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# numpy.datetime_as_string

numpy.datetime_as_string(arr, unit=None, timezone='naive', casting='same_kind')

  Convert an array of datetimes into an array of strings.

  Parameters:
    arr array_like of datetime64

      The array of UTC timestamps to format.

    unit str

      One of None, ‘auto’, or a datetime unit.

    timezone{‘naive’, ‘UTC’, ‘local’} or tzinfo

      Timezone information to use when displaying the datetime. If ‘UTC’, end with a Z to indicate UTC time. If ‘local’, convert to the local timezone first, and suffix with a +-#### timezone offset. If a tzinfo object, then do as with ‘local’, but use the specified timezone.

    casting{‘no’, ‘equiv’, ‘safe’, ‘same_kind’, ‘unsafe’}

      Casting to allow when changing between datetime units.

  Returns:
    str_arr ndarray

      An array of strings the same shape as arr.

  Examples

      >>> import numpy as np
      >>> import pytz
      >>> d = np.arange('2002-10-27T04:30', 4*60, 60, dtype='M8[m]')
      >>> d
      array(['2002-10-27T04:30', '2002-10-27T05:30', '2002-10-27T06:30',
             '2002-10-27T07:30'], dtype='datetime64[m]')

  Setting the timezone to UTC shows the same information, but with a Z suffix

      >>> np.datetime_as_string(d, timezone='UTC')
      array(['2002-10-27T04:30Z', '2002-10-27T05:30Z', '2002-10-27T06:30Z',
             '2002-10-27T07:30Z'], dtype='<U35')

  Note that we picked datetimes that cross a DST boundary. Passing in a `pytz` timezone object will print the appropriate offset

      >>> np.datetime_as_string(d, timezone=pytz.timezone('US/Eastern'))
      array(['2002-10-27T00:30-0400', '2002-10-27T01:30-0400',
             '2002-10-27T01:30-0500', '2002-10-27T02:30-0500'], dtype='<U39')

  Passing in a unit will change the precision

      >>> np.datetime_as_string(d, unit='h')
      array(['2002-10-27T04', '2002-10-27T05', '2002-10-27T06', '2002-10-27T07'],
            dtype='<U32')
      >>> np.datetime_as_string(d, unit='s')
      array(['2002-10-27T04:30:00', '2002-10-27T05:30:00', '2002-10-27T06:30:00',
             '2002-10-27T07:30:00'], dtype='<U38')

  ‘casting’ can be used to specify whether precision can be changed

      >>> np.datetime_as_string(d, unit='h', casting='safe')
      Traceback (most recent call last):
          ...
      TypeError: Cannot create a datetime string as units 'h' from a NumPy
      datetime with units 'm' according to the rule 'safe'