NumPyTimeBuilder ================ aniso8601 builder for NumPy datetimes ------------------------------------- Features ======== * Provides :code:`NumPyTimeBuilder` compatible with `aniso8601 `_ * Returns :code:`datetime64` and :code:`timedelta64` `NumPy types `_ Installation ============ The recommended installation method is to use pip:: $ pip install numpytimebuilder Alternatively, you can download the source (git repository hosted at `Codeberg `_) and install directly:: $ python setup.py install Use === Parsing datetimes ----------------- To parse a typical ISO 8601 datetime string:: >>> import aniso8601 >>> from numpytimebuilder import NumPyTimeBuilder >>> aniso8601.parse_datetime('1977-06-10T12:00:00', builder=NumPyTimeBuilder) numpy.datetime64('1977-06-10T12:00:00') Alternative delimiters can be specified, for example, a space:: >>> aniso8601.parse_datetime('1977-06-10 12:00:00', delimiter=' ', builder=NumPyTimeBuilder) numpy.datetime64('1977-06-10T12:00:00') Since the NumPy :code:`datetime64` implementaton only supports naive datetimes, timezones are explicitly not supported:: >>> aniso8601.parse_datetime('1977-06-10T12:00:00Z', builder=NumPyTimeBuilder) Traceback (most recent call last): File "", line 1, in File "/home/nielsenb/Jetfuse/numpytimebuilder/python2/lib/python2.7/site-packages/aniso8601/time.py", line 131, in parse_datetime return builder.build_datetime(datepart, timepart) File "numpytimebuilder/__init__.py", line 37, in build_datetime raise NotImplementedError('Timezones are not supported by numpy ' NotImplementedError: Timezones are not supported by numpy datetime64 type. >>> aniso8601.parse_datetime('1979-06-05T08:00:00-08:00', builder=NumPyTimeBuilder) Traceback (most recent call last): File "", line 1, in File "/home/nielsenb/Jetfuse/numpytimebuilder/python2/lib/python2.7/site-packages/aniso8601/time.py", line 131, in parse_datetime return builder.build_datetime(datepart, timepart) File "numpytimebuilder/__init__.py", line 37, in build_datetime raise NotImplementedError('Timezones are not supported by numpy ' NotImplementedError: Timezones are not supported by numpy datetime64 type Leap seconds are not currently supported by the NumPy :code:`datetime64` implementation, so leap seconds are explicitly not supported:: >>> aniso8601.parse_datetime('2018-03-06T23:59:60', builder=NumPyTimeBuilder) Traceback (most recent call last): File "", line 1, in File "/home/nielsenb/Jetfuse/numpytimebuilder/python2/lib/python2.7/site-packages/aniso8601/time.py", line 131, in parse_datetime return builder.build_datetime(datepart, timepart) File "numpytimebuilder/__init__.py", line 120, in build_datetime raise LeapSecondError('Leap seconds are not supported.') aniso8601.exceptions.LeapSecondError: Leap seconds are not supported. Parsing dates ------------- To parse a date represented in an ISO 8601 string:: >>> import aniso8601 >>> from numpytimebuilder import NumPyTimeBuilder >>> aniso8601.parse_date('1984-04-23', builder=NumPyTimeBuilder) numpy.datetime64('1984-04-23') Basic format is supported as well:: >>> aniso8601.parse_date('19840423', builder=NumPyTimeBuilder) numpy.datetime64('1984-04-23') To parse a date using the ISO 8601 week date format:: >>> aniso8601.parse_date('1986-W38-1', builder=NumPyTimeBuilder) numpy.datetime64('1986-09-15') To parse an ISO 8601 ordinal date:: >>> aniso8601.parse_date('1988-132', builder=NumPyTimeBuilder) numpy.datetime64('1988-05-11') Parsing times ------------- NumPy offers no :code:`time64` type, so parsing times is explicitly not supported:: >>> import aniso8601 >>> from numpytimebuilder import NumPyTimeBuilder >>> aniso8601.parse_time('11:31:14', builder=NumPyTimeBuilder) Traceback (most recent call last): File "", line 1, in File "/home/nielsenb/Jetfuse/numpytimebuilder/python2/lib/python2.7/site-packages/aniso8601/time.py", line 116, in parse_time return _RESOLUTION_MAP[get_time_resolution(timestr)](timestr, tz, builder) File "/home/nielsenb/Jetfuse/numpytimebuilder/python2/lib/python2.7/site-packages/aniso8601/time.py", line 165, in _parse_second_time return builder.build_time(hh=hourstr, mm=minutestr, ss=secondstr, tz=tz) File "numpytimebuilder/__init__.py", line 32, in build_time raise NotImplementedError('No compatible numpy time64 type.') NotImplementedError: No compatible numpy time64 type. Parsing durations ----------------- The NumPy :code:`timedelta64` type only supports a single component per delta, so durations are returned as a tuple of :code:`timedelta64` objects. To parse a duration formatted as an ISO 8601 string:: >>> import aniso8601 >>> from numpytimebuilder import NumPyTimeBuilder >>> aniso8601.parse_duration('P1Y2M3DT4H54M6S', builder=NumPyTimeBuilder) (numpy.timedelta64(428,'D'), numpy.timedelta64(4,'h'), numpy.timedelta64(54,'m'), numpy.timedelta64(6,'s'), numpy.timedelta64(0,'ms'), numpy.timedelta64(0,'us'), numpy.timedelta64(0,'ns'), numpy.timedelta64(0,'ps'), numpy.timedelta64(0,'fs'), numpy.timedelta64(0,'as')) Reduced accuracy is supported:: >>> aniso8601.parse_duration('P1Y', builder=NumPyTimeBuilder) (numpy.timedelta64(365,'D'), numpy.timedelta64(0,'h'), numpy.timedelta64(0,'m'), numpy.timedelta64(0,'s'), numpy.timedelta64(0,'ms'), numpy.timedelta64(0,'us'), numpy.timedelta64(0,'ns'), numpy.timedelta64(0,'ps'), numpy.timedelta64(0,'fs'), numpy.timedelta64(0,'as')) A decimal fraction is allowed on the lowest order element:: >>> aniso8601.parse_duration('P1YT3.5M', builder=NumPyTimeBuilder) (numpy.timedelta64(365,'D'), numpy.timedelta64(0,'h'), numpy.timedelta64(3,'m'), numpy.timedelta64(30,'s'), numpy.timedelta64(0,'ms'), numpy.timedelta64(0,'us'), numpy.timedelta64(0,'ns'), numpy.timedelta64(0,'ps'), numpy.timedelta64(0,'fs'), numpy.timedelta64(0,'as')) The decimal fraction can be specified with a comma instead of a full-stop:: >>> aniso8601.parse_duration('P1YT3,5M', builder=NumPyTimeBuilder) (numpy.timedelta64(365,'D'), numpy.timedelta64(0,'h'), numpy.timedelta64(3,'m'), numpy.timedelta64(30,'s'), numpy.timedelta64(0,'ms'), numpy.timedelta64(0,'us'), numpy.timedelta64(0,'ns'), numpy.timedelta64(0,'ps'), numpy.timedelta64(0,'fs'), numpy.timedelta64(0,'as')) Parsing a duration from a combined date and time is supported as well:: >>> aniso8601.parse_duration('P0001-01-02T01:30:5', builder=NumPyTimeBuilder) (numpy.timedelta64(397,'D'), numpy.timedelta64(1,'h'), numpy.timedelta64(30,'m'), numpy.timedelta64(5,'s'), numpy.timedelta64(0,'ms'), numpy.timedelta64(0,'us'), numpy.timedelta64(0,'ns'), numpy.timedelta64(0,'ps'), numpy.timedelta64(0,'fs'), numpy.timedelta64(0,'as')) The above treat years as 365 days and months as 30 days. Calendar level accuracy is not supported. Fractional years and months are supported accordingly:: >>> aniso8601.parse_duration('P2.1Y', builder=NumPyTimeBuilder) (numpy.timedelta64(766,'D'), numpy.timedelta64(12,'h'), numpy.timedelta64(0,'m'), numpy.timedelta64(0,'s'), numpy.timedelta64(0,'ms'), numpy.timedelta64(0,'us'), numpy.timedelta64(0,'ns'), numpy.timedelta64(0,'ps'), numpy.timedelta64(0,'fs'), numpy.timedelta64(0,'as')) >>> aniso8601.parse_duration('P1Y0.5M', builder=NumPyTimeBuilder) (numpy.timedelta64(380,'D'), numpy.timedelta64(0,'h'), numpy.timedelta64(0,'m'), numpy.timedelta64(0,'s'), numpy.timedelta64(0,'ms'), numpy.timedelta64(0,'us'), numpy.timedelta64(0,'ns'), numpy.timedelta64(0,'ps'), numpy.timedelta64(0,'fs'), numpy.timedelta64(0,'as')) Applying durations ^^^^^^^^^^^^^^^^^^ The :code:`apply_duration` helper function is provided for applying duration tuples to a :code:`datetime64` object. It takes a :code:`datetime64` (from :code:`parse_datetime`), a duration tuple (from :code:`parse_duration`), and a `Python operator `_ to be applied:: >>> import aniso8601 >>> import operator >>> from numpytimebuilder import NumPyTimeBuilder >>> from numpytimebuilder.util import apply_duration >>> datetime = aniso8601.parse_datetime('1977-06-10T12:00:00', builder=NumPyTimeBuilder) >>> duration = aniso8601.parse_duration('P3Y2M1DT1H2M3S', builder=NumPyTimeBuilder) >>> apply_duration(datetime, duration, operator.add) numpy.datetime64('1980-08-09T13:02:03') **Keep in mind the span of representable datetimes decreases as the resolution increases!** See the `NumPy Datetime Units `_ documentation for more information. Parsing intervals ----------------- To parse an interval specified by a start and end:: >>> import aniso8601 >>> from numpytimebuilder import NumPyTimeBuilder >>> aniso8601.parse_interval('2007-03-01T13:00:00/2008-05-11T15:30:00') (numpy.datetime64('2007-03-01T13:00:00'), numpy.datetime64('2008-05-11T15:30:00')) Intervals specified by a start time and a duration are supported:: >>> aniso8601.parse_interval('2007-03-01T13:00:00/P1Y2M10DT2H30M', builder=NumPyTimeBuilder) (numpy.datetime64('2007-03-01T13:00:00'), numpy.datetime64('2008-05-09T15:30:00')) A duration can also be specified by a duration and end time:: >>> aniso8601.parse_interval('P1M/1981-04-05', builder=NumPyTimeBuilder) (numpy.datetime64('1981-04-05'), numpy.datetime64('1981-03-06')) Notice that the result of the above parse is not in order from earliest to latest. If sorted intervals are required, simply use the :code:`sorted` keyword as shown below:: >>> sorted(aniso8601.parse_interval('P1M/1981-04-05', builder=NumPyTimeBuilder)) [numpy.datetime64('1981-03-06'), numpy.datetime64('1981-04-05')] The end of an interval is returned as a datetime when required to maintain the resolution specified by a duration, even if the duration start is given as a date:: >>> aniso8601.parse_interval('2014-11-12/PT4H54M6.5S', builder=NumPyTimeBuilder) (numpy.datetime64('2014-11-12'), numpy.datetime64('2014-11-12T04:54:06.500')) >>> aniso8601.parse_interval('2007-03-01/P1.5D', builder=NumPyTimeBuilder) (numpy.datetime64('2007-03-01'), numpy.datetime64('2007-03-02T12:00:00')) Repeating intervals are supported as well, and return a generator:: >>> aniso8601.parse_repeating_interval('R3/1981-04-05/P1D', builder=NumPyTimeBuilder) >>> list(aniso8601.parse_repeating_interval('R3/1981-04-05/P1D', builder=NumPyTimeBuilder)) [numpy.datetime64('1981-04-05'), numpy.datetime64('1981-04-06'), numpy.datetime64('1981-04-07')] Repeating intervals are allowed to go in the reverse direction:: >>> list(aniso8601.parse_repeating_interval('R2/PT1H2M/1980-03-05T01:01:00', builder=NumPyTimeBuilder)) [numpy.datetime64('1980-03-05T01:01:00'), numpy.datetime64('1980-03-04T23:59:00')] Unbounded intervals are also allowed (Python 2):: >>> result = aniso8601.parse_repeating_interval('R/PT1H2M/1980-03-05T01:01:00', builder=NumPyTimeBuilder) >>> result.next() numpy.datetime64('1980-03-05T01:01:00') >>> result.next() numpy.datetime64('1980-03-04T23:59:00') or for Python 3:: >>> result = aniso8601.parse_repeating_interval('R/PT1H2M/1980-03-05T01:01:00', builder=NumPyTimeBuilder) >>> next(result) numpy.datetime64('1980-03-05T01:01:00') >>> next(result) numpy.datetime64('1980-03-04T23:59:00') The above treat years as 365 days and months as 30 days. Calendar level accuracy is not supported. Fractional months and years are supported accordingly:: >>> aniso8601.parse_interval('P1.1Y/2001-02-28', builder=NumPyTimeBuilder) (numpy.datetime64('2001-02-28'), numpy.datetime64('2000-01-24')) >>> aniso8601.parse_interval('2001-02-28/P1Y2.5M', builder=NumPyTimeBuilder) (numpy.datetime64('2001-02-28'), numpy.datetime64('2002-05-14')) Development =========== Setup ----- It is recommended to develop using a `virtualenv `_. Inside a virtualenv, development dependencies can be installed automatically:: $ pip install -e .[dev] `pre-commit `_ is used for managing pre-commit hooks:: $ pre-commit install To run the pre-commit hooks manually:: $ pre-commit run --all-files Tests ----- Tests can be run using the `unittest testing framework `_:: $ python -m unittest discover numpytimebuilder Contributing ============ numpytimebuilder is an open source project hosted on `Codeberg `_. Any and all bugs are welcome on our `issue tracker `_. References ========== * `NumPy datetimes and timedeltas `_ * `aniso8601 and sub-microsecond precision `_