# Licensed under a 3-clause BSD style license - see LICENSE.rst
import datetime
import fnmatch
import re
import time
import warnings
from collections import OrderedDict, defaultdict
from decimal import Decimal
import erfa
import numpy as np
import astropy.units as u
from astropy.utils.decorators import classproperty, lazyproperty
from astropy.utils.exceptions import AstropyDeprecationWarning
from . import _parse_times, conf, utils
from .utils import day_frac, quantity_day_frac, two_product, two_sum
__all__ = [
"TimeFormat",
"TimeJD",
"TimeMJD",
"TimeFromEpoch",
"TimeUnix",
"TimeUnixTai",
"TimeCxcSec",
"TimeGPS",
"TimeDecimalYear",
"TimePlotDate",
"TimeUnique",
"TimeDatetime",
"TimeString",
"TimeISO",
"TimeISOT",
"TimeFITS",
"TimeYearDayTime",
"TimeEpochDate",
"TimeBesselianEpoch",
"TimeJulianEpoch",
"TimeDeltaFormat",
"TimeDeltaSec",
"TimeDeltaJD",
"TimeEpochDateString",
"TimeBesselianEpochString",
"TimeJulianEpochString",
"TIME_FORMATS",
"TIME_DELTA_FORMATS",
"TimezoneInfo",
"TimeDeltaDatetime",
"TimeDatetime64",
"TimeYMDHMS",
"TimeNumeric",
"TimeDeltaNumeric",
]
__doctest_skip__ = ["TimePlotDate"]
# These both get filled in at end after TimeFormat subclasses defined.
# Use an OrderedDict to fix the order in which formats are tried.
# This ensures, e.g., that 'isot' gets tried before 'fits'.
TIME_FORMATS = OrderedDict()
TIME_DELTA_FORMATS = OrderedDict()
# Translations between deprecated FITS timescales defined by
# Rots et al. 2015, A&A 574:A36, and timescales used here.
FITS_DEPRECATED_SCALES = {
"TDT": "tt",
"ET": "tt",
"GMT": "utc",
"UT": "utc",
"IAT": "tai",
}
def _regexify_subfmts(subfmts):
"""
Iterate through each of the sub-formats and try substituting simple
regular expressions for the strptime codes for year, month, day-of-month,
hour, minute, second. If no % characters remain then turn the final string
into a compiled regex. This assumes time formats do not have a % in them.
This is done both to speed up parsing of strings and to allow mixed formats
where strptime does not quite work well enough.
"""
new_subfmts = []
for subfmt_tuple in subfmts:
subfmt_in = subfmt_tuple[1]
if isinstance(subfmt_in, str):
for strptime_code, regex in (
("%Y", r"(?P<year>\d\d\d\d)"),
("%m", r"(?P<mon>\d{1,2})"),
("%d", r"(?P<mday>\d{1,2})"),
("%H", r"(?P<hour>\d{1,2})"),
("%M", r"(?P<min>\d{1,2})"),
("%S", r"(?P<sec>\d{1,2})"),
):
subfmt_in = subfmt_in.replace(strptime_code, regex)
if "%" not in subfmt_in:
subfmt_tuple = (
subfmt_tuple[0],
re.compile(subfmt_in + "$"),
subfmt_tuple[2],
)
new_subfmts.append(subfmt_tuple)
return tuple(new_subfmts)
[docs]class TimeJD(TimeNumeric):
"""
Julian Date time format.
This represents the number of days since the beginning of
the Julian Period.
For example, 2451544.5 in JD is midnight on January 1, 2000.
"""
name = "jd"
[docs] def set_jds(self, val1, val2):
self._check_scale(self._scale) # Validate scale.
self.jd1, self.jd2 = day_frac(val1, val2)
[docs]class TimeMJD(TimeNumeric):
"""
Modified Julian Date time format.
This represents the number of days since midnight on November 17, 1858.
For example, 51544.0 in MJD is midnight on January 1, 2000.
"""
name = "mjd"
[docs] def set_jds(self, val1, val2):
self._check_scale(self._scale) # Validate scale.
jd1, jd2 = day_frac(val1, val2)
jd1 += erfa.DJM0 # erfa.DJM0=2400000.5 (from erfam.h).
self.jd1, self.jd2 = day_frac(jd1, jd2)
[docs] def to_value(self, **kwargs):
jd1 = self.jd1 - erfa.DJM0 # This cannot lose precision.
jd2 = self.jd2
return super().to_value(jd1=jd1, jd2=jd2, **kwargs)
value = property(to_value)
[docs]class TimeDecimalYear(TimeNumeric):
"""
Time as a decimal year, with integer values corresponding to midnight
of the first day of each year. For example 2000.5 corresponds to the
ISO time '2000-07-02 00:00:00'.
"""
name = "decimalyear"
[docs] def set_jds(self, val1, val2):
self._check_scale(self._scale) # Validate scale.
sum12, err12 = two_sum(val1, val2)
iy_start = np.trunc(sum12).astype(int)
extra, y_frac = two_sum(sum12, -iy_start)
y_frac += extra + err12
val = (val1 + val2).astype(np.double)
iy_start = np.trunc(val).astype(int)
imon = np.ones_like(iy_start)
iday = np.ones_like(iy_start)
ihr = np.zeros_like(iy_start)
imin = np.zeros_like(iy_start)
isec = np.zeros_like(y_frac)
# Possible enhancement: use np.unique to only compute start, stop
# for unique values of iy_start.
scale = self.scale.upper().encode("ascii")
jd1_start, jd2_start = erfa.dtf2d(scale, iy_start, imon, iday, ihr, imin, isec)
jd1_end, jd2_end = erfa.dtf2d(scale, iy_start + 1, imon, iday, ihr, imin, isec)
t_start = Time(jd1_start, jd2_start, scale=self.scale, format="jd")
t_end = Time(jd1_end, jd2_end, scale=self.scale, format="jd")
t_frac = t_start + (t_end - t_start) * y_frac
self.jd1, self.jd2 = day_frac(t_frac.jd1, t_frac.jd2)
[docs] def to_value(self, **kwargs):
scale = self.scale.upper().encode("ascii")
iy_start, ims, ids, ihmsfs = erfa.d2dtf(
scale, 0, self.jd1, self.jd2_filled # precision=0
)
imon = np.ones_like(iy_start)
iday = np.ones_like(iy_start)
ihr = np.zeros_like(iy_start)
imin = np.zeros_like(iy_start)
isec = np.zeros_like(self.jd1)
# Possible enhancement: use np.unique to only compute start, stop
# for unique values of iy_start.
scale = self.scale.upper().encode("ascii")
jd1_start, jd2_start = erfa.dtf2d(scale, iy_start, imon, iday, ihr, imin, isec)
jd1_end, jd2_end = erfa.dtf2d(scale, iy_start + 1, imon, iday, ihr, imin, isec)
# Trying to be precise, but more than float64 not useful.
dt = (self.jd1 - jd1_start) + (self.jd2 - jd2_start)
dt_end = (jd1_end - jd1_start) + (jd2_end - jd2_start)
decimalyear = iy_start + dt / dt_end
return super().to_value(jd1=decimalyear, jd2=np.float64(0.0), **kwargs)
value = property(to_value)
[docs]class TimeFromEpoch(TimeNumeric):
"""
Base class for times that represent the interval from a particular
epoch as a floating point multiple of a unit time interval (e.g. seconds
or days).
"""
@classproperty(lazy=True)
def _epoch(cls):
# Ideally we would use `def epoch(cls)` here and not have the instance
# property below. However, this breaks the sphinx API docs generation
# in a way that was not resolved. See #10406 for details.
return Time(
cls.epoch_val,
cls.epoch_val2,
scale=cls.epoch_scale,
format=cls.epoch_format,
)
@property
def epoch(self):
"""Reference epoch time from which the time interval is measured"""
return self._epoch
[docs] def set_jds(self, val1, val2):
"""
Initialize the internal jd1 and jd2 attributes given val1 and val2.
For an TimeFromEpoch subclass like TimeUnix these will be floats giving
the effective seconds since an epoch time (e.g. 1970-01-01 00:00:00).
"""
# Form new JDs based on epoch time + time from epoch (converted to JD).
# One subtlety that might not be obvious is that 1.000 Julian days in
# UTC can be 86400 or 86401 seconds. For the TimeUnix format the
# assumption is that every day is exactly 86400 seconds, so this is, in
# principle, doing the math incorrectly, *except* that it matches the
# definition of Unix time which does not include leap seconds.
# note: use divisor=1./self.unit, since this is either 1 or 1/86400,
# and 1/86400 is not exactly representable as a float64, so multiplying
# by that will cause rounding errors. (But inverting it as a float64
# recovers the exact number)
day, frac = day_frac(val1, val2, divisor=1.0 / self.unit)
jd1 = self.epoch.jd1 + day
jd2 = self.epoch.jd2 + frac
# For the usual case that scale is the same as epoch_scale, we only need
# to ensure that abs(jd2) <= 0.5. Since abs(self.epoch.jd2) <= 0.5 and
# abs(frac) <= 0.5, we can do simple (fast) checks and arithmetic here
# without another call to day_frac(). Note also that `round(jd2.item())`
# is about 10x faster than `np.round(jd2)`` for a scalar.
if self.epoch.scale == self.scale:
jd1_extra = np.round(jd2) if jd2.shape else round(jd2.item())
jd1 += jd1_extra
jd2 -= jd1_extra
self.jd1, self.jd2 = jd1, jd2
return
# Create a temporary Time object corresponding to the new (jd1, jd2) in
# the epoch scale (e.g. UTC for TimeUnix) then convert that to the
# desired time scale for this object.
#
# A known limitation is that the transform from self.epoch_scale to
# self.scale cannot involve any metadata like lat or lon.
try:
tm = getattr(
Time(jd1, jd2, scale=self.epoch_scale, format="jd"), self.scale
)
except Exception as err:
raise ScaleValueError(
f"Cannot convert from '{self.name}' epoch scale '{self.epoch_scale}' "
f"to specified scale '{self.scale}', got error:\n{err}"
) from err
self.jd1, self.jd2 = day_frac(tm._time.jd1, tm._time.jd2)
[docs] def to_value(self, parent=None, **kwargs):
# Make sure that scale is the same as epoch scale so we can just
# subtract the epoch and convert
if self.scale != self.epoch_scale:
if parent is None:
raise ValueError("cannot compute value without parent Time object")
try:
tm = getattr(parent, self.epoch_scale)
except Exception as err:
raise ScaleValueError(
f"Cannot convert from '{self.name}' epoch scale "
f"'{self.epoch_scale}' to specified scale '{self.scale}', "
f"got error:\n{err}"
) from err
jd1, jd2 = tm._time.jd1, tm._time.jd2
else:
jd1, jd2 = self.jd1, self.jd2
# This factor is guaranteed to be exactly representable, which
# means time_from_epoch1 is calculated exactly.
factor = 1.0 / self.unit
time_from_epoch1 = (jd1 - self.epoch.jd1) * factor
time_from_epoch2 = (jd2 - self.epoch.jd2) * factor
return super().to_value(jd1=time_from_epoch1, jd2=time_from_epoch2, **kwargs)
value = property(to_value)
@property
def _default_scale(self):
return self.epoch_scale
[docs]class TimeUnix(TimeFromEpoch):
"""
Unix time (UTC): seconds from 1970-01-01 00:00:00 UTC, ignoring leap seconds.
For example, 946684800.0 in Unix time is midnight on January 1, 2000.
NOTE: this quantity is not exactly unix time and differs from the strict
POSIX definition by up to 1 second on days with a leap second. POSIX
unix time actually jumps backward by 1 second at midnight on leap second
days while this class value is monotonically increasing at 86400 seconds
per UTC day.
"""
name = "unix"
unit = 1.0 / erfa.DAYSEC # in days (1 day == 86400 seconds)
epoch_val = "1970-01-01 00:00:00"
epoch_val2 = None
epoch_scale = "utc"
epoch_format = "iso"
[docs]class TimeUnixTai(TimeUnix):
"""
Unix time (TAI): SI seconds elapsed since 1970-01-01 00:00:00 TAI (see caveats).
This will generally differ from standard (UTC) Unix time by the cumulative
integral number of leap seconds introduced into UTC since 1972-01-01 UTC
plus the initial offset of 10 seconds at that date.
This convention matches the definition of linux CLOCK_TAI
(https://www.cl.cam.ac.uk/~mgk25/posix-clocks.html),
and the Precision Time Protocol
(https://en.wikipedia.org/wiki/Precision_Time_Protocol), which
is also used by the White Rabbit protocol in High Energy Physics:
https://white-rabbit.web.cern.ch.
Caveats:
- Before 1972, fractional adjustments to UTC were made, so the difference
between ``unix`` and ``unix_tai`` time is no longer an integer.
- Because of the fractional adjustments, to be very precise, ``unix_tai``
is the number of seconds since ``1970-01-01 00:00:00 TAI`` or equivalently
``1969-12-31 23:59:51.999918 UTC``. The difference between TAI and UTC
at that epoch was 8.000082 sec.
- On the day of a positive leap second the difference between ``unix`` and
``unix_tai`` times increases linearly through the day by 1.0. See also the
documentation for the `~astropy.time.TimeUnix` class.
- Negative leap seconds are possible, though none have been needed to date.
Examples
--------
>>> # get the current offset between TAI and UTC
>>> from astropy.time import Time
>>> t = Time('2020-01-01', scale='utc')
>>> t.unix_tai - t.unix
37.0
>>> # Before 1972, the offset between TAI and UTC was not integer
>>> t = Time('1970-01-01', scale='utc')
>>> t.unix_tai - t.unix # doctest: +FLOAT_CMP
8.000082
>>> # Initial offset of 10 seconds in 1972
>>> t = Time('1972-01-01', scale='utc')
>>> t.unix_tai - t.unix
10.0
"""
name = "unix_tai"
epoch_val = "1970-01-01 00:00:00"
epoch_scale = "tai"
[docs]class TimeCxcSec(TimeFromEpoch):
"""
Chandra X-ray Center seconds from 1998-01-01 00:00:00 TT.
For example, 63072064.184 is midnight on January 1, 2000.
"""
name = "cxcsec"
unit = 1.0 / erfa.DAYSEC # in days (1 day == 86400 seconds)
epoch_val = "1998-01-01 00:00:00"
epoch_val2 = None
epoch_scale = "tt"
epoch_format = "iso"
[docs]class TimeGPS(TimeFromEpoch):
"""GPS time: seconds from 1980-01-06 00:00:00 UTC
For example, 630720013.0 is midnight on January 1, 2000.
Notes
=====
This implementation is strictly a representation of the number of seconds
(including leap seconds) since midnight UTC on 1980-01-06. GPS can also be
considered as a time scale which is ahead of TAI by a fixed offset
(to within about 100 nanoseconds).
For details, see https://www.usno.navy.mil/USNO/time/gps/usno-gps-time-transfer
"""
name = "gps"
unit = 1.0 / erfa.DAYSEC # in days (1 day == 86400 seconds)
epoch_val = "1980-01-06 00:00:19"
# above epoch is the same as Time('1980-01-06 00:00:00', scale='utc').tai
epoch_val2 = None
epoch_scale = "tai"
epoch_format = "iso"
[docs]class TimePlotDate(TimeFromEpoch):
"""
Matplotlib `~matplotlib.pyplot.plot_date` input:
1 + number of days from 0001-01-01 00:00:00 UTC
This can be used directly in the matplotlib `~matplotlib.pyplot.plot_date`
function::
>>> import matplotlib.pyplot as plt
>>> jyear = np.linspace(2000, 2001, 20)
>>> t = Time(jyear, format='jyear', scale='utc')
>>> plt.plot_date(t.plot_date, jyear)
>>> plt.gcf().autofmt_xdate() # orient date labels at a slant
>>> plt.draw()
For example, 730120.0003703703 is midnight on January 1, 2000.
"""
# This corresponds to the zero reference time for matplotlib plot_date().
# Note that TAI and UTC are equivalent at the reference time.
name = "plot_date"
unit = 1.0
epoch_val = 1721424.5 # Time('0001-01-01 00:00:00', scale='tai').jd - 1
epoch_val2 = None
epoch_scale = "utc"
epoch_format = "jd"
@lazyproperty
def epoch(self):
"""Reference epoch time from which the time interval is measured"""
try:
# Matplotlib >= 3.3 has a get_epoch() function
from matplotlib.dates import get_epoch
except ImportError:
# If no get_epoch() then the epoch is '0001-01-01'
_epoch = self._epoch
else:
# Get the matplotlib date epoch as an ISOT string in UTC
epoch_utc = get_epoch()
from erfa import ErfaWarning
with warnings.catch_warnings():
# Catch possible dubious year warnings from erfa
warnings.filterwarnings("ignore", category=ErfaWarning)
_epoch = Time(epoch_utc, scale="utc", format="isot")
_epoch.format = "jd"
return _epoch
class TimeStardate(TimeFromEpoch):
"""
Stardate: date units from 2318-07-05 12:00:00 UTC.
For example, stardate 41153.7 is 00:52 on April 30, 2363.
See http://trekguide.com/Stardates.htm#TNG for calculations and reference points
"""
name = "stardate"
unit = 0.397766856 # Stardate units per day
epoch_val = "2318-07-05 11:00:00" # Date and time of stardate 00000.00
epoch_val2 = None
epoch_scale = "tai"
epoch_format = "iso"
[docs]class TimeUnique(TimeFormat):
"""
Base class for time formats that can uniquely create a time object
without requiring an explicit format specifier. This class does
nothing but provide inheritance to identify a class as unique.
"""
class TimeAstropyTime(TimeUnique):
"""
Instantiate date from an Astropy Time object (or list thereof).
This is purely for instantiating from a Time object. The output
format is the same as the first time instance.
"""
name = "astropy_time"
def __new__(
cls, val1, val2, scale, precision, in_subfmt, out_subfmt, from_jd=False
):
"""
Use __new__ instead of __init__ to output a class instance that
is the same as the class of the first Time object in the list.
"""
val1_0 = val1.flat[0]
if not (
isinstance(val1_0, Time)
and all(type(val) is type(val1_0) for val in val1.flat)
):
raise TypeError(
f"Input values for {cls.name} class must all be the same "
"astropy Time type."
)
if scale is None:
scale = val1_0.scale
if val1.shape:
vals = [getattr(val, scale)._time for val in val1]
jd1 = np.concatenate([np.atleast_1d(val.jd1) for val in vals])
jd2 = np.concatenate([np.atleast_1d(val.jd2) for val in vals])
# Collect individual location values and merge into a single location.
if any(tm.location is not None for tm in val1):
if any(tm.location is None for tm in val1):
raise ValueError(
"cannot concatenate times unless all locations "
"are set or no locations are set"
)
locations = []
for tm in val1:
location = np.broadcast_to(
tm.location, tm._time.jd1.shape, subok=True
)
locations.append(np.atleast_1d(location))
location = np.concatenate(locations)
else:
location = None
else:
val = getattr(val1_0, scale)._time
jd1, jd2 = val.jd1, val.jd2
location = val1_0.location
OutTimeFormat = val1_0._time.__class__
self = OutTimeFormat(
jd1, jd2, scale, precision, in_subfmt, out_subfmt, from_jd=True
)
# Make a temporary hidden attribute to transfer location back to the
# parent Time object where it needs to live.
self._location = location
return self
[docs]class TimeDatetime(TimeUnique):
"""
Represent date as Python standard library `~datetime.datetime` object
Example::
>>> from astropy.time import Time
>>> from datetime import datetime
>>> t = Time(datetime(2000, 1, 2, 12, 0, 0), scale='utc')
>>> t.iso
'2000-01-02 12:00:00.000'
>>> t.tt.datetime
datetime.datetime(2000, 1, 2, 12, 1, 4, 184000)
"""
name = "datetime"
def _check_val_type(self, val1, val2):
if not all(isinstance(val, datetime.datetime) for val in val1.flat):
raise TypeError(
f"Input values for {self.name} class must be datetime objects"
)
if val2 is not None:
raise ValueError(
f"{self.name} objects do not accept a val2 but you provided {val2}"
)
return val1, None
[docs] def set_jds(self, val1, val2):
"""Convert datetime object contained in val1 to jd1, jd2"""
# Iterate through the datetime objects, getting year, month, etc.
iterator = np.nditer(
[val1, None, None, None, None, None, None],
flags=["refs_ok", "zerosize_ok"],
op_dtypes=[None] + 5 * [np.intc] + [np.double],
)
for val, iy, im, id, ihr, imin, dsec in iterator:
dt = val.item()
if dt.tzinfo is not None:
dt = (dt - dt.utcoffset()).replace(tzinfo=None)
iy[...] = dt.year
im[...] = dt.month
id[...] = dt.day
ihr[...] = dt.hour
imin[...] = dt.minute
dsec[...] = dt.second + dt.microsecond / 1e6
jd1, jd2 = erfa.dtf2d(
self.scale.upper().encode("ascii"), *iterator.operands[1:]
)
self.jd1, self.jd2 = day_frac(jd1, jd2)
[docs] def to_value(self, timezone=None, parent=None, out_subfmt=None):
"""
Convert to (potentially timezone-aware) `~datetime.datetime` object.
If ``timezone`` is not ``None``, return a timezone-aware datetime
object.
Parameters
----------
timezone : {`~datetime.tzinfo`, None}, optional
If not `None`, return timezone-aware datetime.
Returns
-------
`~datetime.datetime`
If ``timezone`` is not ``None``, output will be timezone-aware.
"""
if out_subfmt is not None:
# Out_subfmt not allowed for this format, so raise the standard
# exception by trying to validate the value.
self._select_subfmts(out_subfmt)
if timezone is not None:
if self._scale != "utc":
raise ScaleValueError(
f"scale is {self._scale}, must be 'utc' when timezone is supplied."
)
# Rather than define a value property directly, we have a function,
# since we want to be able to pass in timezone information.
scale = self.scale.upper().encode("ascii")
iys, ims, ids, ihmsfs = erfa.d2dtf(
scale, 6, self.jd1, self.jd2_filled # 6 for microsec
)
ihrs = ihmsfs["h"]
imins = ihmsfs["m"]
isecs = ihmsfs["s"]
ifracs = ihmsfs["f"]
iterator = np.nditer(
[iys, ims, ids, ihrs, imins, isecs, ifracs, None],
flags=["refs_ok", "zerosize_ok"],
op_dtypes=7 * [None] + [object],
)
for iy, im, id, ihr, imin, isec, ifracsec, out in iterator:
if isec >= 60:
raise ValueError(
f"Time {(iy, im, id, ihr, imin, isec, ifracsec)} is within "
"a leap second but datetime does not support leap seconds"
)
if timezone is not None:
out[...] = datetime.datetime(
iy, im, id, ihr, imin, isec, ifracsec, tzinfo=TimezoneInfo()
).astimezone(timezone)
else:
out[...] = datetime.datetime(iy, im, id, ihr, imin, isec, ifracsec)
return self.mask_if_needed(iterator.operands[-1])
value = property(to_value)
[docs]class TimeYMDHMS(TimeUnique):
"""
ymdhms: A Time format to represent Time as year, month, day, hour,
minute, second (thus the name ymdhms).
Acceptable inputs must have keys or column names in the "YMDHMS" set of
``year``, ``month``, ``day`` ``hour``, ``minute``, ``second``:
- Dict with keys in the YMDHMS set
- NumPy structured array, record array or astropy Table, or single row
of those types, with column names in the YMDHMS set
One can supply a subset of the YMDHMS values, for instance only 'year',
'month', and 'day'. Inputs have the following defaults::
'month': 1, 'day': 1, 'hour': 0, 'minute': 0, 'second': 0
When the input is supplied as a ``dict`` then each value can be either a
scalar value or an array. The values will be broadcast to a common shape.
Example::
>>> from astropy.time import Time
>>> t = Time({'year': 2015, 'month': 2, 'day': 3,
... 'hour': 12, 'minute': 13, 'second': 14.567},
... scale='utc')
>>> t.iso
'2015-02-03 12:13:14.567'
>>> t.ymdhms.year
2015
"""
name = "ymdhms"
def _check_val_type(self, val1, val2):
"""
This checks inputs for the YMDHMS format.
It is bit more complex than most format checkers because of the flexible
input that is allowed. Also, it actually coerces ``val1`` into an appropriate
dict of ndarrays that can be used easily by ``set_jds()``. This is useful
because it makes it easy to get default values in that routine.
Parameters
----------
val1 : ndarray or None
val2 : ndarray or None
Returns
-------
val1_as_dict, val2 : val1 as dict or None, val2 is always None
"""
if val2 is not None:
raise ValueError("val2 must be None for ymdhms format")
ymdhms = ["year", "month", "day", "hour", "minute", "second"]
if val1.dtype.names:
# Convert to a dict of ndarray
val1_as_dict = {name: val1[name] for name in val1.dtype.names}
elif val1.shape == (0,):
# Input was empty list [], so set to None and set_jds will handle this
return None, None
elif (
val1.dtype.kind == "O"
and val1.shape == ()
and isinstance(val1.item(), dict)
):
# Code gets here for input as a dict. The dict input
# can be either scalar values or N-d arrays.
# Extract the item (which is a dict) and broadcast values to the
# same shape here.
names = val1.item().keys()
values = val1.item().values()
val1_as_dict = {
name: value for name, value in zip(names, np.broadcast_arrays(*values))
}
else:
raise ValueError("input must be dict or table-like")
# Check that the key names now are good.
names = val1_as_dict.keys()
required_names = ymdhms[: len(names)]
def comma_repr(vals):
return ", ".join(repr(val) for val in vals)
bad_names = set(names) - set(ymdhms)
if bad_names:
raise ValueError(
f"{comma_repr(bad_names)} not allowed as YMDHMS key name(s)"
)
if set(names) != set(required_names):
raise ValueError(
f"for {len(names)} input key names "
f"you must supply {comma_repr(required_names)}"
)
return val1_as_dict, val2
[docs] def set_jds(self, val1, val2):
if val1 is None:
# Input was empty list []
jd1 = np.array([], dtype=np.float64)
jd2 = np.array([], dtype=np.float64)
else:
jd1, jd2 = erfa.dtf2d(
self.scale.upper().encode("ascii"),
val1["year"],
val1.get("month", 1),
val1.get("day", 1),
val1.get("hour", 0),
val1.get("minute", 0),
val1.get("second", 0),
)
self.jd1, self.jd2 = day_frac(jd1, jd2)
@property
def value(self):
scale = self.scale.upper().encode("ascii")
iys, ims, ids, ihmsfs = erfa.d2dtf(scale, 9, self.jd1, self.jd2_filled)
out = np.empty(
self.jd1.shape,
dtype=[
("year", "i4"),
("month", "i4"),
("day", "i4"),
("hour", "i4"),
("minute", "i4"),
("second", "f8"),
],
)
out["year"] = iys
out["month"] = ims
out["day"] = ids
out["hour"] = ihmsfs["h"]
out["minute"] = ihmsfs["m"]
out["second"] = ihmsfs["s"] + ihmsfs["f"] * 10 ** (-9)
out = out.view(np.recarray)
return self.mask_if_needed(out)
[docs]class TimezoneInfo(datetime.tzinfo):
"""
Subclass of the `~datetime.tzinfo` object, used in the
to_datetime method to specify timezones.
It may be safer in most cases to use a timezone database package like
pytz rather than defining your own timezones - this class is mainly
a workaround for users without pytz.
"""
@u.quantity_input(utc_offset=u.day, dst=u.day)
def __init__(self, utc_offset=0 * u.day, dst=0 * u.day, tzname=None):
"""
Parameters
----------
utc_offset : `~astropy.units.Quantity`, optional
Offset from UTC in days. Defaults to zero.
dst : `~astropy.units.Quantity`, optional
Daylight Savings Time offset in days. Defaults to zero
(no daylight savings).
tzname : str or None, optional
Name of timezone
Examples
--------
>>> from datetime import datetime
>>> from astropy.time import TimezoneInfo # Specifies a timezone
>>> import astropy.units as u
>>> utc = TimezoneInfo() # Defaults to UTC
>>> utc_plus_one_hour = TimezoneInfo(utc_offset=1*u.hour) # UTC+1
>>> dt_aware = datetime(2000, 1, 1, 0, 0, 0, tzinfo=utc_plus_one_hour)
>>> print(dt_aware)
2000-01-01 00:00:00+01:00
>>> print(dt_aware.astimezone(utc))
1999-12-31 23:00:00+00:00
"""
if utc_offset == 0 and dst == 0 and tzname is None:
tzname = "UTC"
self._utcoffset = datetime.timedelta(utc_offset.to_value(u.day))
self._tzname = tzname
self._dst = datetime.timedelta(dst.to_value(u.day))
[docs] def utcoffset(self, dt):
return self._utcoffset
[docs] def tzname(self, dt):
return str(self._tzname)
[docs] def dst(self, dt):
return self._dst
[docs]class TimeString(TimeUnique):
"""
Base class for string-like time representations.
This class assumes that anything following the last decimal point to the
right is a fraction of a second.
**Fast C-based parser**
Time format classes can take advantage of a fast C-based parser if the times
are represented as fixed-format strings with year, month, day-of-month,
hour, minute, second, OR year, day-of-year, hour, minute, second. This can
be a factor of 20 or more faster than the pure Python parser.
Fixed format means that the components always have the same number of
characters. The Python parser will accept ``2001-9-2`` as a date, but the C
parser would require ``2001-09-02``.
A subclass in this case must define a class attribute ``fast_parser_pars``
which is a `dict` with all of the keys below. An inherited attribute is not
checked, only an attribute in the class ``__dict__``.
- ``delims`` (tuple of int): ASCII code for character at corresponding
``starts`` position (0 => no character)
- ``starts`` (tuple of int): position where component starts (including
delimiter if present). Use -1 for the month component for format that use
day of year.
- ``stops`` (tuple of int): position where component ends. Use -1 to
continue to end of string, or for the month component for formats that use
day of year.
- ``break_allowed`` (tuple of int): if true (1) then the time string can
legally end just before the corresponding component (e.g. "2000-01-01"
is a valid time but "2000-01-01 12" is not).
- ``has_day_of_year`` (int): 0 if dates have year, month, day; 1 if year,
day-of-year
"""
def __init_subclass__(cls, **kwargs):
if "fast_parser_pars" in cls.__dict__:
fpp = cls.fast_parser_pars
fpp = np.array(
list(
zip(
map(chr, fpp["delims"]),
fpp["starts"],
fpp["stops"],
fpp["break_allowed"],
)
),
_parse_times.dt_pars,
)
if cls.fast_parser_pars["has_day_of_year"]:
fpp["start"][1] = fpp["stop"][1] = -1
cls._fast_parser = _parse_times.create_parser(fpp)
super().__init_subclass__(**kwargs)
def _check_val_type(self, val1, val2):
if val1.dtype.kind not in ("S", "U") and val1.size:
raise TypeError(f"Input values for {self.name} class must be strings")
if val2 is not None:
raise ValueError(
f"{self.name} objects do not accept a val2 but you provided {val2}"
)
return val1, None
[docs] def parse_string(self, timestr, subfmts):
"""Read time from a single string, using a set of possible formats."""
# Datetime components required for conversion to JD by ERFA, along
# with the default values.
components = ("year", "mon", "mday", "hour", "min", "sec")
defaults = (None, 1, 1, 0, 0, 0)
# Assume that anything following "." on the right side is a
# floating fraction of a second.
try:
idot = timestr.rindex(".")
except Exception:
timestr_has_fractional_digits = False
else:
timestr, fracsec = timestr[:idot], timestr[idot:]
fracsec = float(fracsec)
timestr_has_fractional_digits = True
for _, strptime_fmt_or_regex, _ in subfmts:
if isinstance(strptime_fmt_or_regex, str):
subfmt_has_sec = "%S" in strptime_fmt_or_regex
try:
tm = time.strptime(timestr, strptime_fmt_or_regex)
except ValueError:
continue
else:
vals = [getattr(tm, "tm_" + component) for component in components]
else:
tm = re.match(strptime_fmt_or_regex, timestr)
if tm is None:
continue
tm = tm.groupdict()
vals = [
int(tm.get(component, default))
for component, default in zip(components, defaults)
]
subfmt_has_sec = "sec" in tm
# Add fractional seconds if they were in the original time string
# and the subformat has seconds. A time like "2022-08-01.123" will
# never pass this for a format like ISO and will raise a parsing
# exception.
if timestr_has_fractional_digits:
if subfmt_has_sec:
vals[-1] = vals[-1] + fracsec
else:
continue
return vals
else:
raise ValueError(f"Time {timestr} does not match {self.name} format")
[docs] def set_jds(self, val1, val2):
"""Parse the time strings contained in val1 and set jd1, jd2"""
# If specific input subformat is required then use the Python parser.
# Also do this if Time format class does not define `use_fast_parser` or
# if the fast parser is entirely disabled. Note that `use_fast_parser`
# is ignored for format classes that don't have a fast parser.
if (
self.in_subfmt != "*"
or "_fast_parser" not in self.__class__.__dict__
or conf.use_fast_parser == "False"
):
jd1, jd2 = self.get_jds_python(val1, val2)
else:
try:
jd1, jd2 = self.get_jds_fast(val1, val2)
except Exception:
# Fall through to the Python parser unless fast is forced.
if conf.use_fast_parser == "force":
raise
else:
jd1, jd2 = self.get_jds_python(val1, val2)
self.jd1 = jd1
self.jd2 = jd2
[docs] def get_jds_python(self, val1, val2):
"""Parse the time strings contained in val1 and get jd1, jd2"""
# Select subformats based on current self.in_subfmt
subfmts = self._select_subfmts(self.in_subfmt)
# Be liberal in what we accept: convert bytes to ascii.
# Here .item() is needed for arrays with entries of unequal length,
# to strip trailing 0 bytes.
to_string = (
str if val1.dtype.kind == "U" else lambda x: str(x.item(), encoding="ascii")
)
iterator = np.nditer(
[val1, None, None, None, None, None, None],
flags=["zerosize_ok"],
op_dtypes=[None] + 5 * [np.intc] + [np.double],
)
for val, iy, im, id, ihr, imin, dsec in iterator:
val = to_string(val)
(
iy[...],
im[...],
id[...],
ihr[...],
imin[...],
dsec[...],
) = self.parse_string(val, subfmts)
jd1, jd2 = erfa.dtf2d(
self.scale.upper().encode("ascii"), *iterator.operands[1:]
)
jd1, jd2 = day_frac(jd1, jd2)
return jd1, jd2
[docs] def get_jds_fast(self, val1, val2):
"""Use fast C parser to parse time strings in val1 and get jd1, jd2"""
# Handle bytes or str input and convert to uint8. We need to the
# dtype _parse_times.dt_u1 instead of uint8, since otherwise it is
# not possible to create a gufunc with structured dtype output.
# See note about ufunc type resolver in pyerfa/erfa/ufunc.c.templ.
if val1.dtype.kind == "U":
# Note: val1.astype('S') is *very* slow, so we check ourselves
# that the input is pure ASCII.
val1_uint32 = val1.view((np.uint32, val1.dtype.itemsize // 4))
if np.any(val1_uint32 > 127):
raise ValueError("input is not pure ASCII")
# It might be possible to avoid making a copy via astype with
# cleverness in parse_times.c but leave that for another day.
chars = val1_uint32.astype(_parse_times.dt_u1)
else:
chars = val1.view((_parse_times.dt_u1, val1.dtype.itemsize))
# Call the fast parsing ufunc.
time_struct = self._fast_parser(chars)
jd1, jd2 = erfa.dtf2d(
self.scale.upper().encode("ascii"),
time_struct["year"],
time_struct["month"],
time_struct["day"],
time_struct["hour"],
time_struct["minute"],
time_struct["second"],
)
return day_frac(jd1, jd2)
[docs] def str_kwargs(self):
"""
Generator that yields a dict of values corresponding to the
calendar date and time for the internal JD values.
"""
scale = (self.scale.upper().encode("ascii"),)
iys, ims, ids, ihmsfs = erfa.d2dtf(
scale, self.precision, self.jd1, self.jd2_filled
)
# Get the str_fmt element of the first allowed output subformat
_, _, str_fmt = self._select_subfmts(self.out_subfmt)[0]
yday = None
has_yday = "{yday:" in str_fmt
ihrs = ihmsfs["h"]
imins = ihmsfs["m"]
isecs = ihmsfs["s"]
ifracs = ihmsfs["f"]
for iy, im, id, ihr, imin, isec, ifracsec in np.nditer(
[iys, ims, ids, ihrs, imins, isecs, ifracs], flags=["zerosize_ok"]
):
if has_yday:
yday = datetime.datetime(iy, im, id).timetuple().tm_yday
yield {
"year": int(iy),
"mon": int(im),
"day": int(id),
"hour": int(ihr),
"min": int(imin),
"sec": int(isec),
"fracsec": int(ifracsec),
"yday": yday,
}
@property
def value(self):
# Select the first available subformat based on current
# self.out_subfmt
subfmts = self._select_subfmts(self.out_subfmt)
_, _, str_fmt = subfmts[0]
# TODO: fix this ugly hack
if self.precision > 0 and str_fmt.endswith("{sec:02d}"):
str_fmt += ".{fracsec:0" + str(self.precision) + "d}"
# Try to optimize this later. Can't pre-allocate because length of
# output could change, e.g. year rolls from 999 to 1000.
outs = []
for kwargs in self.str_kwargs():
outs.append(str(self.format_string(str_fmt, **kwargs)))
return np.array(outs).reshape(self.jd1.shape)
[docs]class TimeISO(TimeString):
"""
ISO 8601 compliant date-time format "YYYY-MM-DD HH:MM:SS.sss...".
For example, 2000-01-01 00:00:00.000 is midnight on January 1, 2000.
The allowed subformats are:
- 'date_hms': date + hours, mins, secs (and optional fractional secs)
- 'date_hm': date + hours, mins
- 'date': date
"""
name = "iso"
subfmts = (
(
"date_hms",
"%Y-%m-%d %H:%M:%S",
# XXX To Do - use strftime for output ??
"{year:d}-{mon:02d}-{day:02d} {hour:02d}:{min:02d}:{sec:02d}",
),
(
"date_hm",
"%Y-%m-%d %H:%M",
"{year:d}-{mon:02d}-{day:02d} {hour:02d}:{min:02d}",
),
("date", "%Y-%m-%d", "{year:d}-{mon:02d}-{day:02d}"),
)
# Define positions and starting delimiter for year, month, day, hour,
# minute, seconds components of an ISO time. This is used by the fast
# C-parser parse_ymdhms_times()
#
# "2000-01-12 13:14:15.678"
# 01234567890123456789012
# yyyy-mm-dd hh:mm:ss.fff
# Parsed as ('yyyy', '-mm', '-dd', ' hh', ':mm', ':ss', '.fff')
fast_parser_pars = dict(
delims=(0, ord("-"), ord("-"), ord(" "), ord(":"), ord(":"), ord(".")),
starts=(0, 4, 7, 10, 13, 16, 19),
stops=(3, 6, 9, 12, 15, 18, -1),
# Break allowed *before*
# y m d h m s f
break_allowed=(0, 0, 0, 1, 0, 1, 1),
has_day_of_year=0,
)
[docs] def parse_string(self, timestr, subfmts):
# Handle trailing 'Z' for UTC time
if timestr.endswith("Z"):
if self.scale != "utc":
raise ValueError("Time input terminating in 'Z' must have scale='UTC'")
timestr = timestr[:-1]
return super().parse_string(timestr, subfmts)
[docs]class TimeISOT(TimeISO):
"""
ISO 8601 compliant date-time format "YYYY-MM-DDTHH:MM:SS.sss...".
This is the same as TimeISO except for a "T" instead of space between
the date and time.
For example, 2000-01-01T00:00:00.000 is midnight on January 1, 2000.
The allowed subformats are:
- 'date_hms': date + hours, mins, secs (and optional fractional secs)
- 'date_hm': date + hours, mins
- 'date': date
"""
name = "isot"
subfmts = (
(
"date_hms",
"%Y-%m-%dT%H:%M:%S",
"{year:d}-{mon:02d}-{day:02d}T{hour:02d}:{min:02d}:{sec:02d}",
),
(
"date_hm",
"%Y-%m-%dT%H:%M",
"{year:d}-{mon:02d}-{day:02d}T{hour:02d}:{min:02d}",
),
("date", "%Y-%m-%d", "{year:d}-{mon:02d}-{day:02d}"),
)
# See TimeISO for explanation
fast_parser_pars = dict(
delims=(0, ord("-"), ord("-"), ord("T"), ord(":"), ord(":"), ord(".")),
starts=(0, 4, 7, 10, 13, 16, 19),
stops=(3, 6, 9, 12, 15, 18, -1),
# Break allowed *before*
# y m d h m s f
break_allowed=(0, 0, 0, 1, 0, 1, 1),
has_day_of_year=0,
)
[docs]class TimeYearDayTime(TimeISO):
"""
Year, day-of-year and time as "YYYY:DOY:HH:MM:SS.sss...".
The day-of-year (DOY) goes from 001 to 365 (366 in leap years).
For example, 2000:001:00:00:00.000 is midnight on January 1, 2000.
The allowed subformats are:
- 'date_hms': date + hours, mins, secs (and optional fractional secs)
- 'date_hm': date + hours, mins
- 'date': date
"""
name = "yday"
subfmts = (
(
"date_hms",
"%Y:%j:%H:%M:%S",
"{year:d}:{yday:03d}:{hour:02d}:{min:02d}:{sec:02d}",
),
("date_hm", "%Y:%j:%H:%M", "{year:d}:{yday:03d}:{hour:02d}:{min:02d}"),
("date", "%Y:%j", "{year:d}:{yday:03d}"),
)
# Define positions and starting delimiter for year, month, day, hour,
# minute, seconds components of an ISO time. This is used by the fast
# C-parser parse_ymdhms_times()
#
# "2000:123:13:14:15.678"
# 012345678901234567890
# yyyy:ddd:hh:mm:ss.fff
# Parsed as ('yyyy', ':ddd', ':hh', ':mm', ':ss', '.fff')
#
# delims: character at corresponding `starts` position (0 => no character)
# starts: position where component starts (including delimiter if present)
# stops: position where component ends (-1 => continue to end of string)
fast_parser_pars = dict(
delims=(0, 0, ord(":"), ord(":"), ord(":"), ord(":"), ord(".")),
starts=(0, -1, 4, 8, 11, 14, 17),
stops=(3, -1, 7, 10, 13, 16, -1),
# Break allowed before:
# y m d h m s f
break_allowed=(0, 0, 0, 1, 0, 1, 1),
has_day_of_year=1,
)
[docs]class TimeDatetime64(TimeISOT):
name = "datetime64"
def _check_val_type(self, val1, val2):
if not val1.dtype.kind == "M":
if val1.size > 0:
raise TypeError(
f"Input values for {self.name} class must be datetime64 objects"
)
else:
val1 = np.array([], "datetime64[D]")
if val2 is not None:
raise ValueError(
f"{self.name} objects do not accept a val2 but you provided {val2}"
)
return val1, None
[docs] def set_jds(self, val1, val2):
# If there are any masked values in the ``val1`` datetime64 array
# ('NaT') then stub them with a valid date so downstream parse_string
# will work. The value under the mask is arbitrary but a "modern" date
# is good.
mask = np.isnat(val1)
masked = np.any(mask)
if masked:
val1 = val1.copy()
val1[mask] = "2000"
# Make sure M(onth) and Y(ear) dates will parse and convert to bytestring
if val1.dtype.name in ["datetime64[M]", "datetime64[Y]"]:
val1 = val1.astype("datetime64[D]")
val1 = val1.astype("S")
# Standard ISO string parsing now
super().set_jds(val1, val2)
# Finally apply mask if necessary
if masked:
self.jd2[mask] = np.nan
@property
def value(self):
precision = self.precision
self.precision = 9
ret = super().value
self.precision = precision
return ret.astype("datetime64")
[docs]class TimeFITS(TimeString):
"""
FITS format: "[±Y]YYYY-MM-DD[THH:MM:SS[.sss]]".
ISOT but can give signed five-digit year (mostly for negative years);
The allowed subformats are:
- 'date_hms': date + hours, mins, secs (and optional fractional secs)
- 'date': date
- 'longdate_hms': as 'date_hms', but with signed 5-digit year
- 'longdate': as 'date', but with signed 5-digit year
See Rots et al., 2015, A&A 574:A36 (arXiv:1409.7583).
"""
name = "fits"
subfmts = (
(
"date_hms",
(
r"(?P<year>\d{4})-(?P<mon>\d\d)-(?P<mday>\d\d)T"
r"(?P<hour>\d\d):(?P<min>\d\d):(?P<sec>\d\d(\.\d*)?)"
),
"{year:04d}-{mon:02d}-{day:02d}T{hour:02d}:{min:02d}:{sec:02d}",
),
(
"date",
r"(?P<year>\d{4})-(?P<mon>\d\d)-(?P<mday>\d\d)",
"{year:04d}-{mon:02d}-{day:02d}",
),
(
"longdate_hms",
(
r"(?P<year>[+-]\d{5})-(?P<mon>\d\d)-(?P<mday>\d\d)T"
r"(?P<hour>\d\d):(?P<min>\d\d):(?P<sec>\d\d(\.\d*)?)"
),
"{year:+06d}-{mon:02d}-{day:02d}T{hour:02d}:{min:02d}:{sec:02d}",
),
(
"longdate",
r"(?P<year>[+-]\d{5})-(?P<mon>\d\d)-(?P<mday>\d\d)",
"{year:+06d}-{mon:02d}-{day:02d}",
),
)
# Add the regex that parses the scale and possible realization.
# Support for this is deprecated. Read old style but no longer write
# in this style.
subfmts = tuple(
(
subfmt[0],
subfmt[1] + r"(\((?P<scale>\w+)(\((?P<realization>\w+)\))?\))?",
subfmt[2],
)
for subfmt in subfmts
)
[docs] def parse_string(self, timestr, subfmts):
"""Read time and deprecated scale if present"""
# Try parsing with any of the allowed sub-formats.
for _, regex, _ in subfmts:
tm = re.match(regex, timestr)
if tm:
break
else:
raise ValueError(f"Time {timestr} does not match {self.name} format")
tm = tm.groupdict()
# Scale and realization are deprecated and strings in this form
# are no longer created. We issue a warning but still use the value.
if tm["scale"] is not None:
warnings.warn(
"FITS time strings should no longer have embedded time scale.",
AstropyDeprecationWarning,
)
# If a scale was given, translate from a possible deprecated
# timescale identifier to the scale used by Time.
fits_scale = tm["scale"].upper()
scale = FITS_DEPRECATED_SCALES.get(fits_scale, fits_scale.lower())
if scale not in TIME_SCALES:
raise ValueError(
f"Scale {scale!r} is not in the allowed scales "
f"{sorted(TIME_SCALES)}"
)
# If no scale was given in the initialiser, set the scale to
# that given in the string. Realization is ignored
# and is only supported to allow old-style strings to be
# parsed.
if self._scale is None:
self._scale = scale
if scale != self.scale:
raise ValueError(
f"Input strings for {self.name} class must all "
"have consistent time scales."
)
return [
int(tm["year"]),
int(tm["mon"]),
int(tm["mday"]),
int(tm.get("hour", 0)),
int(tm.get("min", 0)),
float(tm.get("sec", 0.0)),
]
@property
def value(self):
"""Convert times to strings, using signed 5 digit if necessary."""
if "long" not in self.out_subfmt:
# If we have times before year 0 or after year 9999, we can
# output only in a "long" format, using signed 5-digit years.
jd = self.jd1 + self.jd2
if jd.size and (jd.min() < 1721425.5 or jd.max() >= 5373484.5):
self.out_subfmt = "long" + self.out_subfmt
return super().value
[docs]class TimeEpochDate(TimeNumeric):
"""
Base class for support floating point Besselian and Julian epoch dates
"""
_default_scale = "tt" # As of astropy 3.2, this is no longer 'utc'.
[docs] def set_jds(self, val1, val2):
self._check_scale(self._scale) # validate scale.
epoch_to_jd = getattr(erfa, self.epoch_to_jd)
jd1, jd2 = epoch_to_jd(val1 + val2)
self.jd1, self.jd2 = day_frac(jd1, jd2)
[docs] def to_value(self, **kwargs):
jd_to_epoch = getattr(erfa, self.jd_to_epoch)
value = jd_to_epoch(self.jd1, self.jd2)
return super().to_value(jd1=value, jd2=np.float64(0.0), **kwargs)
value = property(to_value)
[docs]class TimeBesselianEpoch(TimeEpochDate):
"""Besselian Epoch year as floating point value(s) like 1950.0"""
name = "byear"
epoch_to_jd = "epb2jd"
jd_to_epoch = "epb"
def _check_val_type(self, val1, val2):
"""Input value validation, typically overridden by derived classes"""
if hasattr(val1, "to") and hasattr(val1, "unit") and val1.unit is not None:
raise ValueError(
"Cannot use Quantities for 'byear' format, as the interpretation "
"would be ambiguous. Use float with Besselian year instead."
)
# FIXME: is val2 really okay here?
return super()._check_val_type(val1, val2)
[docs]class TimeJulianEpoch(TimeEpochDate):
"""Julian Epoch year as floating point value(s) like 2000.0"""
name = "jyear"
unit = erfa.DJY # 365.25, the Julian year, for conversion to quantities
epoch_to_jd = "epj2jd"
jd_to_epoch = "epj"
[docs]class TimeEpochDateString(TimeString):
"""
Base class to support string Besselian and Julian epoch dates
such as 'B1950.0' or 'J2000.0' respectively.
"""
_default_scale = "tt" # As of astropy 3.2, this is no longer 'utc'.
[docs] def set_jds(self, val1, val2):
epoch_prefix = self.epoch_prefix
# Be liberal in what we accept: convert bytes to ascii.
to_string = (
str if val1.dtype.kind == "U" else lambda x: str(x.item(), encoding="ascii")
)
iterator = np.nditer(
[val1, None], op_dtypes=[val1.dtype, np.double], flags=["zerosize_ok"]
)
for val, years in iterator:
try:
time_str = to_string(val)
epoch_type, year_str = time_str[0], time_str[1:]
year = float(year_str)
if epoch_type.upper() != epoch_prefix:
raise ValueError
except (IndexError, ValueError, UnicodeEncodeError):
raise ValueError(f"Time {val} does not match {self.name} format")
else:
years[...] = year
self._check_scale(self._scale) # validate scale.
epoch_to_jd = getattr(erfa, self.epoch_to_jd)
jd1, jd2 = epoch_to_jd(iterator.operands[-1])
self.jd1, self.jd2 = day_frac(jd1, jd2)
@property
def value(self):
jd_to_epoch = getattr(erfa, self.jd_to_epoch)
years = jd_to_epoch(self.jd1, self.jd2)
# Use old-style format since it is a factor of 2 faster
str_fmt = self.epoch_prefix + "%." + str(self.precision) + "f"
outs = [str_fmt % year for year in years.flat]
return np.array(outs).reshape(self.jd1.shape)
[docs]class TimeBesselianEpochString(TimeEpochDateString):
"""Besselian Epoch year as string value(s) like 'B1950.0'"""
name = "byear_str"
epoch_to_jd = "epb2jd"
jd_to_epoch = "epb"
epoch_prefix = "B"
[docs]class TimeJulianEpochString(TimeEpochDateString):
"""Julian Epoch year as string value(s) like 'J2000.0'"""
name = "jyear_str"
epoch_to_jd = "epj2jd"
jd_to_epoch = "epj"
epoch_prefix = "J"
[docs]class TimeDeltaNumeric(TimeDeltaFormat, TimeNumeric):
[docs] def set_jds(self, val1, val2):
self._check_scale(self._scale) # Validate scale.
self.jd1, self.jd2 = day_frac(val1, val2, divisor=1.0 / self.unit)
[docs] def to_value(self, **kwargs):
# Note that 1/unit is always exactly representable, so the
# following multiplications are exact.
factor = 1.0 / self.unit
jd1 = self.jd1 * factor
jd2 = self.jd2 * factor
return super().to_value(jd1=jd1, jd2=jd2, **kwargs)
value = property(to_value)
[docs]class TimeDeltaSec(TimeDeltaNumeric):
"""Time delta in SI seconds"""
name = "sec"
unit = 1.0 / erfa.DAYSEC # for quantity input
[docs]class TimeDeltaJD(TimeDeltaNumeric):
"""Time delta in Julian days (86400 SI seconds)"""
name = "jd"
unit = 1.0
[docs]class TimeDeltaDatetime(TimeDeltaFormat, TimeUnique):
"""Time delta in datetime.timedelta"""
name = "datetime"
def _check_val_type(self, val1, val2):
if not all(isinstance(val, datetime.timedelta) for val in val1.flat):
raise TypeError(
f"Input values for {self.name} class must be datetime.timedelta objects"
)
if val2 is not None:
raise ValueError(
f"{self.name} objects do not accept a val2 but you provided {val2}"
)
return val1, None
[docs] def set_jds(self, val1, val2):
self._check_scale(self._scale) # Validate scale.
iterator = np.nditer(
[val1, None, None],
flags=["refs_ok", "zerosize_ok"],
op_dtypes=[None, np.double, np.double],
)
day = datetime.timedelta(days=1)
for val, jd1, jd2 in iterator:
jd1[...], other = divmod(val.item(), day)
jd2[...] = other / day
self.jd1, self.jd2 = day_frac(iterator.operands[-2], iterator.operands[-1])
@property
def value(self):
iterator = np.nditer(
[self.jd1, self.jd2, None],
flags=["refs_ok", "zerosize_ok"],
op_dtypes=[None, None, object],
)
for jd1, jd2, out in iterator:
jd1_, jd2_ = day_frac(jd1, jd2)
out[...] = datetime.timedelta(days=jd1_, microseconds=jd2_ * 86400 * 1e6)
return self.mask_if_needed(iterator.operands[-1])
def _validate_jd_for_storage(jd):
if isinstance(jd, (float, int)):
return np.array(jd, dtype=np.float_)
if isinstance(jd, np.generic) and (
jd.dtype.kind == "f" and jd.dtype.itemsize <= 8 or jd.dtype.kind in "iu"
):
return np.array(jd, dtype=np.float_)
elif isinstance(jd, np.ndarray) and jd.dtype.kind == "f" and jd.dtype.itemsize == 8:
return jd
else:
raise TypeError(
"JD values must be arrays (possibly zero-dimensional) "
f"of floats but we got {jd!r} of type {type(jd)}"
)
def _broadcast_writeable(jd1, jd2):
if jd1.shape == jd2.shape:
return jd1, jd2
# When using broadcast_arrays, *both* are flagged with
# warn-on-write, even the one that wasn't modified, and
# require "C" only clears the flag if it actually copied
# anything.
shape = np.broadcast(jd1, jd2).shape
if jd1.shape == shape:
s_jd1 = jd1
else:
s_jd1 = np.require(np.broadcast_to(jd1, shape), requirements=["C", "W"])
if jd2.shape == shape:
s_jd2 = jd2
else:
s_jd2 = np.require(np.broadcast_to(jd2, shape), requirements=["C", "W"])
return s_jd1, s_jd2
# Import symbols from core.py that are used in this module. This succeeds
# because __init__.py imports format.py just before core.py.
from .core import TIME_DELTA_SCALES, TIME_SCALES, ScaleValueError, Time # noqa: E402