This regex patterns allows to parse rinex 2 filesnames/filepath it follows the directory structure usually found on FTP servers from main GNSS CORS stations networks / monitoring organizations (e.g. ftp://rgpdata.ign.fr/pub/data)

^(?:20-4|25[0-5]|1?[0-9]?[0-9]).[0-9]|25[0-5]|1?[0-9]?[0-9]).[0-9]|25[0-5]|1?[0-9]?[0-9]).[0-9]|25[0-5]|1?[0-9]?[0-9])$mgs

YYYYMMDD YYYY-MM-DD YYYY.MM.DD YYYY/MM/DD YYYY-M-D YYYY.M.D...

Ensure the ip address format is correct

for quadratic equations ||ax^2+bx+c=d||

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