Comments on: Homework 2 – More UNIX basics and regular expressions

By: robfelty

robfelty — Fri, 11 Sep 2009 19:47:27 +0000

You should limit your search to only the orthography of the words.

By: kelleya

kelleya — Fri, 11 Sep 2009 19:03:39 +0000

Hi Rob,

For question 7 I’m able to limit my search to words that contain ‘q’ not followed by ‘u’ but when printing just the orthography I’m getting all words that have a string of q not followed by u somewhere in the definition or description.
i.e. “gendarme” is one of the words in the printed list, for which in its full entry is:
36631\gendarme\13\18700\6\’Zqn-d#m\[CVVC][CVVC]\[ZA~:n][dA:m]\Zandarm\3.6667.0000\HML\Z’an

since "Zqn" fits the criteria of my search. Is this ok or do I need to get my pipeline to only print words from the entries?

Thanks,
Arrick

By: robfelty

robfelty — Fri, 11 Sep 2009 16:07:16 +0000

Backslash will not escape single or double quotes. You have two options,
1. use double quotes, e.g.
grep “don’t” file
2. Don’t use any quotes, but then you have to escape every special character
grep d\[ao\]n\’t celex.txt
Then to actually match special characters, you have to double escape them. e.g.
grep CVVCC\\]\\[CVVC celex.txt

All that having been said, it might be easier to use a negative character class.

By: keith.mertz

keith.mertz — Fri, 11 Sep 2009 15:29:31 +0000

Does the backslash properly function as an escape character for the single quote mark, or must I (if even possible) use some other sorcery to grep for, say, a possessive? When I use a regular expression such as ‘^[A-Z\']*’ in the hopes of capturing something like “HUGH’S”, the terminal just stares back at me with eyes glazed and spittle dribbling down its chin.

I feel like this had to have been mentioned, so I apologize (if so) for asking again. Thanks in advance for enlightenment!

By: robfelty

robfelty — Wed, 09 Sep 2009 19:15:57 +0000

Les,

Here is an example.
cat n., a furry domesticated animal of the feline family

“cat” is the entry. Everything after the comma is the definition

Look at the last example in the GREP chapter of the notes for an example. I will also go over this in class tomorrow.

By: sikos

sikos — Wed, 09 Sep 2009 16:38:05 +0000

Hi Rob,
Not sure what you mean by “entries (not definitions”. Is there a readme that goes along with this file?
Les