Examples

Examples:

    fixplanets('uid___A002_X1c6e54_X223.ms', 'Titan', True)
          will look up the pointing direction from antenna 0 for field 'Titan' in
          the POINTING table based on the first timestamp in the main table rows for
          this field, enter this direction in the FIELD and SOURCE tables, and then
          recalculate the UVW coordinates for this field.

    fixplanets('uid___A002_X1c6e54_X223.ms', 'Titan', True, 'Titan_55438-56292dUTC.tab')
          will attach the ephemeris table 'Titan_55438-56292dUTC.tab' to field 'Titan'
          and then recalculate the UVW coordinates for this field.

    fixplanets('uid___A002_X1c6e54_X223.ms', 'Titan', False, 'J2000 12h30m15 -02d12m00')
          will set the directions for field 'Titan' in the FIELD and SOURCE table to the
          given direction and not recalculate the UVW coordinates.
          (This can be useful for several purposes, among them preparing a concatenation
          of datasets. Only fields with the same direction will be recognised as identical.
          fixplanets can then be run again after the concatenation using parameters as in
          the first example above.)