Inzynierka/Lib/site-packages/pandas/_libs/tslib.pyx

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2023-06-02 12:51:02 +02:00
import warnings
from pandas.util._exceptions import find_stack_level
cimport cython
from datetime import timezone
from cpython.datetime cimport (
PyDate_Check,
PyDateTime_Check,
datetime,
import_datetime,
timedelta,
tzinfo,
)
from cpython.object cimport PyObject
# import datetime C API
import_datetime()
cimport numpy as cnp
from numpy cimport (
int64_t,
ndarray,
)
import numpy as np
cnp.import_array()
from pandas._libs.tslibs.np_datetime cimport (
NPY_DATETIMEUNIT,
NPY_FR_ns,
check_dts_bounds,
npy_datetimestruct,
npy_datetimestruct_to_datetime,
pandas_datetime_to_datetimestruct,
pydate_to_dt64,
string_to_dts,
)
from pandas._libs.tslibs.strptime cimport parse_today_now
from pandas._libs.util cimport (
is_datetime64_object,
is_float_object,
is_integer_object,
)
from pandas._libs.tslibs.np_datetime import OutOfBoundsDatetime
from pandas._libs.tslibs.conversion cimport (
_TSObject,
cast_from_unit,
convert_str_to_tsobject,
convert_timezone,
get_datetime64_nanos,
parse_pydatetime,
precision_from_unit,
)
from pandas._libs.tslibs.nattype cimport (
NPY_NAT,
c_NaT as NaT,
c_nat_strings as nat_strings,
)
from pandas._libs.tslibs.timestamps cimport _Timestamp
from pandas._libs.tslibs import (
Resolution,
get_resolution,
)
from pandas._libs.tslibs.timestamps import Timestamp
# Note: this is the only non-tslibs intra-pandas dependency here
from pandas._libs.missing cimport checknull_with_nat_and_na
from pandas._libs.tslibs.tzconversion cimport tz_localize_to_utc_single
def _test_parse_iso8601(ts: str):
"""
TESTING ONLY: Parse string into Timestamp using iso8601 parser. Used
only for testing, actual construction uses `convert_str_to_tsobject`
"""
cdef:
_TSObject obj
int out_local = 0, out_tzoffset = 0
NPY_DATETIMEUNIT out_bestunit
obj = _TSObject()
string_to_dts(ts, &obj.dts, &out_bestunit, &out_local, &out_tzoffset, True)
obj.value = npy_datetimestruct_to_datetime(NPY_FR_ns, &obj.dts)
check_dts_bounds(&obj.dts)
if out_local == 1:
obj.tzinfo = timezone(timedelta(minutes=out_tzoffset))
obj.value = tz_localize_to_utc_single(obj.value, obj.tzinfo)
return Timestamp(obj.value, tz=obj.tzinfo)
else:
return Timestamp(obj.value)
@cython.wraparound(False)
@cython.boundscheck(False)
def format_array_from_datetime(
ndarray values,
tzinfo tz=None,
str format=None,
na_rep: str | float = "NaT",
NPY_DATETIMEUNIT reso=NPY_FR_ns,
) -> np.ndarray:
"""
return a np object array of the string formatted values
Parameters
----------
values : ndarray[int64_t], arbitrary ndim
tz : tzinfo or None, default None
format : str or None, default None
a strftime capable string
na_rep : optional, default is None
a nat format
reso : NPY_DATETIMEUNIT, default NPY_FR_ns
Returns
-------
np.ndarray[object]
"""
cdef:
int64_t val, ns, N = values.size
bint show_ms = False, show_us = False, show_ns = False
bint basic_format = False, basic_format_day = False
_Timestamp ts
object res
npy_datetimestruct dts
# Note that `result` (and thus `result_flat`) is C-order and
# `it` iterates C-order as well, so the iteration matches
# See discussion at
# github.com/pandas-dev/pandas/pull/46886#discussion_r860261305
ndarray result = cnp.PyArray_EMPTY(values.ndim, values.shape, cnp.NPY_OBJECT, 0)
object[::1] res_flat = result.ravel() # should NOT be a copy
cnp.flatiter it = cnp.PyArray_IterNew(values)
if tz is None:
# if we don't have a format nor tz, then choose
# a format based on precision
basic_format = format is None
if basic_format:
reso_obj = get_resolution(values, tz=tz, reso=reso)
show_ns = reso_obj == Resolution.RESO_NS
show_us = reso_obj == Resolution.RESO_US
show_ms = reso_obj == Resolution.RESO_MS
elif format == "%Y-%m-%d %H:%M:%S":
# Same format as default, but with hardcoded precision (s)
basic_format = True
show_ns = show_us = show_ms = False
elif format == "%Y-%m-%d %H:%M:%S.%f":
# Same format as default, but with hardcoded precision (us)
basic_format = show_us = True
show_ns = show_ms = False
elif format == "%Y-%m-%d":
# Default format for dates
basic_format_day = True
assert not (basic_format_day and basic_format)
for i in range(N):
# Analogous to: utc_val = values[i]
val = (<int64_t*>cnp.PyArray_ITER_DATA(it))[0]
if val == NPY_NAT:
res = na_rep
elif basic_format_day:
pandas_datetime_to_datetimestruct(val, reso, &dts)
res = f"{dts.year}-{dts.month:02d}-{dts.day:02d}"
elif basic_format:
pandas_datetime_to_datetimestruct(val, reso, &dts)
res = (f"{dts.year}-{dts.month:02d}-{dts.day:02d} "
f"{dts.hour:02d}:{dts.min:02d}:{dts.sec:02d}")
if show_ns:
ns = dts.ps // 1000
res += f".{ns + dts.us * 1000:09d}"
elif show_us:
res += f".{dts.us:06d}"
elif show_ms:
res += f".{dts.us // 1000:03d}"
else:
ts = Timestamp._from_value_and_reso(val, reso=reso, tz=tz)
if format is None:
# Use datetime.str, that returns ts.isoformat(sep=' ')
res = str(ts)
else:
# invalid format string
# requires dates > 1900
try:
# Note: dispatches to pydatetime
res = ts.strftime(format)
except ValueError:
# Use datetime.str, that returns ts.isoformat(sep=' ')
res = str(ts)
# Note: we can index result directly instead of using PyArray_MultiIter_DATA
# like we do for the other functions because result is known C-contiguous
# and is the first argument to PyArray_MultiIterNew2. The usual pattern
# does not seem to work with object dtype.
# See discussion at
# github.com/pandas-dev/pandas/pull/46886#discussion_r860261305
res_flat[i] = res
cnp.PyArray_ITER_NEXT(it)
return result
def array_with_unit_to_datetime(
ndarray[object] values,
str unit,
str errors="coerce"
):
"""
Convert the ndarray to datetime according to the time unit.
This function converts an array of objects into a numpy array of
datetime64[ns]. It returns the converted array
and also returns the timezone offset
if errors:
- raise: return converted values or raise OutOfBoundsDatetime
if out of range on the conversion or
ValueError for other conversions (e.g. a string)
- ignore: return non-convertible values as the same unit
- coerce: NaT for non-convertibles
Parameters
----------
values : ndarray
Date-like objects to convert.
unit : str
Time unit to use during conversion.
errors : str, default 'raise'
Error behavior when parsing.
Returns
-------
result : ndarray of m8 values
tz : parsed timezone offset or None
"""
cdef:
Py_ssize_t i, n=len(values)
int64_t mult
bint is_ignore = errors == "ignore"
bint is_coerce = errors == "coerce"
bint is_raise = errors == "raise"
ndarray[int64_t] iresult
tzinfo tz = None
float fval
assert is_ignore or is_coerce or is_raise
if unit == "ns":
result, tz = array_to_datetime(
values.astype(object, copy=False),
errors=errors,
)
return result, tz
mult, _ = precision_from_unit(unit)
result = np.empty(n, dtype="M8[ns]")
iresult = result.view("i8")
for i in range(n):
val = values[i]
try:
if checknull_with_nat_and_na(val):
iresult[i] = NPY_NAT
elif is_integer_object(val) or is_float_object(val):
if val != val or val == NPY_NAT:
iresult[i] = NPY_NAT
else:
iresult[i] = cast_from_unit(val, unit)
elif isinstance(val, str):
if len(val) == 0 or val in nat_strings:
iresult[i] = NPY_NAT
else:
try:
fval = float(val)
except ValueError:
raise ValueError(
f"non convertible value {val} with the unit '{unit}'"
)
warnings.warn(
"The behavior of 'to_datetime' with 'unit' when parsing "
"strings is deprecated. In a future version, strings will "
"be parsed as datetime strings, matching the behavior "
"without a 'unit'. To retain the old behavior, explicitly "
"cast ints or floats to numeric type before calling "
"to_datetime.",
FutureWarning,
stacklevel=find_stack_level(),
)
iresult[i] = cast_from_unit(fval, unit)
else:
# TODO: makes more sense as TypeError, but that would be an
# API change.
raise ValueError(
f"unit='{unit}' not valid with non-numerical val='{val}'"
)
except (ValueError, OutOfBoundsDatetime, TypeError) as err:
if is_raise:
err.args = (f"{err}, at position {i}",)
raise
elif is_ignore:
# we have hit an exception
# and are in ignore mode
# redo as object
return _array_with_unit_to_datetime_object_fallback(values, unit)
else:
# is_coerce
iresult[i] = NPY_NAT
return result, tz
cdef _array_with_unit_to_datetime_object_fallback(ndarray[object] values, str unit):
cdef:
Py_ssize_t i, n = len(values)
ndarray[object] oresult
tzinfo tz = None
# TODO: fix subtle differences between this and no-unit code
oresult = cnp.PyArray_EMPTY(values.ndim, values.shape, cnp.NPY_OBJECT, 0)
for i in range(n):
val = values[i]
if checknull_with_nat_and_na(val):
oresult[i] = <object>NaT
elif is_integer_object(val) or is_float_object(val):
if val != val or val == NPY_NAT:
oresult[i] = <object>NaT
else:
try:
oresult[i] = Timestamp(val, unit=unit)
except OutOfBoundsDatetime:
oresult[i] = val
elif isinstance(val, str):
if len(val) == 0 or val in nat_strings:
oresult[i] = <object>NaT
else:
oresult[i] = val
return oresult, tz
@cython.wraparound(False)
@cython.boundscheck(False)
def first_non_null(values: ndarray) -> int:
"""Find position of first non-null value, return -1 if there isn't one."""
cdef:
Py_ssize_t n = len(values)
Py_ssize_t i
for i in range(n):
val = values[i]
if checknull_with_nat_and_na(val):
continue
if (
isinstance(val, str)
and
(len(val) == 0 or val in nat_strings or val in ("now", "today"))
):
continue
return i
else:
return -1
@cython.wraparound(False)
@cython.boundscheck(False)
cpdef array_to_datetime(
ndarray values, # object dtype, arbitrary ndim
str errors="raise",
bint dayfirst=False,
bint yearfirst=False,
bint utc=False,
):
"""
Converts a 1D array of date-like values to a numpy array of either:
1) datetime64[ns] data
2) datetime.datetime objects, if OutOfBoundsDatetime or TypeError
is encountered
Also returns a fixed-offset tzinfo object if an array of strings with the same
timezone offset is passed and utc=True is not passed. Otherwise, None
is returned
Handles datetime.date, datetime.datetime, np.datetime64 objects, numeric,
strings
Parameters
----------
values : ndarray of object
date-like objects to convert
errors : str, default 'raise'
error behavior when parsing
dayfirst : bool, default False
dayfirst parsing behavior when encountering datetime strings
yearfirst : bool, default False
yearfirst parsing behavior when encountering datetime strings
utc : bool, default False
indicator whether the dates should be UTC
Returns
-------
np.ndarray
May be datetime64[ns] or object dtype
tzinfo or None
"""
cdef:
Py_ssize_t i, n = values.size
object val, tz
ndarray[int64_t] iresult
npy_datetimestruct dts
bint utc_convert = bool(utc)
bint seen_datetime_offset = False
bint is_raise = errors == "raise"
bint is_ignore = errors == "ignore"
bint is_coerce = errors == "coerce"
bint is_same_offsets
_TSObject _ts
float tz_offset
set out_tzoffset_vals = set()
tzinfo tz_out = None
bint found_tz = False, found_naive = False
cnp.broadcast mi
# specify error conditions
assert is_raise or is_ignore or is_coerce
result = np.empty((<object>values).shape, dtype="M8[ns]")
mi = cnp.PyArray_MultiIterNew2(result, values)
iresult = result.view("i8").ravel()
for i in range(n):
# Analogous to `val = values[i]`
val = <object>(<PyObject**>cnp.PyArray_MultiIter_DATA(mi, 1))[0]
try:
if checknull_with_nat_and_na(val):
iresult[i] = NPY_NAT
elif PyDateTime_Check(val):
if val.tzinfo is not None:
found_tz = True
else:
found_naive = True
tz_out = convert_timezone(
val.tzinfo,
tz_out,
found_naive,
found_tz,
utc_convert,
)
iresult[i] = parse_pydatetime(val, &dts, utc_convert)
elif PyDate_Check(val):
iresult[i] = pydate_to_dt64(val, &dts)
check_dts_bounds(&dts)
elif is_datetime64_object(val):
iresult[i] = get_datetime64_nanos(val, NPY_FR_ns)
elif is_integer_object(val) or is_float_object(val):
# these must be ns unit by-definition
if val != val or val == NPY_NAT:
iresult[i] = NPY_NAT
else:
# we now need to parse this as if unit='ns'
iresult[i] = cast_from_unit(val, "ns")
elif isinstance(val, str):
# string
if type(val) is not str:
# GH#32264 np.str_ object
val = str(val)
if parse_today_now(val, &iresult[i], utc):
# We can't _quite_ dispatch this to convert_str_to_tsobject
# bc there isn't a nice way to pass "utc"
cnp.PyArray_MultiIter_NEXT(mi)
continue
_ts = convert_str_to_tsobject(
val, None, unit="ns", dayfirst=dayfirst, yearfirst=yearfirst
)
_ts.ensure_reso(NPY_FR_ns, val)
iresult[i] = _ts.value
tz = _ts.tzinfo
if tz is not None:
# dateutil timezone objects cannot be hashed, so
# store the UTC offsets in seconds instead
nsecs = tz.utcoffset(None).total_seconds()
out_tzoffset_vals.add(nsecs)
# need to set seen_datetime_offset *after* the
# potentially-raising timezone(timedelta(...)) call,
# otherwise we can go down the is_same_offsets path
# bc len(out_tzoffset_vals) == 0
seen_datetime_offset = True
else:
# Add a marker for naive string, to track if we are
# parsing mixed naive and aware strings
out_tzoffset_vals.add("naive")
else:
raise TypeError(f"{type(val)} is not convertible to datetime")
cnp.PyArray_MultiIter_NEXT(mi)
except (TypeError, OverflowError, ValueError) as ex:
ex.args = (f"{ex}, at position {i}",)
if is_coerce:
iresult[i] = NPY_NAT
cnp.PyArray_MultiIter_NEXT(mi)
continue
elif is_raise:
raise
return values, None
if seen_datetime_offset and not utc_convert:
# GH#17697
# 1) If all the offsets are equal, return one offset for
# the parsed dates to (maybe) pass to DatetimeIndex
# 2) If the offsets are different, then force the parsing down the
# object path where an array of datetimes
# (with individual dateutil.tzoffsets) are returned
is_same_offsets = len(out_tzoffset_vals) == 1
if not is_same_offsets:
return _array_to_datetime_object(values, errors, dayfirst, yearfirst)
else:
tz_offset = out_tzoffset_vals.pop()
tz_out = timezone(timedelta(seconds=tz_offset))
return result, tz_out
@cython.wraparound(False)
@cython.boundscheck(False)
cdef _array_to_datetime_object(
ndarray[object] values,
str errors,
bint dayfirst=False,
bint yearfirst=False,
):
"""
Fall back function for array_to_datetime
Attempts to parse datetime strings with dateutil to return an array
of datetime objects
Parameters
----------
values : ndarray[object]
date-like objects to convert
errors : str
error behavior when parsing
dayfirst : bool, default False
dayfirst parsing behavior when encountering datetime strings
yearfirst : bool, default False
yearfirst parsing behavior when encountering datetime strings
Returns
-------
np.ndarray[object]
Literal[None]
"""
cdef:
Py_ssize_t i, n = values.size
object val
bint is_ignore = errors == "ignore"
bint is_coerce = errors == "coerce"
bint is_raise = errors == "raise"
ndarray oresult_nd
ndarray[object] oresult
npy_datetimestruct dts
cnp.broadcast mi
_TSObject tsobj
assert is_raise or is_ignore or is_coerce
oresult_nd = cnp.PyArray_EMPTY(values.ndim, values.shape, cnp.NPY_OBJECT, 0)
mi = cnp.PyArray_MultiIterNew2(oresult_nd, values)
oresult = oresult_nd.ravel()
# We return an object array and only attempt to parse:
# 1) NaT or NaT-like values
# 2) datetime strings, which we return as datetime.datetime
# 3) special strings - "now" & "today"
for i in range(n):
# Analogous to: val = values[i]
val = <object>(<PyObject**>cnp.PyArray_MultiIter_DATA(mi, 1))[0]
if checknull_with_nat_and_na(val) or PyDateTime_Check(val):
# GH 25978. No need to parse NaT-like or datetime-like vals
oresult[i] = val
elif isinstance(val, str):
if type(val) is not str:
# GH#32264 np.str_ objects
val = str(val)
if len(val) == 0 or val in nat_strings:
oresult[i] = "NaT"
cnp.PyArray_MultiIter_NEXT(mi)
continue
try:
tsobj = convert_str_to_tsobject(
val, None, unit="ns", dayfirst=dayfirst, yearfirst=yearfirst
)
tsobj.ensure_reso(NPY_FR_ns, val)
dts = tsobj.dts
oresult[i] = datetime(
dts.year, dts.month, dts.day, dts.hour, dts.min, dts.sec, dts.us,
tzinfo=tsobj.tzinfo,
fold=tsobj.fold,
)
except (ValueError, OverflowError) as ex:
ex.args = (f"{ex}, at position {i}", )
if is_coerce:
oresult[i] = <object>NaT
cnp.PyArray_MultiIter_NEXT(mi)
continue
if is_raise:
raise
return values, None
else:
if is_raise:
raise
return values, None
cnp.PyArray_MultiIter_NEXT(mi)
return oresult_nd, None
def array_to_datetime_with_tz(ndarray values, tzinfo tz):
"""
Vectorized analogue to pd.Timestamp(value, tz=tz)
values has object-dtype, unrestricted ndim.
Major differences between this and array_to_datetime with utc=True
- np.datetime64 objects are treated as _wall_ times.
- tznaive datetimes are treated as _wall_ times.
"""
cdef:
ndarray result = cnp.PyArray_EMPTY(values.ndim, values.shape, cnp.NPY_INT64, 0)
cnp.broadcast mi = cnp.PyArray_MultiIterNew2(result, values)
Py_ssize_t i, n = values.size
object item
int64_t ival
datetime ts
for i in range(n):
# Analogous to `item = values[i]`
item = <object>(<PyObject**>cnp.PyArray_MultiIter_DATA(mi, 1))[0]
if checknull_with_nat_and_na(item):
# this catches pd.NA which would raise in the Timestamp constructor
ival = NPY_NAT
else:
ts = Timestamp(item)
if ts is NaT:
ival = NPY_NAT
else:
if ts.tz is not None:
ts = ts.tz_convert(tz)
else:
# datetime64, tznaive pydatetime, int, float
ts = ts.tz_localize(tz)
ts = ts.as_unit("ns")
ival = ts._value
# Analogous to: result[i] = ival
(<int64_t*>cnp.PyArray_MultiIter_DATA(mi, 0))[0] = ival
cnp.PyArray_MultiIter_NEXT(mi)
return result