original_docstring: Open or download three time scale files, returning a `Timescale`.
  
          This method is how most Skyfield users build a `Timescale`
          object, which is necessary for building specific `Time` objects
          that name specific moments.
  
          This will open or download the three files that Skyfield needs
          to measure time.  UT1 is tabulated by the United States Naval
          Observatory files ``deltat.data`` and ``deltat.preds``, while
          UTC is defined by ``Leap_Second.dat`` from the International
          Earth Rotation Service.
  
          If ``builtin`` is ``True`` then instead of downloading the
          files, Skyfield will load a version of each file that it ships
          internally.  Beware that these files will gradually fall out of
          date as you use one particular version of Skyfield.
  
          
docstring: Open or download three time scale files, returning a `Timescale`.
  This method is how most Skyfield users build a `Timescale`
  object, which is necessary for building specific `Time` objects
  that name specific moments.
  
  This will open or download the three files that Skyfield needs
  to measure time.
  
  
docstring_tokens: Open or download three time scale files returning a ` Timescale ` . This method is how most Skyfield users build a ` Timescale ` object which is necessary for building specific ` Time ` objects that name specific moments . This will open or download the three files that Skyfield needs to measure time .
code: def timescale(self, delta_t=None, builtin=False):
          """Open or download three time scale files, returning a `Timescale`.
  
          This method is how most Skyfield users build a `Timescale`
          object, which is necessary for building specific `Time` objects
          that name specific moments.
  
          This will open or download the three files that Skyfield needs
          to measure time.  UT1 is tabulated by the United States Naval
          Observatory files ``deltat.data`` and ``deltat.preds``, while
          UTC is defined by ``Leap_Second.dat`` from the International
          Earth Rotation Service.
  
          If ``builtin`` is ``True`` then instead of downloading the
          files, Skyfield will load a version of each file that it ships
          internally.  Beware that these files will gradually fall out of
          date as you use one particular version of Skyfield.
  
          """
          if builtin:
              b = get_data('skyfield', 'data/deltat.data')
              expiration_date, data = parse_deltat_data(BytesIO(b))
              b = get_data('skyfield', 'data/deltat.preds')
              expiration_date, preds = parse_deltat_preds(BytesIO(b))
              data_end_time = data[0, -1]
              i = np.searchsorted(preds[0], data_end_time, side='right')
              delta_t_recent = np.concatenate([data, preds[:,i:]], axis=1)
  
              b = get_data('skyfield', 'data/Leap_Second.dat')
              expiration_date, arrays = parse_leap_seconds(BytesIO(b))
              leap_dates, leap_offsets = arrays
  
              return Timescale(delta_t_recent, leap_dates, leap_offsets)
  
          if delta_t is not None:
              delta_t_recent = np.array(((-1e99, 1e99), (delta_t, delta_t)))
          else:
              try:
                  data = self('deltat.data')
                  preds = self('deltat.preds')
              except IOError as e:
                  e.args = (e.args[0] + _TIMESCALE_IO_ADVICE,) + e.args[1:]
                  raise
              data_end_time = data[0, -1]
              i = np.searchsorted(preds[0], data_end_time, side='right')
              delta_t_recent = np.concatenate([data, preds[:,i:]], axis=1)
          leap_dates, leap_offsets = self('Leap_Second.dat')
          return Timescale(delta_t_recent, leap_dates, leap_offsets)
code_tokens: def timescale ( self , delta_t = None , builtin = False ) : if builtin : b = get_data ( 'skyfield' , 'data/deltat.data' ) expiration_date , data = parse_deltat_data ( BytesIO ( b ) ) b = get_data ( 'skyfield' , 'data/deltat.preds' ) expiration_date , preds = parse_deltat_preds ( BytesIO ( b ) ) data_end_time = data [ 0 , - 1 ] i = np . searchsorted ( preds [ 0 ] , data_end_time , side = 'right' ) delta_t_recent = np . concatenate ( [ data , preds [ : , i : ] ] , axis = 1 ) b = get_data ( 'skyfield' , 'data/Leap_Second.dat' ) expiration_date , arrays = parse_leap_seconds ( BytesIO ( b ) ) leap_dates , leap_offsets = arrays return Timescale ( delta_t_recent , leap_dates , leap_offsets ) if delta_t is not None : delta_t_recent = np . array ( ( ( - 1e99 , 1e99 ) , ( delta_t , delta_t ) ) ) else : try : data = self ( 'deltat.data' ) preds = self ( 'deltat.preds' ) except IOError as e : e . args = ( e . args [ 0 ] + _TIMESCALE_IO_ADVICE , ) + e . args [ 1 : ] raise data_end_time = data [ 0 , - 1 ] i = np . searchsorted ( preds [ 0 ] , data_end_time , side = 'right' ) delta_t_recent = np . concatenate ( [ data , preds [ : , i : ] ] , axis = 1 ) leap_dates , leap_offsets = self ( 'Leap_Second.dat' ) return Timescale ( delta_t_recent , leap_dates , leap_offsets )
short_docstring: Open or download three time scale files, returning a `Timescale`.
short_docstring_tokens: Open or download three time scale files returning a ` Timescale ` .
comment: """Open or download three time scale files, returning a `Timescale`.
  
          This method is how most Skyfield users build a `Timescale`
          object, which is necessary for building specific `Time` objects
          that name specific moments.
  
          This will open or download the three files that Skyfield needs
          to measure time.  UT1 is tabulated by the United States Naval
          Observatory files ``deltat.data`` and ``deltat.preds``, while
          UTC is defined by ``Leap_Second.dat`` from the International
          Earth Rotation Service.
  
          If ``builtin`` is ``True`` then instead of downloading the
          files, Skyfield will load a version of each file that it ships
          internally.  Beware that these files will gradually fall out of
          date as you use one particular version of Skyfield.
  
          """