checkdigit.verhoeff.missing¶

checkdigit.verhoeff.missing(data: str) → str[source]¶

Calculates a missing digit in a Verhoeff code.

Parameters:: data – A string of characters representing a full Verhoeff code with a question mark for a missing character
Returns:: The missing value that should’ve been where the question mark was
Return type:: str

Examples

>>> from checkdigit import verhoeff
>>> verhoeff.missing("23?3")
'6'
>>> verhoeff.missing("999?")
'8'
>>> verhoeff.missing("123")
'Invalid'