Question

I would like to replace a handful of strings with others (e.g. “GG” with “GGX”, “GG ” with “GGX”, “FG” with “FGX”, etc) in the first column of a big csv file using a shell command.

I know I need something like

big.csv shell_commands big.csv

but I don’t know awk or sed

Answer 1

Using sed, replacing all instances of “GG” with “GGX” in big.csv would look like:

sed 's/^GG/GGX/g' big.csv >big_translated.csv

If you need to replace multiple patterns, you can use multiple replace commands in sed separated by semicolons.

sed 's/^GG/GGX/g; s/^FG/FGX/g' big.csv >big_translated.csv

The ^ character means beginning of line and ensures that we only edit the first field of the csv.