Code to only keep words that are 7 characters or less and delete all others?

[Rytron]

Hi.

Can someone give me code that will take a text file with many words and only keep those that are 7 characters or less and delete all others?

Thanks.

[erind]

Try this perl code:

perl -pe 's/\b\w{8,}\b//g'  filename

[Rytron]

Try this perl code:

perl -pe 's/\b\w{8,}\b//g'  filename

Cool, nice one erind.
I added "> file2.txt" to copy the selected text to a new file.

perl -pe 's/\b\w{9,}\b//g' file1.txt > file2.txt

Would it be possible to leave all words of 7 chars or less in the original file and delete all other words? No problem if not as the initial code is great.

[erind]

[...]

Would it be possible to leave all words of 7 chars or less in the original file and delete all other words? No problem if not as the initial code is great.

Yes, use the -i (inplace) option, but take extra care when using it - it overwrites the original file:

perl -i -pe 's/\b\w{8,}\b//g'  file1.txt

Another option is keeping a backup of the original file (file1.txt.bak), while modifying the original (file1.txt):

perl -i.bak -pe 's/\b\w{8,}\b//g'  file1.txt

Yet another common (shell) way is using a temporary file:

perl -pe '...'  file1.txt > temp && mv temp file1.txt

[Rytron]

Cheers erind. You are a code wizard.