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Example of the regular expression feature for querying (6), constraining (7) and extracting (8) a numeric concept (Puls = pulse, ZAHL = NUMBER). “$1” is a reference to the extracted concept (the first expression in round parentheses or its equivalent predefined class, i.e. “ZAHL”).
| Syntax | Alternative Syntax | |
|---|---|---|
| /Puls ZAHL/ | /Puls [0–9]+/ | (6) |
| /Puls ZAHL/[ZAHL > 150] | /Puls ([0–9]+)/[$1 > 150] | (7) |
| /Puls ZAHL/[ZAHL > 150] ZAHL | /Puls ([0–9]+)/[$1 > 150] $1 | (8) |
