# If you'd like to omit non-matching lines from the result; add ';d' to the end of the expression.
sed -E 's/(?i).*?\bfloor area:?\s*(\d+).*/\1/g;t' <<< "A beautiful flat on the 3rd floor with floor area: 50 sqm and a lift
Newbuild flat. Floor Area: 30 sq.m\",\"6 bed house with floor area 50 sqm, lot area 25 sqm
6 bed house with floor area 50 sqm, lot area 25 sqm"
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for SED, please visit: https://www.gnu.org/software/sed/manual/html_node/The-_0022s_0022-Command.html