[linux] awk

How to use "awk" (it is really cool!)

1. When you want to make a new file from data file with several fields:

awk '{print $1, $3}' simulation.d > total.d

2. If you want to extract certain conditioned field:

awk '$1>100 && $1<1 {print $0}' total.d > data.d

3. When you want to sum up the elements in the column:

awk 'x+=$2 {print x}' data.d

4. line number: you can print line number "NR"

awk '{print NR $2}' data.d