Encode text phonetically with the Cologne procedure

The Cologne phonetic procedure (Koelner Phonetik) is the German-language counterpart to Soundex. It maps text to a digit string by German pronunciation rules, so variants like "Meier", "Maier", and "Mayer" share one key. Reach for this over as_soundex() or as_metaphone() when the data is German.

Usage

as_cologne(text)

Arguments

text

A character string or vector to encode, or a token list-column (one character vector of tokens per row) when the encoder is placed after a token generator – each token is then encoded in place.

Value

A character vector of Cologne phonetic keys (digit strings), one per input element.

Details

Returns text, so it slots ahead of a token generator, or use it directly on a one-word column. Like any phonetic key it favours recall over precision; pair it with a sharper field rather than matching on the key alone.

See also

Other phonetic encoders: as_metaphone(), as_soundex()

Examples

as_cologne(c("Meier", "Maier", "Mayer"))  # same key
#> [1] "67" "67" "67"