Consider the following input string.
PLOG_NFET_SLVT nf=3 ng=1 nl=20n
PLOG_NFET_LVT nf=3 ng=1 nl=14n
Note: 1st and last word are replaced. Also in between data varies. So I can not have a constant pattern. I tried using below command.
sed -i 's/PLOG.*FET_SLVT.*nl=20n/PLOG.*FET_LVT.*nl=14n/g' file
and output is :