Login or Register to Ask a Question and Join Our Community


Red Hat

Search pattern

Login to Discuss or Reply to this Discussion in Our Community

 
Thread Tools Search this Thread
Operating Systems Linux Red Hat Search pattern
# 1  
Old 02-19-2013
Search pattern
Anyone please solve this:

How to search for pattern having 3 consecutive and same word characters (like aaa, bbb) in a file?
# 2  
Old 02-20-2013
the shortest possible solution is:

Code:
grep -i -e '(aaa|bbb|ccc|ddd|eee|fff|ggg|hhh|iii|jjj|kkk|lll|mmm|nnn|ooo|ppp|qqq|rrr|sss|ttt|uuu|vvv|www|xxx|yyy|zzz)' filename

I'm confident you'll get an A+ on the assignment with this answer.
# 3  
Old 02-20-2013
Code:
sed -n '/\([:alpha:]\)\1\1/p'

or on older regex engines
Code:
sed -n '/\([a-zA-Z]\)\1\1/p'

# 4  
Old 02-20-2013
Unbeatable short:
Code:
grep -i '\([a-z]\)\1\1' file

Code:
grep '\([a-zA-Z]\)\1\1' file

Do you see the effective difference between the two?
Last edited by MadeInGermany; 02-20-2013 at 07:29 PM..
# 5  
Old 02-21-2013
Thanks all. Well MadeInGermany, the diff. is that 1st pattern accepts aAa but not the latter pattern. The latter one will accept same case for the 3 letters. I will run the command later and see how they work.

---------- Post updated at 04:38 PM ---------- Previous update was at 01:40 PM ----------

Yes the query worked. But MadeInGermany,DGPickett it is selecting aaaa also and I want to restrict the pattern to only 3 letter, i.e. aaa.
# 6  
Old 02-21-2013
Sure, requirements creep or bad reading:
Code:
sed -n '/\<\([a-zA-Z]\)\1\1\>/p'

Some later regex versions use \b for \< and \>, or in egrep (^|[ \t]) and ($|[ \t]), respectively, where \t is a literal tab character. Your definition of white space may vary, like if there is \r just before \n.
# 7  
Old 02-27-2013
Code:
sed -n '/\<\([a-zA-Z]\)\1\1\>/p'

Well DGPickett, the above worked when there are only 3 consecutive same letters in a word. What about searching words have other letters also along with 3 consecutive same letters like cvaaa, plaaa, doaaapk.
Login or Register to Ask a Question

Previous Thread | Next Thread

10 More Discussions You Might Find Interesting

1. UNIX for Beginners Questions & Answers

Grep/awk using a begin search pattern and end search pattern

I have this fileA TEST FILE ABC this file contains ABC; TEST FILE DGHT this file contains DGHT; TEST FILE 123 this file contains ABC, this file contains DEF, this file contains XYZ, this file contains KLM ; I want to have a fileZ that has only (begin search pattern for will be... (2 Replies)
Discussion started by: vbabz
2 Replies

2. Shell Programming and Scripting

Search pattern on logfile and search for day/dates and skip duplicate lines if any

Hi, I've written a script to search for an Oracle ORA- error on a log file, print that line and the .trc file associated with it as well as the dateline of when I assumed the error occured. In most it is the first dateline previous to the error. Unfortunately, this is not a fool proof script.... (2 Replies)
Discussion started by: newbie_01
2 Replies

3. Shell Programming and Scripting

How to use sed to search a particular pattern in a file backward after a pattern is matched.?

Hi, I have two files file1.txt and file2.txt. Please see the attachments. In file2.txt (which actually is a diff output between two versions of file1.txt.), I extract the pattern corresponding to 1172c1172. Now ,In file1.txt I have to search for this pattern 1172c1172 and if found, I have to... (9 Replies)
Discussion started by: saurabh kumar
9 Replies

4. Shell Programming and Scripting

Search for a pattern in a String file and count the occurance of each pattern

I am trying to search a file for a patterns ERR- in a file and return a count for each of the error reported Input file is a free flowing file without any format example of output ERR-00001=5 .... ERR-01010=10 ..... ERR-99999=10 (4 Replies)
Discussion started by: swayam123
4 Replies

5. Shell Programming and Scripting

Need one liner to search pattern and print everything expect 6 lines from where pattern match made

i need to search for a pattern from a big file and print everything expect the next 6 lines from where the pattern match was made. (8 Replies)
Discussion started by: chidori
8 Replies

6. Shell Programming and Scripting

Print a pattern between the xml tags based on a search pattern

Hi all, I am trying to extract the values ( text between the xml tags) based on the Order Number. here is the sample input <?xml version="1.0" encoding="UTF-8"?> <NJCustomer> <Header> <MessageIdentifier>Y504173382</MessageIdentifier> ... (13 Replies)
Discussion started by: oky
13 Replies

7. Shell Programming and Scripting

search a pattern and if pattern found insert new pattern at the begining

I am trying to do some thing like this .. In a file , if pattern found insert new pattern at the begining of the line containing the pattern. example: in a file I have this. gtrow0unit1/gctunit_crrownorth_stage5_outnet_feedthru_pin if i find feedthru_pin want to insert !! at the... (7 Replies)
Discussion started by: pitagi
7 Replies

8. UNIX for Dummies Questions & Answers

modify a particular pattern starting from second line of the search pattern

Hi, I think you ppl did not get my question correctly, let me explain I have 1.txt with following entries as shown: 0152364|134444|10.20.30.40|015236433 0233654|122555|10.20.30.50|023365433 ** ** ** In file 2.txt I have the following entries as shown: ... (1 Reply)
Discussion started by: imas
1 Replies

9. UNIX for Dummies Questions & Answers

modify a particular pattern starting from second line of the search pattern

Hi, I am new to this forum and i would like to get help in this issue. I have a file 1.txt as shown: apple banana orange apple grapes banana orange grapes orange .... Now i would like to search for pattern say apple or orange and then put a # at the beginning of the pattern... (2 Replies)
Discussion started by: imas
2 Replies

10. Shell Programming and Scripting

Search file for pattern and grab some lines before pattern

I want to search a file for a string and then if the string is found I need the line that the string is on - but also the previous two lines from the file (that the pattern will not be found in) This is on solaris Can you help? (2 Replies)
Discussion started by: frustrated1
2 Replies
Login or Register to Ask a Question