Identifying Custom Australian Licence Plates
In case this saves anyone some time, here’s a quick bit of regex and Python code for identifying if a given licence plate is standard or custom (personalised) in a given state.
I can’t promise that this logic is correct or up to date. Some of the rules used are a bit more general than they need to be. I also tended to ignore rules before 1970. The rules come from:
- https://en.wikipedia.org/wiki/Vehicle_registration_plates_of_Australia
- https://www.vicroads.vic.gov.au/registration/number-plates/general-issue-number-plates
import re
# Takes a pattern like xxxddd (for three letters followed by three numbers)
# and converts it to regex. Other characters are left as is in the regex
# pattern string. This is helpful for states like SA in which every modern
# licence plate begins with an "S".
def match_plate_pattern(plate, pattern):
pattern = pattern.replace('x','[A-Za-z]').replace('d','[0-9]')
return(re.fullmatch(pattern, plate))
licence_plate_patterns = {
"VIC": ["dxxdxx", # current car
"xxxddd", # old car
"dxdxx", # current motorcycle
"xxddd"], # old motorcycle
"NSW": ["xxddxx", # current car
"xxxddx", # old car
"xxxdd"], # motorcycles
"QLD": ["dddxxx", # current car
"dddxxd", # future car
"dddxx"], # motorcycles
"SA": ["Sdddxxx", # current car
"dddxxx", # old car
"Sddxxx", # current motorcycles
"ddxxx"], # old motorcycles
"WA": ["1xxxddd", # current style plates
"xxxddd", # old style plates before 1978
"dxxddd", # old style plates 1978--1997
"1ddxxx"], # current motorcycles (1997 onwards)]
"TAS": ["xddxx", # current style plates
"xxdddd", # old style plates 1970--2008
"xxxddd", # old style plates 1954--1970
"xxddd", # motorcycles
"xdddx"], # motorcycles
"ACT": ["xxxddx", # current style plates
"xxxddd", # future style plates
"xdddd"], # motorcycles
"NT": ["xxddxx", # current style plates
"dddddd", # future style plates
"xdddd", # current motorcycles
"ddddd"] # old motorcycles 1979--2011
}
def plate_type(plate, state):
# remove anything that isn't a letter or number
plate = re.sub(r'[\W_]+', '', str(plate))
plate_matches = [match_plate_pattern(plate, pattern) for pattern
in licence_plate_patterns[state]]
if plate == "":
return("no_plate")
elif any(plate_matches):
return("standard_plate")
else:
return("custom_plate")And some Victorian examples:
plate_type("ABC-123", "VIC")
#> 'standard_plate'
plate_type("XY123", "VIC")
#> 'standard_plate'
plate_type("1AB-2CD", "VIC")
#> 'standard_plate'
plate_type("HOTROD", "VIC")
#> 'custom_plate'The image at the top of this page is in the public domain.
devtools::session_info()
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