Some special postcodes are used in addresses, such as codes for post office boxes. This helper converts those to the postcode for the closest normal suburb if there is a reasonable clear match. If there is no good match, the postcodes are left unchanged.
normalise_postcodes(codes)
Arguments
codes: Character vector of postcodes (or coercible to one).
Returns
Character vector of the same size as the input, but with the normalised postcodes.
Details
Note that this goes a little further than the aliases that are registered with cartographer (which only account for postcodes with no geospatial data in the ABS dataset).