    /,
    duration
)

Floors this duration to the closest duration from the bottom

Example¶

use hifitime::{Duration, TimeUnits};

let two_hours_three_min = 2.hours() + 3.minutes();
assert_eq!(two_hours_three_min.floor(1.hours()), 2.hours());
assert_eq!(two_hours_three_min.floor(30.minutes()), 2.hours());
// This is zero because we floor by a duration longer than the current duration, rounding it down
assert_eq!(two_hours_three_min.floor(4.hours()), 0.hours());
assert_eq!(two_hours_three_min.floor(1.seconds()), two_hours_three_min);
assert_eq!(two_hours_three_min.floor(1.hours() + 1.minutes()), 2.hours() + 2.minutes());
assert_eq!(two_hours_three_min.floor(1.hours() + 5.minutes()), 1.hours() + 5.minutes());

:type duration: Duration :rtype: Duration

Method `from_all_parts`¶

def from_all_parts(
    sign,
    days,
    hours,
    minutes,
    seconds,
    milliseconds,
    microseconds,
    nanoseconds
)

Creates a new duration from its parts :type sign: int :type days: int :type hours: int :type minutes: int :type seconds: int :type milliseconds: int :type microseconds: int :type nanoseconds: int :rtype: Duration

Method `from_parts`¶

def from_parts(
    centuries,
    nanoseconds
)

Create a normalized duration from its parts :type centuries: int :type nanoseconds: int :rtype: Duration

Method `from_total_nanoseconds`¶

def from_total_nanoseconds(
    nanos
)

Creates a new Duration from its full nanoseconds :type nanos: int :rtype: Duration

Method `is_negative`¶

def is_negative(
    self,
    /
)

Returns whether this is a negative or positive duration. :rtype: bool

Method `max`¶

def max(
    self,
    /,
    other
)

Returns the maximum of the two durations.

use hifitime::TimeUnits;

let d0 = 20.seconds();
let d1 = 21.seconds();

assert_eq!(d1, d1.max(d0));
assert_eq!(d1, d0.max(d1));

:type other: Duration :rtype: Duration

Method `min`¶

def min(
    self,
    /,
    other
)

Returns the minimum of the two durations.

use hifitime::TimeUnits;

let d0 = 20.seconds();
let d1 = 21.seconds();

assert_eq!(d0, d1.min(d0));
assert_eq!(d0, d0.min(d1));

:type other: Duration :rtype: Duration

Method `round`¶

def round(
    self,
    /,
    duration
)

Rounds this duration to the closest provided duration

This performs both a ceil and floor and returns the value which is the closest to current one.

Example¶

use hifitime::{Duration, TimeUnits};

let two_hours_three_min = 2.hours() + 3.minutes();
assert_eq!(two_hours_three_min.round(1.hours()), 2.hours());
assert_eq!(two_hours_three_min.round(30.minutes()), 2.hours());
assert_eq!(two_hours_three_min.round(4.hours()), 4.hours());
assert_eq!(two_hours_three_min.round(1.seconds()), two_hours_three_min);
assert_eq!(two_hours_three_min.round(1.hours() + 5.minutes()), 2.hours() + 10.minutes());

:type duration: Duration :rtype: Duration

Method `signum`¶

def signum(
    self,
    /
)

Returns the sign of this duration + 0 if the number is zero + 1 if the number is positive + -1 if the number is negative :rtype: int

Method `to_parts`¶

def to_parts(
    self,
    /
)

Returns the centuries and nanoseconds of this duration NOTE: These items are not public to prevent incorrect durations from being created by modifying the values of the structure directly. :rtype: typing.Tuple

Method `to_seconds`¶

def to_seconds(
    self,
    /
)

Returns this duration in seconds f64. For high fidelity comparisons, it is recommended to keep using the Duration structure. :rtype: float

Method `to_unit`¶

def to_unit(
    self,
    /,
    unit
)

:type unit: Unit :rtype: float

Method `total_nanoseconds`¶

def total_nanoseconds(
    self,
    /
)

Returns the total nanoseconds in a signed 128 bit integer :rtype: int

Class `DurationError`¶

class DurationError(
    *args,
    **kwargs
)

Class `Epoch`¶

class Epoch(
    string_repr
)

Defines a nanosecond-precision Epoch.

Refer to the appropriate functions for initializing this Epoch from different time scales or representations.

(Python documentation hints) :type string_repr: str :rtype: Epoch

Instance variables¶

Variable `duration`¶

:rtype: Duration

Variable `time_scale`¶

:rtype: TimeScale

Methods¶

Method `ceil`¶

def ceil(
    self,
    /,
    duration
)

Ceils this epoch to the closest provided duration in the TAI time scale

Example¶

use hifitime::{Epoch, TimeUnits};

let e = Epoch::from_gregorian_tai_hms(2022, 5, 20, 17, 57, 43);
assert_eq!(
    e.ceil(1.hours()),
    Epoch::from_gregorian_tai_hms(2022, 5, 20, 18, 0, 0)
);

// 45 minutes is a multiple of 3 minutes, hence this result
let e = Epoch::from_gregorian_tai(2022, 10, 3, 17, 44, 29, 898032665);
assert_eq!(
    e.ceil(3.minutes()),
    Epoch::from_gregorian_tai_hms(2022, 10, 3, 17, 45, 0)
);

:type duration: Duration :rtype: Epoch

Method `day_of_year`¶

def day_of_year(
    self,
    /
)

Returns the number of days since the start of the year. :rtype: float

Method `duration_in_year`¶

def duration_in_year(
    self,
    /
)

Returns the duration since the start of the year :rtype: Duration

Method `floor`¶

def floor(
    self,
    /,
    duration
)

Floors this epoch to the closest provided duration

Example¶

use hifitime::{Epoch, TimeUnits};

let e = Epoch::from_gregorian_tai_hms(2022, 5, 20, 17, 57, 43);
assert_eq!(
    e.floor(1.hours()),
    Epoch::from_gregorian_tai_hms(2022, 5, 20, 17, 0, 0)
);

let e = Epoch::from_gregorian_tai(2022, 10, 3, 17, 44, 29, 898032665);
assert_eq!(
    e.floor(3.minutes()),
    Epoch::from_gregorian_tai_hms(2022, 10, 3, 17, 42, 0)
);

:type duration: Duration :rtype: Epoch

Method `from_bdt_days`¶

def from_bdt_days(
    days
)

Initialize an Epoch from the number of days since the BeiDou Time Epoch, defined as January 1st 2006 (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS). :type days: float :rtype: Epoch

Method `from_bdt_nanoseconds`¶

def from_bdt_nanoseconds(
    nanoseconds
)

Initialize an Epoch from the number of days since the BeiDou Time Epoch, defined as January 1st 2006 (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS). This may be useful for time keeping devices that use BDT as a time source. :type nanoseconds: float :rtype: Epoch

Method `from_bdt_seconds`¶

def from_bdt_seconds(
    seconds
)

Initialize an Epoch from the number of seconds since the BeiDou Time Epoch, defined as January 1st 2006 (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS). :type seconds: float :rtype: Epoch

Method `from_et_duration`¶

def from_et_duration(
    duration_since_j2000
)

Initialize an Epoch from the Ephemeris Time duration past 2000 JAN 01 (J2000 reference) :type duration_since_j2000: Duration :rtype: Epoch

Method `from_et_seconds`¶

def from_et_seconds(
    seconds_since_j2000
)

Initialize an Epoch from the Ephemeris Time seconds past 2000 JAN 01 (J2000 reference) :type seconds_since_j2000: float :rtype: Epoch

Method `from_gpst_days`¶

def from_gpst_days(
    days
)

Initialize an Epoch from the number of days since the GPS Time Epoch, defined as UTC midnight of January 5th to 6th 1980 (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS#GPS_Time_.28GPST.29). :type days: float :rtype: Epoch

Method `from_gpst_nanoseconds`¶

def from_gpst_nanoseconds(
    nanoseconds
)

Initialize an Epoch from the number of nanoseconds since the GPS Time Epoch, defined as UTC midnight of January 5th to 6th 1980 (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS#GPS_Time_.28GPST.29). This may be useful for time keeping devices that use GPS as a time source. :type nanoseconds: float :rtype: Epoch

Method `from_gpst_seconds`¶

def from_gpst_seconds(
    seconds
)

Initialize an Epoch from the number of seconds since the GPS Time Epoch, defined as UTC midnight of January 5th to 6th 1980 (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS#GPS_Time_.28GPST.29). :type seconds: float :rtype: Epoch

Method `from_gregorian`¶

def from_gregorian(
    year,
    month,
    day,
    hour,
    minute,
    second,
    nanos,
    time_scale
)

Initialize from the Gregorian parts :type year: int :type month: int :type day: int :type hour: int :type minute: int :type second: int :type nanos: int :type time_scale: TimeScale :rtype: Epoch

Method `from_gregorian_at_midnight`¶

def from_gregorian_at_midnight(
    year,
    month,
    day,
    time_scale
)

Initialize from the Gregorian parts, time set to midnight :type year: int :type month: int :type day: int :type time_scale: TimeScale :rtype: Epoch

Method `from_gregorian_at_noon`¶

def from_gregorian_at_noon(
    year,
    month,
    day,
    time_scale
)

Initialize from the Gregorian parts, time set to noon :type year: int :type month: int :type day: int :type time_scale: TimeScale :rtype: Epoch

Method `from_gregorian_utc`¶

def from_gregorian_utc(
    year,
    month,
    day,
    hour,
    minute,
    second,
    nanos
)

Builds an Epoch from the provided Gregorian date and time in TAI. If invalid date is provided, this function will panic. Use maybe_from_gregorian_tai if unsure.

:type year: int :type month: int :type day: int :type hour: int :type minute: int :type second: int :type nanos: int :rtype: Epoch

Method `from_gst_days`¶

def from_gst_days(
    days
)

Initialize an Epoch from the number of days since the Galileo Time Epoch, starting on August 21st 1999 Midnight UT, (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS). :type days: float :rtype: Epoch

Method `from_gst_nanoseconds`¶

def from_gst_nanoseconds(
    nanoseconds
)

Initialize an Epoch from the number of nanoseconds since the Galileo Time Epoch, starting on August 21st 1999 Midnight UT, (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS). This may be useful for time keeping devices that use GST as a time source. :type nanoseconds: float :rtype: Epoch

Method `from_gst_seconds`¶

def from_gst_seconds(
    seconds
)

Initialize an Epoch from the number of seconds since the Galileo Time Epoch, starting on August 21st 1999 Midnight UT, (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS). :type seconds: float :rtype: Epoch

Method `from_jde_et`¶

def from_jde_et(
    days
)

Initialize from the JDE days :type days: float :rtype: Epoch

Method `from_jde_tai`¶

def from_jde_tai(
    days
)

Initialize an Epoch from given JDE in TAI time scale :type days: float :rtype: Epoch

Method `from_jde_tdb`¶

def from_jde_tdb(
    days
)

Initialize from Dynamic Barycentric Time (TDB) (same as SPICE ephemeris time) in JD days :type days: float :rtype: Epoch

Method `from_jde_utc`¶

def from_jde_utc(
    days
)

Initialize an Epoch from given JDE in UTC time scale :type days: float :rtype: Epoch

Method `from_mjd_tai`¶

def from_mjd_tai(
    days
)

Initialize an Epoch from given MJD in TAI time scale :type days: float :rtype: Epoch

Method `from_mjd_utc`¶

def from_mjd_utc(
    days
)

Initialize an Epoch from given MJD in UTC time scale :type days: float :rtype: Epoch

Method `from_ptp_duration`¶

def from_ptp_duration(
    duration
)

Initialize an Epoch from the provided IEEE 1588-2008 (PTPv2) duration since TAI midnight 1970 January 01. PTP uses the TAI timescale but with the Unix Epoch for compatibility with unix systems.

:type duration: Duration :rtype: Epoch

Method `from_ptp_nanoseconds`¶

def from_ptp_nanoseconds(
    nanoseconds
)

Initialize an Epoch from the provided IEEE 1588-2008 (PTPv2) nanoseconds timestamp since TAI midnight 1970 January 01. PTP uses the TAI timescale but with the Unix Epoch for compatibility with unix systems.

:type nanoseconds: int :rtype: Epoch

Method `from_ptp_seconds`¶

def from_ptp_seconds(
    seconds
)

Initialize an Epoch from the provided IEEE 1588-2008 (PTPv2) second timestamp since TAI midnight 1970 January 01. PTP uses the TAI timescale but with the Unix Epoch for compatibility with unix systems.

:type seconds: float :rtype: Epoch

Method `from_qzsst_days`¶

def from_qzsst_days(
    days
)

Initialize an Epoch from the number of days since the QZSS Time Epoch, defined as UTC midnight of January 5th to 6th 1980 (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS#GPS_Time_.28GPST.29). :type days: float :rtype: Epoch

Method `from_qzsst_nanoseconds`¶

def from_qzsst_nanoseconds(
    nanoseconds
)

Initialize an Epoch from the number of nanoseconds since the QZSS Time Epoch, defined as UTC midnight of January 5th to 6th 1980 (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS#GPS_Time_.28GPST.29). This may be useful for time keeping devices that use QZSS as a time source. :type nanoseconds: int :rtype: Epoch

Method `from_qzsst_seconds`¶

def from_qzsst_seconds(
    seconds
)

Initialize an Epoch from the number of seconds since the QZSS Time Epoch, defined as UTC midnight of January 5th to 6th 1980 (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS#GPS_Time_.28GPST.29). :type seconds: float :rtype: Epoch

Method `from_tai_days`¶

def from_tai_days(
    days
)

Initialize an Epoch from the provided TAI days since 1900 January 01 at midnight :type days: float :rtype: Epoch

Method `from_tai_duration`¶

def from_tai_duration(
    duration
)

Creates a new Epoch from a Duration as the time difference between this epoch and TAI reference epoch. :type duration: Duration :rtype: Epoch

Method `from_tai_parts`¶

def from_tai_parts(
    centuries,
    nanoseconds
)

Creates a new Epoch from its centuries and nanosecond since the TAI reference epoch. :type centuries: int :type nanoseconds: int :rtype: Epoch

Method `from_tai_seconds`¶

def from_tai_seconds(
    seconds
)

Initialize an Epoch from the provided TAI seconds since 1900 January 01 at midnight :type seconds: float :rtype: Epoch

Method `from_tdb_duration`¶

def from_tdb_duration(
    duration_since_j2000
)

Initialize from Dynamic Barycentric Time (TDB) (same as SPICE ephemeris time) whose epoch is 2000 JAN 01 noon TAI. :type duration_since_j2000: Duration :rtype: Epoch

Method `from_tdb_seconds`¶

def from_tdb_seconds(
    seconds_j2000
)

Initialize an Epoch from Dynamic Barycentric Time (TDB) seconds past 2000 JAN 01 midnight (difference than SPICE) NOTE: This uses the ESA algorithm, which is a notch more complicated than the SPICE algorithm, but more precise. In fact, SPICE algorithm is precise +/- 30 microseconds for a century whereas ESA algorithm should be exactly correct. :type seconds_j2000: float :rtype: Epoch

Method `from_tt_duration`¶

def from_tt_duration(
    duration
)

Initialize an Epoch from the provided TT seconds (approximated to 32.184s delta from TAI) :type duration: Duration :rtype: Epoch

Method `from_tt_seconds`¶

def from_tt_seconds(
    seconds
)

Initialize an Epoch from the provided TT seconds (approximated to 32.184s delta from TAI) :type seconds: float :rtype: Epoch

Method `from_unix_milliseconds`¶

def from_unix_milliseconds(
    milliseconds
)

Initialize an Epoch from the provided UNIX millisecond timestamp since UTC midnight 1970 January 01. :type milliseconds: float :rtype: Epoch

Method `from_unix_seconds`¶

def from_unix_seconds(
    seconds
)

Initialize an Epoch from the provided UNIX second timestamp since UTC midnight 1970 January 01. :type seconds: float :rtype: Epoch

Method `from_utc_days`¶

def from_utc_days(
    days
)

Initialize an Epoch from the provided UTC days since 1900 January 01 at midnight :type days: float :rtype: Epoch

Method `from_utc_seconds`¶

def from_utc_seconds(
    seconds
)

Initialize an Epoch from the provided UTC seconds since 1900 January 01 at midnight :type seconds: float :rtype: Epoch

Method `fromdatetime`¶

def fromdatetime(
    dt
)

Builds an Epoch in UTC from the provided datetime after timezone correction if any is present. :type dt: datetime.datetime :rtype: Epoch

Method `hours`¶

def hours(
    self,
    /
)

Returns the hours of the Gregorian representation of this epoch in the time scale it was initialized in. :rtype: int

Method `init_from_bdt_days`¶

def init_from_bdt_days(
    days
)

WARNING: Deprecated since 4.1.1; Use from_bdt_days instead Initialize an Epoch from the number of days since the BeiDou Time Epoch, defined as January 1st 2006 (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS). :type days: float :rtype: Epoch

Method `init_from_bdt_nanoseconds`¶

def init_from_bdt_nanoseconds(
    nanoseconds
)

WARNING: Deprecated since 4.1.1; Use from_bdt_nanoseconds instead Initialize an Epoch from the number of days since the BeiDou Time Epoch, defined as January 1st 2006 (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS). This may be useful for time keeping devices that use BDT as a time source. :type nanoseconds: float :rtype: Epoch

Method `init_from_bdt_seconds`¶

def init_from_bdt_seconds(
    seconds
)

WARNING: Deprecated since 4.1.1; Use from_bdt_seconds instead Initialize an Epoch from the number of seconds since the BeiDou Time Epoch, defined as January 1st 2006 (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS). :type seconds: float :rtype: Epoch

Method `init_from_et_duration`¶

def init_from_et_duration(
    duration_since_j2000
)

WARNING: Deprecated since 4.1.1; Use from_et_duration instead Initialize an Epoch from the Ephemeris Time duration past 2000 JAN 01 (J2000 reference) :type duration_since_j2000: Duration :rtype: Epoch

Method `init_from_et_seconds`¶

def init_from_et_seconds(
    seconds_since_j2000
)

WARNING: Deprecated since 4.1.1; Use from_et_seconds instead Initialize an Epoch from the Ephemeris Time seconds past 2000 JAN 01 (J2000 reference) :type seconds_since_j2000: float :rtype: Epoch

Method `init_from_gpst_days`¶

def init_from_gpst_days(
    days
)

WARNING: Deprecated since 4.1.1; Use from_gpst_days instead Initialize an Epoch from the number of days since the GPS Time Epoch, defined as UTC midnight of January 5th to 6th 1980 (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS#GPS_Time_.28GPST.29). :type days: float :rtype: Epoch

Method `init_from_gpst_nanoseconds`¶

def init_from_gpst_nanoseconds(
    nanoseconds
)

WARNING: Deprecated since 4.1.1; Use from_gpst_nanoseconds instead Initialize an Epoch from the number of nanoseconds since the GPS Time Epoch, defined as UTC midnight of January 5th to 6th 1980 (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS#GPS_Time_.28GPST.29). This may be useful for time keeping devices that use GPS as a time source. :type nanoseconds: float :rtype: Epoch

Method `init_from_gpst_seconds`¶

def init_from_gpst_seconds(
    seconds
)

WARNING: Deprecated since 4.1.1; Use from_gpst_seconds instead Initialize an Epoch from the number of seconds since the GPS Time Epoch, defined as UTC midnight of January 5th to 6th 1980 (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS#GPS_Time_.28GPST.29). :type seconds: float :rtype: Epoch

Method `init_from_gregorian`¶

def init_from_gregorian(
    year,
    month,
    day,
    hour,
    minute,
    second,
    nanos,
    time_scale
)

WARNING: Deprecated since 4.1.1; Use from_gregorian instead Initialize from the Gregorian parts :type year: int :type month: int :type day: int :type hour: int :type minute: int :type second: int :type nanos: int :type time_scale: TimeScale :rtype: Epoch

Method `init_from_gregorian_at_midnight`¶

def init_from_gregorian_at_midnight(
    year,
    month,
    day,
    time_scale
)

WARNING: Deprecated since 4.1.1; Use from_gregorian_at_midnight instead Initialize from the Gregorian parts, time set to midnight :type year: int :type month: int :type day: int :type time_scale: TimeScale :rtype: Epoch

Method `init_from_gregorian_at_noon`¶

def init_from_gregorian_at_noon(
    year,
    month,
    day,
    time_scale
)

WARNING: Deprecated since 4.1.1; Use from_gregorian_at_noon instead Initialize from the Gregorian parts, time set to noon :type year: int :type month: int :type day: int :type time_scale: TimeScale :rtype: Epoch

Method `init_from_gregorian_utc`¶

def init_from_gregorian_utc(
    year,
    month,
    day,
    hour,
    minute,
    second,
    nanos
)

WARNING: Deprecated since 4.1.1; Use from_gregorian_utc instead Builds an Epoch from the provided Gregorian date and time in TAI. If invalid date is provided, this function will panic. Use maybe_from_gregorian_tai if unsure.

:type year: int :type month: int :type day: int :type hour: int :type minute: int :type second: int :type nanos: int :rtype: Epoch

Method `init_from_gst_days`¶

def init_from_gst_days(
    days
)

WARNING: Deprecated since 4.1.1; Use from_gst_days instead Initialize an Epoch from the number of days since the Galileo Time Epoch, starting on August 21st 1999 Midnight UT, (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS). :type days: float :rtype: Epoch

Method `init_from_gst_nanoseconds`¶

def init_from_gst_nanoseconds(
    nanoseconds
)

WARNING: Deprecated since 4.1.1; Use from_gst_nanoseconds instead Initialize an Epoch from the number of nanoseconds since the Galileo Time Epoch, starting on August 21st 1999 Midnight UT, (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS). This may be useful for time keeping devices that use GST as a time source. :type nanoseconds: float :rtype: Epoch

Method `init_from_gst_seconds`¶

def init_from_gst_seconds(
    seconds
)

WARNING: Deprecated since 4.1.1; Use from_gst_seconds instead Initialize an Epoch from the number of seconds since the Galileo Time Epoch, starting on August 21st 1999 Midnight UT, (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS). :type seconds: float :rtype: Epoch

Method `init_from_jde_et`¶

def init_from_jde_et(
    days
)

WARNING: Deprecated since 4.1.1; Use from_jde_et instead Initialize from the JDE days :type days: float :rtype: Epoch

Method `init_from_jde_tai`¶

def init_from_jde_tai(
    days
)

WARNING: Deprecated since 4.1.1; Use from_jde_tai instead Initialize an Epoch from given JDE in TAI time scale :type days: float :rtype: Epoch

Method `init_from_jde_tdb`¶

def init_from_jde_tdb(
    days
)

WARNING: Deprecated since 4.1.1; Use from_jde_tdb instead Initialize from Dynamic Barycentric Time (TDB) (same as SPICE ephemeris time) in JD days :type days: float :rtype: Epoch

Method `init_from_jde_utc`¶

def init_from_jde_utc(
    days
)

WARNING: Deprecated since 4.1.1; Use from_jde_utc instead Initialize an Epoch from given JDE in UTC time scale :type days: float :rtype: Epoch

Method `init_from_mjd_tai`¶

def init_from_mjd_tai(
    days
)

WARNING: Deprecated since 4.1.1; Use from_mjd_tai instead Initialize an Epoch from given MJD in TAI time scale :type days: float :rtype: Epoch

Method `init_from_mjd_utc`¶

def init_from_mjd_utc(
    days
)

WARNING: Deprecated since 4.1.1; Use from_mjd_utc instead Initialize an Epoch from given MJD in UTC time scale :type days: float :rtype: Epoch

Method `init_from_qzsst_days`¶

def init_from_qzsst_days(
    days
)

WARNING: Deprecated since 4.1.1; Use from_qzsst_days instead Initialize an Epoch from the number of days since the QZSS Time Epoch, defined as UTC midnight of January 5th to 6th 1980 (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS#GPS_Time_.28GPST.29). :type days: float :rtype: Epoch

Method `init_from_qzsst_nanoseconds`¶

def init_from_qzsst_nanoseconds(
    nanoseconds
)

WARNING: Deprecated since 4.1.1; Use from_qzsst_nanoseconds instead Initialize an Epoch from the number of nanoseconds since the QZSS Time Epoch, defined as UTC midnight of January 5th to 6th 1980 (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS#GPS_Time_.28GPST.29). This may be useful for time keeping devices that use QZSS as a time source. :type nanoseconds: int :rtype: Epoch

Method `init_from_qzsst_seconds`¶

def init_from_qzsst_seconds(
    seconds
)

WARNING: Deprecated since 4.1.1; Use from_qzsst_seconds instead Initialize an Epoch from the number of seconds since the QZSS Time Epoch, defined as UTC midnight of January 5th to 6th 1980 (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS#GPS_Time_.28GPST.29). :type seconds: float :rtype: Epoch

Method `init_from_tai_days`¶

def init_from_tai_days(
    days
)

WARNING: Deprecated since 4.1.1; Use from_tai_days instead Initialize an Epoch from the provided TAI days since 1900 January 01 at midnight :type days: float :rtype: Epoch

Method `init_from_tai_duration`¶

def init_from_tai_duration(
    duration
)

WARNING: Deprecated since 4.1.1; Use from_tai_duration instead Creates a new Epoch from a Duration as the time difference between this epoch and TAI reference epoch. :type duration: Duration :rtype: Epoch

Method `init_from_tai_parts`¶

def init_from_tai_parts(
    centuries,
    nanoseconds
)

WARNING: Deprecated since 4.1.1; Use from_tai_parts instead Creates a new Epoch from its centuries and nanosecond since the TAI reference epoch. :type centuries: int :type nanoseconds: int :rtype: Epoch

Method `init_from_tai_seconds`¶

def init_from_tai_seconds(
    seconds
)

WARNING: Deprecated since 4.1.1; Use from_tai_seconds instead Initialize an Epoch from the provided TAI seconds since 1900 January 01 at midnight :type seconds: float :rtype: Epoch

Method `init_from_tdb_duration`¶

def init_from_tdb_duration(
    duration_since_j2000
)

WARNING: Deprecated since 4.1.1; Use from_tdb_duration instead Initialize from Dynamic Barycentric Time (TDB) (same as SPICE ephemeris time) whose epoch is 2000 JAN 01 noon TAI. :type duration_since_j2000: Duration :rtype: Epoch

Method `init_from_tdb_seconds`¶

def init_from_tdb_seconds(
    seconds_j2000
)

WARNING: Deprecated since 4.1.1; Use from_tdb_seconds instead Initialize an Epoch from Dynamic Barycentric Time (TDB) seconds past 2000 JAN 01 midnight (difference than SPICE) NOTE: This uses the ESA algorithm, which is a notch more complicated than the SPICE algorithm, but more precise. In fact, SPICE algorithm is precise +/- 30 microseconds for a century whereas ESA algorithm should be exactly correct. :type seconds_j2000: float :rtype: Epoch

Method `init_from_tt_duration`¶

def init_from_tt_duration(
    duration
)

WARNING: Deprecated since 4.1.1; Use from_tt_duration instead Initialize an Epoch from the provided TT seconds (approximated to 32.184s delta from TAI) :type duration: Duration :rtype: Epoch

Method `init_from_tt_seconds`¶

def init_from_tt_seconds(
    seconds
)

WARNING: Deprecated since 4.1.1; Use from_tt_seconds instead Initialize an Epoch from the provided TT seconds (approximated to 32.184s delta from TAI) :type seconds: float :rtype: Epoch

Method `init_from_unix_milliseconds`¶

def init_from_unix_milliseconds(
    milliseconds
)

WARNING: Deprecated since 4.1.1; Use from_unix_milliseconds instead Initialize an Epoch from the provided UNIX millisecond timestamp since UTC midnight 1970 January 01. :type milliseconds: float :rtype: Epoch

Method `init_from_unix_seconds`¶

def init_from_unix_seconds(
    seconds
)

WARNING: Deprecated since 4.1.1; Use from_unix_seconds instead Initialize an Epoch from the provided UNIX second timestamp since UTC midnight 1970 January 01. :type seconds: float :rtype: Epoch

Method `init_from_utc_days`¶

def init_from_utc_days(
    days
)

WARNING: Deprecated since 4.1.1; Use from_utc_days instead Initialize an Epoch from the provided UTC days since 1900 January 01 at midnight :type days: float :rtype: Epoch

Method `init_from_utc_seconds`¶

def init_from_utc_seconds(
    seconds
)

WARNING: Deprecated since 4.1.1; Use from_utc_seconds instead Initialize an Epoch from the provided UTC seconds since 1900 January 01 at midnight :type seconds: float :rtype: Epoch

Method `isoformat`¶

def isoformat(
    self,
    /
)

Equivalent to datetime.isoformat, and truncated to 23 chars, refer to https://docs.rs/hifitime/latest/hifitime/efmt/format/struct.Format.html for format options :rtype: str

Method `leap_seconds`¶

def leap_seconds(
    self,
    /,
    iers_only
)

Get the accumulated number of leap seconds up to this Epoch accounting only for the IERS leap seconds and the SOFA scaling from 1960 to 1972, depending on flag. Returns None if the epoch is before 1960, year at which UTC was defined.

Why does this function return an `Option` when the other returns a value¶

This is to match the iauDat function of SOFA (src/dat.c). That function will return a warning and give up if the start date is before 1960. :type iers_only: bool :rtype: float

Method `leap_seconds_iers`¶

def leap_seconds_iers(
    self,
    /
)

Get the accumulated number of leap seconds up to this Epoch accounting only for the IERS leap seconds. :rtype: int

Method `leap_seconds_with_file`¶

def leap_seconds_with_file(
    self,
    /,
    iers_only,
    provider
)

Get the accumulated number of leap seconds up to this Epoch from the provided LeapSecondProvider. Returns None if the epoch is before 1960, year at which UTC was defined.

Why does this function return an `Option` when the other returns a value¶

This is to match the iauDat function of SOFA (src/dat.c). That function will return a warning and give up if the start date is before 1960.

:type iers_only: bool :type provider: LeapSecondsFile :rtype: float

Method `max`¶

def max(
    self,
    /,
    other
)

Returns the maximum of the two epochs.

use hifitime::Epoch;

let e0 = Epoch::from_gregorian_utc_at_midnight(2022, 10, 20);
let e1 = Epoch::from_gregorian_utc_at_midnight(2022, 10, 21);

assert_eq!(e1, e1.max(e0));
assert_eq!(e1, e0.max(e1));

Note: this uses a pointer to self which will be copied immediately because Python requires a pointer. :type other: Epoch :rtype: Epoch

Method `microseconds`¶

def microseconds(
    self,
    /
)

Returns the microseconds of the Gregorian representation of this epoch in the time scale it was initialized in. :rtype: int

Method `milliseconds`¶

def milliseconds(
    self,
    /
)

Returns the milliseconds of the Gregorian representation of this epoch in the time scale it was initialized in. :rtype: int

Method `min`¶

def min(
    self,
    /,
    other
)

Returns the minimum of the two epochs.

use hifitime::Epoch;

let e0 = Epoch::from_gregorian_utc_at_midnight(2022, 10, 20);
let e1 = Epoch::from_gregorian_utc_at_midnight(2022, 10, 21);

assert_eq!(e0, e1.min(e0));
assert_eq!(e0, e0.min(e1));

Note: this uses a pointer to self which will be copied immediately because Python requires a pointer. :type other: Epoch :rtype: Epoch

Method `minutes`¶

def minutes(
    self,
    /
)

Returns the minutes of the Gregorian representation of this epoch in the time scale it was initialized in. :rtype: int

Method `month_name`¶

def month_name(
    self,
    /
)

:rtype: MonthName

Method `nanoseconds`¶

def nanoseconds(
    self,
    /
)

Returns the nanoseconds of the Gregorian representation of this epoch in the time scale it was initialized in. :rtype: int

Method `next`¶

def next(
    self,
    /,
    weekday
)

Returns the next weekday.

use hifitime::prelude::*;

let epoch = Epoch::from_gregorian_utc_at_midnight(1988, 1, 2);
assert_eq!(epoch.weekday_utc(), Weekday::Saturday);
assert_eq!(epoch.next(Weekday::Sunday), Epoch::from_gregorian_utc_at_midnight(1988, 1, 3));
assert_eq!(epoch.next(Weekday::Monday), Epoch::from_gregorian_utc_at_midnight(1988, 1, 4));
assert_eq!(epoch.next(Weekday::Tuesday), Epoch::from_gregorian_utc_at_midnight(1988, 1, 5));
assert_eq!(epoch.next(Weekday::Wednesday), Epoch::from_gregorian_utc_at_midnight(1988, 1, 6));
assert_eq!(epoch.next(Weekday::Thursday), Epoch::from_gregorian_utc_at_midnight(1988, 1, 7));
assert_eq!(epoch.next(Weekday::Friday), Epoch::from_gregorian_utc_at_midnight(1988, 1, 8));
assert_eq!(epoch.next(Weekday::Saturday), Epoch::from_gregorian_utc_at_midnight(1988, 1, 9));

:type weekday: Weekday :rtype: Epoch

Method `next_weekday_at_midnight`¶

def next_weekday_at_midnight(
    self,
    /,
    weekday
)

:type weekday: Weekday :rtype: Epoch

Method `next_weekday_at_noon`¶

def next_weekday_at_noon(
    self,
    /,
    weekday
)

:type weekday: Weekday :rtype: Epoch

Method `precise_timescale_conversion`¶

def precise_timescale_conversion(
    self,
    /,
    forward,
    reference_epoch,
    polynomial,
    target
)

Converts this [Epoch] into targeted [TimeScale] using provided [Polynomial].

Input¶

forward: whether this is forward or backward conversion. For example, using GPST-UTC [Polynomial]
GPST->UTC is the forward conversion
UTC->GPST is the backward conversion
reference_epoch: any reference [Epoch] for the provided [Polynomial].

While we support any time difference, it should remain short in pratice (a day at most, for precise applications). - polynomial: that must be valid for this reference [Epoch], used in the equation a0 + a1*dt + a2*dt² = GPST-UTC for example. - target: targetted [TimeScale] we will transition to.

Example:

use hifitime::{Epoch, TimeScale, Polynomial, Unit};

// random GPST Epoch for forward conversion to UTC
let t_gpst = Epoch::from_gregorian(2020, 01, 01, 0, 0, 0, 0, TimeScale::GPST);

// Let's say we know the GPST-UTC polynomials for that day,
// They allow precise forward transition from GPST to UTC,
// and precise backward transition from UTC to GPST.
let gpst_utc_polynomials = Polynomial::from_constant_offset_nanoseconds(1.0);

// This is the reference [Epoch] attached to the publication of these polynomials.
// You should use polynomials that remain valid and were provided recently (usually one day at most).
// Example: polynomials were published 1 hour ago.
let gpst_reference = t_gpst - 1.0 * Unit::Hour;

// Forward conversion (to UTC) GPST - a0 + a1 *dt + a2*dt² = UTC
let t_utc = t_gpst.precise_timescale_conversion(true, gpst_reference, gpst_utc_polynomials, TimeScale::UTC)
    .unwrap();

// Verify we did transition to UTC
assert_eq!(t_utc.time_scale, TimeScale::UTC);

// Verify the resulting [Epoch] is the coarse GPST->UTC transition + fine correction
let reversed = t_utc.to_time_scale(TimeScale::GPST) + 1.0 * Unit::Nanosecond;
assert_eq!(reversed, t_gpst);

// Apply the backward transition, from t_utc back to t_gpst.
// The timescale conversion works both ways: (from UTC) GPST = UTC + a0 + a1 *dt + a2*dt²
let backwards = t_utc.precise_timescale_conversion(false, gpst_reference, gpst_utc_polynomials, TimeScale::GPST)
    .unwrap();

assert_eq!(backwards, t_gpst);

// It is important to understand that your reference point does not have to be in the past.
// The only logic that should prevail is to always minimize interpolation gap.
// In other words, if you can access future interpolation information that would minimize the data gap, they should prevail.
// Example: +30' in the future.
let gpst_reference = t_gpst + 30.0 * Unit::Minute;

// Forward conversion (to UTC) but using polynomials that were released 1 hour after t_gpst
let t_utc = t_gpst.precise_timescale_conversion(true, gpst_reference, gpst_utc_polynomials, TimeScale::UTC)
    .unwrap();

// Verifications
assert_eq!(t_utc.time_scale, TimeScale::UTC);

let reversed = t_utc.to_time_scale(TimeScale::GPST) + 1.0 * Unit::Nanosecond;
assert_eq!(reversed, t_gpst);

:type forward: bool :type reference_epoch: Epoch :type polynomial: Polynomial :type target: TimeScale :rtype: Epoch

Method `previous`¶

def previous(
    self,
    /,
    weekday
)

Returns the next weekday.

use hifitime::prelude::*;

let epoch = Epoch::from_gregorian_utc_at_midnight(1988, 1, 2);
assert_eq!(epoch.previous(Weekday::Friday), Epoch::from_gregorian_utc_at_midnight(1988, 1, 1));
assert_eq!(epoch.previous(Weekday::Thursday), Epoch::from_gregorian_utc_at_midnight(1987, 12, 31));
assert_eq!(epoch.previous(Weekday::Wednesday), Epoch::from_gregorian_utc_at_midnight(1987, 12, 30));
assert_eq!(epoch.previous(Weekday::Tuesday), Epoch::from_gregorian_utc_at_midnight(1987, 12, 29));
assert_eq!(epoch.previous(Weekday::Monday), Epoch::from_gregorian_utc_at_midnight(1987, 12, 28));
assert_eq!(epoch.previous(Weekday::Sunday), Epoch::from_gregorian_utc_at_midnight(1987, 12, 27));
assert_eq!(epoch.previous(Weekday::Saturday), Epoch::from_gregorian_utc_at_midnight(1987, 12, 26));

:type weekday: Weekday :rtype: Epoch

Method `previous_weekday_at_midnight`¶

def previous_weekday_at_midnight(
    self,
    /,
    weekday
)

:type weekday: Weekday :rtype: Epoch

Method `previous_weekday_at_noon`¶

def previous_weekday_at_noon(
    self,
    /,
    weekday
)

:type weekday: Weekday :rtype: Epoch

Method `round`¶

def round(
    self,
    /,
    duration
)

Rounds this epoch to the closest provided duration in TAI

Example¶

use hifitime::{Epoch, TimeUnits};

let e = Epoch::from_gregorian_tai_hms(2022, 5, 20, 17, 57, 43);
assert_eq!(
    e.round(1.hours()),
    Epoch::from_gregorian_tai_hms(2022, 5, 20, 18, 0, 0)
);

:type duration: Duration :rtype: Epoch

Method `seconds`¶

def seconds(
    self,
    /
)

Returns the seconds of the Gregorian representation of this epoch in the time scale it was initialized in. :rtype: int

Method `strftime`¶

def strftime(
    self,
    /,
    format_str
)

Formats the epoch according to the given format string. Supports a subset of C89 and hifitime-specific format codes. Refer to https://docs.rs/hifitime/latest/hifitime/efmt/format/struct.Format.html for available format options. :type format_str: str :rtype: str

Method `strptime`¶

def strptime(
    epoch_str,
    format_str
)

Equivalent to datetime.strptime, refer to https://docs.rs/hifitime/latest/hifitime/efmt/format/struct.Format.html for format options :type epoch_str: str :type format_str: str :rtype: Epoch

Method `system_now`¶

def system_now()

Returns the computer clock in UTC

:rtype: Epoch

Method `timedelta`¶

def timedelta(
    self,
    /,
    other
)

Differences between two epochs :type other: Duration :rtype: Duration

Method `to_bdt_days`¶

def to_bdt_days(
    self,
    /
)

Returns days past BDT (BeiDou) Time Epoch, defined as Jan 01 2006 UTC (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS). :rtype: float

Method `to_bdt_duration`¶

def to_bdt_duration(
    self,
    /
)

Returns Duration past BDT (BeiDou) time Epoch. :rtype: Duration

Method `to_bdt_nanoseconds`¶

def to_bdt_nanoseconds(
    self,
    /
)

Returns nanoseconds past BDT (BeiDou) Time Epoch, defined as Jan 01 2006 UTC (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS). NOTE: This function will return an error if the centuries past GST time are not zero. :rtype: int

Method `to_bdt_seconds`¶

def to_bdt_seconds(
    self,
    /
)

Returns seconds past BDT (BeiDou) Time Epoch :rtype: float

Method `to_duration_in_time_scale`¶

def to_duration_in_time_scale(
    self,
    /,
    ts
)

Returns this epoch with respect to the provided time scale. This is needed to correctly perform duration conversions in dynamical time scales (e.g. TDB). :type ts: TimeScale :rtype: Duration

Method `to_et_centuries_since_j2000`¶

def to_et_centuries_since_j2000(
    self,
    /
)

Returns the number of centuries since Ephemeris Time (ET) J2000 (used for Archinal et al. rotations) :rtype: float

Method `to_et_days_since_j2000`¶

def to_et_days_since_j2000(
    self,
    /
)

Returns the number of days since Ephemeris Time (ET) J2000 (used for Archinal et al. rotations) :rtype: float

Method `to_et_duration`¶

def to_et_duration(
    self,
    /
)

Returns the duration between J2000 and the current epoch as per NAIF SPICE.

Warning¶

The et2utc function of NAIF SPICE will assume that there are 9 leap seconds before 01 JAN 1972, as this date introduces 10 leap seconds. At the time of writing, this does not seem to be in line with IERS and the documentation in the leap seconds list.

In order to match SPICE, the as_et_duration() function will manually get rid of that difference. :rtype: Duration

Method `to_et_seconds`¶

def to_et_seconds(
    self,
    /
)

Returns the Ephemeris Time seconds past 2000 JAN 01 midnight, matches NASA/NAIF SPICE. :rtype: float

Method `to_gpst_days`¶

def to_gpst_days(
    self,
    /
)

Returns days past GPS Time Epoch, defined as UTC midnight of January 5th to 6th 1980 (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS#GPS_Time_.28GPST.29). :rtype: float

Method `to_gpst_duration`¶

def to_gpst_duration(
    self,
    /
)

Returns Duration past GPS time Epoch. :rtype: Duration

Method `to_gpst_nanoseconds`¶

def to_gpst_nanoseconds(
    self,
    /
)

Returns nanoseconds past GPS Time Epoch, defined as UTC midnight of January 5th to 6th 1980 (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS#GPS_Time_.28GPST.29). NOTE: This function will return an error if the centuries past GPST time are not zero. :rtype: int

Method `to_gpst_seconds`¶

def to_gpst_seconds(
    self,
    /
)

Returns seconds past GPS Time Epoch, defined as UTC midnight of January 5th to 6th 1980 (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS#GPS_Time_.28GPST.29). :rtype: float

Method `to_gst_days`¶

def to_gst_days(
    self,
    /
)

Returns days past GST (Galileo) Time Epoch, starting on August 21st 1999 Midnight UT (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS). :rtype: float

Method `to_gst_duration`¶

def to_gst_duration(
    self,
    /
)

Returns Duration past GST (Galileo) time Epoch. :rtype: Duration

Method `to_gst_nanoseconds`¶

def to_gst_nanoseconds(
    self,
    /
)

Returns nanoseconds past GST (Galileo) Time Epoch, starting on August 21st 1999 Midnight UT (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS). NOTE: This function will return an error if the centuries past GST time are not zero. :rtype: int

Method `to_gst_seconds`¶

def to_gst_seconds(
    self,
    /
)

Returns seconds past GST (Galileo) Time Epoch :rtype: float

Method `to_isoformat`¶

def to_isoformat(
    self,
    /
)

The standard ISO format of this epoch (six digits of subseconds) in the current time scale, refer to https://docs.rs/hifitime/latest/hifitime/efmt/format/struct.Format.html for format options. :rtype: str

Method `to_jde_et`¶

def to_jde_et(
    self,
    /,
    unit
)

:type unit: Unit :rtype: float

Method `to_jde_et_days`¶

def to_jde_et_days(
    self,
    /
)

Returns the Ephemeris Time JDE past epoch :rtype: float

Method `to_jde_et_duration`¶

def to_jde_et_duration(
    self,
    /
)

:rtype: Duration

Method `to_jde_tai`¶

def to_jde_tai(
    self,
    /,
    unit
)

Returns the Julian Days from epoch 01 Jan -4713 12:00 (noon) in desired Duration::Unit :type unit: Unit :rtype: float

Method `to_jde_tai_days`¶

def to_jde_tai_days(
    self,
    /
)

Returns the Julian days from epoch 01 Jan -4713, 12:00 (noon) as explained in "Fundamentals of astrodynamics and applications", Vallado et al. 4th edition, page 182, and on Wikipedia. :rtype: float

Method `to_jde_tai_duration`¶

def to_jde_tai_duration(
    self,
    /
)

Returns the Julian Days from epoch 01 Jan -4713 12:00 (noon) as a Duration :rtype: Duration

Method `to_jde_tai_seconds`¶

def to_jde_tai_seconds(
    self,
    /
)

Returns the Julian seconds in TAI. :rtype: float

Method `to_jde_tdb_days`¶

def to_jde_tdb_days(
    self,
    /
)

Returns the Dynamic Barycentric Time (TDB) (higher fidelity SPICE ephemeris time) whose epoch is 2000 JAN 01 noon TAI (cf. https://gssc.esa.int/navipedia/index.php/Transformations_between_Time_Systems#TDT_-_TDB.2C_TCB) :rtype: float

Method `to_jde_tdb_duration`¶

def to_jde_tdb_duration(
    self,
    /
)

:rtype: Duration

Method `to_jde_tt_days`¶

def to_jde_tt_days(
    self,
    /
)

Returns days past Julian epoch in Terrestrial Time (TT) (previously called Terrestrial Dynamical Time (TDT)) :rtype: float

Method `to_jde_tt_duration`¶

def to_jde_tt_duration(
    self,
    /
)

:rtype: Duration

Method `to_jde_utc_days`¶

def to_jde_utc_days(
    self,
    /
)

Returns the Julian days in UTC. :rtype: float

Method `to_jde_utc_duration`¶

def to_jde_utc_duration(
    self,
    /
)

Returns the Julian days in UTC as a Duration :rtype: Duration

Method `to_jde_utc_seconds`¶

def to_jde_utc_seconds(
    self,
    /
)

Returns the Julian Days in UTC seconds. :rtype: float

Method `to_mjd_tai`¶

def to_mjd_tai(
    self,
    /,
    unit
)

Returns this epoch as a duration in the requested units in MJD TAI :type unit: Unit :rtype: float

Method `to_mjd_tai_days`¶

def to_mjd_tai_days(
    self,
    /
)

as_mjd_days creates an Epoch from the provided Modified Julian Date in days as explained here. MJD epoch is Modified Julian Day at 17 November 1858 at midnight. :rtype: float

Method `to_mjd_tai_seconds`¶

def to_mjd_tai_seconds(
    self,
    /
)

Returns the Modified Julian Date in seconds TAI. :rtype: float

Method `to_mjd_tt_days`¶

def to_mjd_tt_days(
    self,
    /
)

Returns days past Modified Julian epoch in Terrestrial Time (TT) (previously called Terrestrial Dynamical Time (TDT)) :rtype: float

Method `to_mjd_tt_duration`¶

def to_mjd_tt_duration(
    self,
    /
)

:rtype: Duration

Method `to_mjd_utc`¶

def to_mjd_utc(
    self,
    /,
    unit
)

Returns the Modified Julian Date in the provided unit in UTC. :type unit: Unit :rtype: float

Method `to_mjd_utc_days`¶

def to_mjd_utc_days(
    self,
    /
)

Returns the Modified Julian Date in days UTC. :rtype: float

Method `to_mjd_utc_seconds`¶

def to_mjd_utc_seconds(
    self,
    /
)

Returns the Modified Julian Date in seconds UTC. :rtype: float

Method `to_nanoseconds_in_time_scale`¶

def to_nanoseconds_in_time_scale(
    self,
    /,
    time_scale
)

Attempts to return the number of nanoseconds since the reference epoch of the provided time scale. This will return an overflow error if more than one century has past since the reference epoch in the provided time scale. If this is not an issue, you should use epoch.to_duration_in_time_scale().to_parts() to retrieve both the centuries and the nanoseconds in that century.

:type time_scale: TimeScale :rtype: int

Method `to_qzsst_days`¶

def to_qzsst_days(
    self,
    /
)

Returns days past QZSS Time Epoch, defined as UTC midnight of January 5th to 6th 1980 (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS#GPS_Time_.28GPST.29). :rtype: float

Method `to_qzsst_duration`¶

def to_qzsst_duration(
    self,
    /
)

Returns Duration past QZSS time Epoch. :rtype: Duration

Method `to_qzsst_nanoseconds`¶

def to_qzsst_nanoseconds(
    self,
    /
)

Returns nanoseconds past QZSS Time Epoch, defined as UTC midnight of January 5th to 6th 1980 (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS#GPS_Time_.28GPST.29). NOTE: This function will return an error if the centuries past QZSST time are not zero. :rtype: int

Method `to_qzsst_seconds`¶

def to_qzsst_seconds(
    self,
    /
)

Returns seconds past QZSS Time Epoch, defined as UTC midnight of January 5th to 6th 1980 (cf. https://gssc.esa.int/navipedia/index.php/Time_References_in_GNSS#GPS_Time_.28GPST.29). :rtype: float

Method `to_rfc3339`¶

def to_rfc3339(
    self,
    /
)

Returns this epoch in UTC in the RFC3339 format :rtype: str

Method `to_tai`¶

def to_tai(
    self,
    /,
    unit
)

Returns the epoch as a floating point value in the provided unit :type unit: Unit :rtype: float

Method `to_tai_days`¶

def to_tai_days(
    self,
    /
)

Returns the number of days since J1900 in TAI :rtype: float

Method `to_tai_duration`¶

def to_tai_duration(
    self,
    /
)

Returns this time in a Duration past J1900 counted in TAI :rtype: Duration

Method `to_tai_parts`¶

def to_tai_parts(
    self,
    /
)

Returns the TAI parts of this duration :rtype: typing.Tuple

Method `to_tai_seconds`¶

def to_tai_seconds(
    self,
    /
)

Returns the number of TAI seconds since J1900 :rtype: float

Method `to_tdb_centuries_since_j2000`¶

def to_tdb_centuries_since_j2000(
    self,
    /
)

Returns the number of centuries since Dynamic Barycentric Time (TDB) J2000 (used for Archinal et al. rotations) :rtype: float

Method `to_tdb_days_since_j2000`¶

def to_tdb_days_since_j2000(
    self,
    /
)

Returns the number of days since Dynamic Barycentric Time (TDB) J2000 (used for Archinal et al. rotations) :rtype: float

Method `to_tdb_duration`¶

def to_tdb_duration(
    self,
    /
)

Returns the Dynamics Barycentric Time (TDB) as a high precision Duration since J2000

Algorithm¶

Given the embedded sine functions in the equation to compute the difference between TDB and TAI from the number of TDB seconds past J2000, one cannot solve the revert the operation analytically. Instead, we iterate until the value no longer changes.

Assume that the TAI duration is in fact the TDB seconds from J2000.
Offset to J2000 because Epoch stores everything in the J1900 but the TDB duration is in J2000.
Compute the offset g due to the TDB computation with the current value of the TDB seconds (defined in step 1).
Subtract that offset to the latest TDB seconds and store this as a new candidate for the true TDB seconds value.
Compute the difference between this candidate and the previous one. If the difference is less than one nanosecond, stop iteration.
Set the new candidate as the TDB seconds since J2000 and loop until step 5 breaks the loop, or we've done five iterations.
At this stage, we have a good approximation of the TDB seconds since J2000.
Reverse the algorithm given that approximation: compute the g offset, compute the difference between TDB and TAI, add the TT offset (32.184 s), and offset by the difference between J1900 and J2000.

:rtype: Duration

Method `to_tdb_seconds`¶

def to_tdb_seconds(
    self,
    /
)

Returns the Dynamic Barycentric Time (TDB) (higher fidelity SPICE ephemeris time) whose epoch is 2000 JAN 01 noon TAI (cf. https://gssc.esa.int/navipedia/index.php/Transformations_between_Time_Systems#TDT_-_TDB.2C_TCB) :rtype: float

Method `to_time_of_week`¶

def to_time_of_week(
    self,
    /
)

Converts this epoch into the time of week, represented as a rolling week counter into that time scale and the number of nanoseconds elapsed in current week (since closest Sunday midnight). This is usually how GNSS receivers describe a timestamp. :rtype: typing.Tuple[int]

Method `to_time_scale`¶

def to_time_scale(
    self,
    /,
    ts
)

Converts self to another time scale

As per the Rust naming convention, this borrows an Epoch and returns an owned Epoch.

:type ts: TimeScale :rtype: Epoch

Method `to_tt_centuries_j2k`¶

def to_tt_centuries_j2k(
    self,
    /
)

Returns the centuries passed J2000 TT :rtype: float

Method `to_tt_days`¶

def to_tt_days(
    self,
    /
)

Returns days past TAI epoch in Terrestrial Time (TT) (previously called Terrestrial Dynamical Time (TDT)) :rtype: float

Method `to_tt_duration`¶

def to_tt_duration(
    self,
    /
)

Returns Duration past TAI epoch in Terrestrial Time (TT). :rtype: Duration

Method `to_tt_seconds`¶

def to_tt_seconds(
    self,
    /
)

Returns seconds past TAI epoch in Terrestrial Time (TT) (previously called Terrestrial Dynamical Time (TDT)) :rtype: float

Method `to_tt_since_j2k`¶

def to_tt_since_j2k(
    self,
    /
)

Returns the duration past J2000 TT :rtype: Duration

Method `to_unix`¶

def to_unix(
    self,
    /,
    unit
)

Returns the duration since the UNIX epoch in the provided unit. :type unit: Unit :rtype: float

Method `to_unix_days`¶

def to_unix_days(
    self,
    /
)

Returns the number days since the UNIX epoch defined 01 Jan 1970 midnight UTC. :rtype: float

Method `to_unix_duration`¶

def to_unix_duration(
    self,
    /
)

Returns the Duration since the UNIX epoch UTC midnight 01 Jan 1970. :rtype: Duration

Method `to_unix_milliseconds`¶

def to_unix_milliseconds(
    self,
    /
)

Returns the number milliseconds since the UNIX epoch defined 01 Jan 1970 midnight UTC. :rtype: float

Method `to_unix_seconds`¶

def to_unix_seconds(
    self,
    /
)

Returns the number seconds since the UNIX epoch defined 01 Jan 1970 midnight UTC. :rtype: float

Method `to_utc`¶

def to_utc(
    self,
    /,
    unit
)

Returns the number of UTC seconds since the TAI epoch :type unit: Unit :rtype: float

Method `to_utc_days`¶

def to_utc_days(
    self,
    /
)

Returns the number of UTC days since the TAI epoch :rtype: float

Method `to_utc_duration`¶

def to_utc_duration(
    self,
    /
)

Returns this time in a Duration past J1900 counted in UTC :rtype: Duration

Method `to_utc_seconds`¶

def to_utc_seconds(
    self,
    /
)

Returns the number of UTC seconds since the TAI epoch :rtype: float

Method `todatetime`¶

def todatetime(
    self,
    /
)

Returns a Python datetime object from this Epoch (truncating the nanoseconds away) :rtype: datetime.datetime

Method `weekday`¶

def weekday(
    self,
    /
)

Returns weekday (uses the TAI representation for this calculation). :rtype: Weekday

Method `weekday_in_time_scale`¶

def weekday_in_time_scale(
    self,
    /,
    time_scale
)

Returns the weekday in provided time scale ASSUMING that the reference epoch of that time scale is a Monday. You probably do not want to use this. You probably either want weekday() or weekday_utc(). Several time scales do not have a reference day that's on a Monday, e.g. BDT. :type time_scale: TimeScale :rtype: Weekday

Method `weekday_utc`¶

def weekday_utc(
    self,
    /
)

Returns weekday in UTC timescale :rtype: Weekday

Method `year`¶

def year(
    self,
    /
)

Returns the number of Gregorian years of this epoch in the current time scale. :rtype: int

Method `year_days_of_year`¶

def year_days_of_year(
    self,
    /
)

Returns the year and the days in the year so far (days of year). :rtype: typing.Tuple

Class `HifitimeError`¶

class HifitimeError(
    *args,
    **kwargs
)

Ancestors (in MRO)¶

builtins.Exception
builtins.BaseException

Class `LatestLeapSeconds`¶

class LatestLeapSeconds

List of leap seconds from https://www.ietf.org/timezones/data/leap-seconds.list. This list corresponds the number of seconds in TAI to the UTC offset and to whether it was an announced leap second or not. The unannoucned leap seconds come from dat.c in the SOFA library.

Class `LeapSecondsFile`¶

class LeapSecondsFile(
    path
)

A leap second provider that uses an IERS formatted leap seconds file.

(Python documentation hints) :type path: str :rtype: LeapSecondsFile

Class `MonthName`¶

class MonthName(
    ...
)

Class variables¶

Variable `April`¶

Variable `August`¶

Variable `December`¶

Variable `February`¶

Variable `January`¶

Variable `July`¶

Variable `June`¶

Variable `March`¶

Variable `May`¶

Variable `November`¶

Variable `October`¶

Variable `September`¶

Class `ParsingError`¶

class ParsingError(
    *args,
    **kwargs
)

Ancestors (in MRO)¶

builtins.Exception
builtins.BaseException

Class `Polynomial`¶

class Polynomial(
    ...
)

Interpolation [Polynomial] used for example in [TimeScale] maintenance, precise monitoring or conversions.

(Python documentation hints) :type constant: Duration :type rate: Duration :type accel: Duration :rtype: Polynomial

Methods¶

Method `correction_duration`¶

def correction_duration(
    self,
    /,
    time_interval
)

Calculate the correction (as [Duration] once again) from [Self] and given the interpolation time interval :type time_interval: Duration :rtype: Duration

Method `from_constant_offset`¶

def from_constant_offset(
    constant
)

Create a [Polynomial] structure that is only made of a static offset :type constant: Duration :rtype: Polynomial

Method `from_constant_offset_nanoseconds`¶

def from_constant_offset_nanoseconds(
    nanos
)

Create a [Polynomial] structure from a static offset expressed in nanoseconds :type nanos: float :rtype: Polynomial

Method `from_offset_and_rate`¶

def from_offset_and_rate(
    constant,
    rate
)

Create a [Polynomial] structure from both static offset and rate of change: :type constant: Duration :type rate: Duration :rtype: Polynomial

Method `from_offset_rate_nanoseconds`¶

def from_offset_rate_nanoseconds(
    offset_ns,
    drift_ns_s
)

Create a [Polynomial] structure from a static offset and drift, in nanoseconds and nanoseconds.s⁻¹ :type offset_ns: float :type drift_ns_s: float :rtype: Polynomial

Class `TimeScale`¶

class TimeScale(
    ...
)

Enum of the different time systems available

Class variables¶

Variable `BDT`¶

Variable `ET`¶

Variable `GPST`¶

Variable `GST`¶

Variable `QZSST`¶

Variable `TAI`¶

Variable `TDB`¶

Variable `TT`¶

Variable `UTC`¶

Methods¶

Method `uses_leap_seconds`¶

def uses_leap_seconds(
    self,
    /
)

Returns true if self takes leap seconds into account :rtype: bool

Class `TimeSeries`¶

class TimeSeries(
    start,
    end,
    step,
    inclusive
)

An iterator of a sequence of evenly spaced Epochs.

(Python documentation hints) :type start: Epoch :type end: Epoch :type step: Duration :type inclusive: bool :rtype: TimeSeries

Class `Unit`¶

class Unit(
    ...
)

An Enum to perform time unit conversions.

Class variables¶

Variable `Century`¶

Variable `Day`¶

Variable `Hour`¶

Variable `Microsecond`¶

Variable `Millisecond`¶

Variable `Minute`¶

Variable `Nanosecond`¶

Variable `Second`¶

Variable `Week`¶

Methods¶

Method `from_seconds`¶

def from_seconds(
    self,
    /
)

Method `in_seconds`¶

def in_seconds(
    self,
    /
)

Class `Ut1Provider`¶

class Ut1Provider

A structure storing all of the TAI-UT1 data

Class `Weekday`¶

class Weekday(
    ...
)

Class variables¶

Variable `Friday`¶

Variable `Monday`¶

Variable `Saturday`¶

Variable `Sunday`¶

Variable `Thursday`¶

Variable `Tuesday`¶

Variable `Wednesday`¶

Generated by pdoc 0.11.6 (https://pdoc3.github.io).

Module anise.time¶

Classes¶

Class Duration¶

Methods¶

Method EPSILON¶

Method MAX¶

Method MIN¶

Method MIN_NEGATIVE¶

Method MIN_POSITIVE¶

Method ZERO¶

Method abs¶

Method approx¶

Example¶

Method ceil¶

Example¶

Method decompose¶

Method floor¶

Example¶

Method from_all_parts¶

Method from_parts¶

Method from_total_nanoseconds¶

Method is_negative¶

Method max¶

Method min¶

Method round¶

Example¶

Method signum¶

Method to_parts¶

Method to_seconds¶

Method to_unit¶

Method total_nanoseconds¶

Class DurationError¶

Ancestors (in MRO)¶

Class Epoch¶

Instance variables¶

Variable duration¶

Variable time_scale¶

Methods¶

Method ceil¶

Example¶

Method day_of_year¶

Method duration_in_year¶

Method floor¶

Example¶

Method from_bdt_days¶

Method from_bdt_nanoseconds¶

Method from_bdt_seconds¶

Method from_et_duration¶

Method from_et_seconds¶

Method from_gpst_days¶

Method from_gpst_nanoseconds¶

Method from_gpst_seconds¶

Method from_gregorian¶

Method from_gregorian_at_midnight¶

Method from_gregorian_at_noon¶

Method from_gregorian_utc¶

Method from_gst_days¶

Method from_gst_nanoseconds¶

Method from_gst_seconds¶

Method from_jde_et¶

Method from_jde_tai¶

Method from_jde_tdb¶

Method from_jde_utc¶

Method from_mjd_tai¶

Method from_mjd_utc¶

Method from_ptp_duration¶

Method from_ptp_nanoseconds¶

Method from_ptp_seconds¶

Method from_qzsst_days¶

Method from_qzsst_nanoseconds¶

Method from_qzsst_seconds¶

Method from_tai_days¶

Method from_tai_duration¶

Method from_tai_parts¶

Method from_tai_seconds¶

Method from_tdb_duration¶

Method from_tdb_seconds¶

Method from_tt_duration¶

Method from_tt_seconds¶

Method from_unix_milliseconds¶

Module `anise.time`¶

Class `Duration`¶

Method `EPSILON`¶

Method `MAX`¶

Method `MIN`¶

Method `MIN_NEGATIVE`¶

Method `MIN_POSITIVE`¶

Method `ZERO`¶

Method `abs`¶

Method `approx`¶

Method `ceil`¶

Method `decompose`¶

Method `floor`¶

Method `from_all_parts`¶

Method `from_parts`¶

Method `from_total_nanoseconds`¶

Method `is_negative`¶

Method `max`¶

Method `min`¶

Method `round`¶

Method `signum`¶

Method `to_parts`¶

Method `to_seconds`¶

Method `to_unit`¶

Method `total_nanoseconds`¶

Class `DurationError`¶

Class `Epoch`¶

Variable `duration`¶

Variable `time_scale`¶

Method `ceil`¶

Method `day_of_year`¶

Method `duration_in_year`¶

Method `floor`¶

Method `from_bdt_days`¶

Method `from_bdt_nanoseconds`¶

Method `from_bdt_seconds`¶

Method `from_et_duration`¶

Method `from_et_seconds`¶

Method `from_gpst_days`¶

Method `from_gpst_nanoseconds`¶

Method `from_gpst_seconds`¶

Method `from_gregorian`¶

Method `from_gregorian_at_midnight`¶

Method `from_gregorian_at_noon`¶

Method `from_gregorian_utc`¶

Method `from_gst_days`¶

Method `from_gst_nanoseconds`¶

Method `from_gst_seconds`¶

Method `from_jde_et`¶

Method `from_jde_tai`¶

Method `from_jde_tdb`¶

Method `from_jde_utc`¶

Method `from_mjd_tai`¶

Method `from_mjd_utc`¶

Method `from_ptp_duration`¶

Method `from_ptp_nanoseconds`¶

Method `from_ptp_seconds`¶

Method `from_qzsst_days`¶

Method `from_qzsst_nanoseconds`¶

Method `from_qzsst_seconds`¶

Method `from_tai_days`¶

Method `from_tai_duration`¶

Method `from_tai_parts`¶

Method `from_tai_seconds`¶

Method `from_tdb_duration`¶

Method `from_tdb_seconds`¶

Method `from_tt_duration`¶

Method `from_tt_seconds`¶

Method `from_unix_milliseconds`¶

Method `from_unix_seconds`¶

Method `from_utc_days`¶

Method `from_utc_seconds`¶

Method `fromdatetime`¶

Method `hours`¶

Method `init_from_bdt_days`¶

Method `init_from_bdt_nanoseconds`¶

Method `init_from_bdt_seconds`¶

Method `init_from_et_duration`¶

Method `init_from_et_seconds`¶

Method `init_from_gpst_days`¶