Login or Register to Ask a Question and Join Our Community


Shell Programming and Scripting

sed question

Login to Discuss or Reply to this Discussion in Our Community

 
Thread Tools Search this Thread
Top Forums Shell Programming and Scripting sed question
# 1  
Old 02-19-2010
sed question
lets say i have a file with any number of records i want to read each record n extract the characters from col 4 through 8 , how can i do that ?

Code:
2131231313123121121
1312131321231212121
2131213121231212121

Last edited by zxmaus; 02-19-2010 at 07:46 PM..
# 2  
Old 02-19-2010
Code:
sed "s/...\(.....\).*/\1/" file1

It's easier with cut...
Code:
cut -c4-8 file1

# 3  
Old 02-19-2010
i was doing this but i had to do echo $line | cut -c 4-8
but it is very slow
will sed speed it up ?
# 4  
Old 02-19-2010
You were doing this in a loop?

i.e. something like:
Code:
while read line; do
  echo $line | cut -c 4-8
done < file

Code:
cut -c4-8 file

will be a magnitude quicker.

I don't think sed will be quicker than cut, when used on its own like this.
# 5  
Old 02-22-2010
yes i was doing it in a loop
cause i have to add the values in these column positions as i read them , can i do it in sed also without looping through the files ?
# 6  
Old 02-22-2010
Try:

Code:
sed -e 's/\(.\{3\}\)\(.\{5\}\).*/\2/' -e 's/./&+/g' -e 's/.*/(( v =&0 )); echo $v;/g' file | sh

input:
Code:
2131231313123121121
1312131321231212121
2131213121231212121

output:
Code:
10
10
8

# 7  
Old 02-22-2010
Code:
$ cat data
2131231313123121121
1312131321231212121
2131213121231212121

$ awk -v FS="" '{x=0; for (i=4;i<9;i++) x+=$i; print x}' data
10
10
8

Although the behavior of splitting each character into a field when FS is a null string is not standardized by POSIX, it seems to be fairly well supported by different AWK implementations.

Cheers,
Alister
Login or Register to Ask a Question

Previous Thread | Next Thread

10 More Discussions You Might Find Interesting

1. UNIX for Dummies Questions & Answers

SED question

I am trying to write a script that will take an input text file in the format person: place: phonenumber; person: place: phonenumber; person: place: phonenumber; ... and output it using sed too: Name ######## Location ######### Phone Number... (1 Reply)
Discussion started by: jmack56
1 Replies

2. Shell Programming and Scripting

Sed question

I need to replace the numbers with a new string. How can I give a wildcard for the different # of numbers sed '/abcdef/s/abcdef=*/abcdef=999999/'<foo>foo1 From: To: abcdef=1234 abcdef=999999 abcdef=12345 abcdef=999999 abcdef=123456... (10 Replies)
Discussion started by: beppler
10 Replies

3. Shell Programming and Scripting

sed question

hi i have a file with this line: variable=/export/home/oracle I want to change the file so that the path is replaced with the value of another variable var2=/tmp/anything. how to do this in sed? thx (4 Replies)
Discussion started by: melanie_pfefer
4 Replies

4. Shell Programming and Scripting

Sed Question 1. (Don't quite know how to use sed! Thanks)

Write a sed script to extract the year, rank, and stock for the most recent 10 years available in the file top10_mktval.csv, and output in the following format: ------------------------------ YEAR |RANK| STOCK ------------------------------ 2007 | 1 | Exxon... (1 Reply)
Discussion started by: beibeiatNY
1 Replies

5. UNIX for Dummies Questions & Answers

sed question

How would I use sed to print everything on the line after the regular expresion? I have a configuration file setting several variables. cfg.dat DDB = cpptest SUDBNAME = sucpptestdb host = cpptest Example I want to search for the regular expresion 'SUDBNAME =' and print everything on... (3 Replies)
Discussion started by: orahi001
3 Replies

6. Shell Programming and Scripting

sed question

I have a file that conatins following info Policy1=U|guestRoom=test1idCode=5(1):!:Amenity2=U|RoomId=testrma=4(1):!:| GuestRoomAmenity1=U|guestRoomId=testguest1id^rmaCode=5(1):!:| I need it to look like this Policy1=U|guestRoom=test1idCode Amenity2=U|RoomId=testrmaCode... (2 Replies)
Discussion started by: arushunter
2 Replies

7. Shell Programming and Scripting

sed question

Hi, :) can any body explain the following statement sed 's/\(\)- ]//g' cheers RRK (3 Replies)
Discussion started by: ravi raj kumar
3 Replies

8. Shell Programming and Scripting

sed question

Hi, When deleting lines using sed, as i understand the lines are redirected to the standard output. What i'm unclear about is how to actually modify the file? If I write the command sed '1,2d' test it will display lines one and 2 onto the screen however the file is not modified? I think my... (5 Replies)
Discussion started by: c19h28O2
5 Replies

9. Shell Programming and Scripting

sed question (again)

hello there, I have a sed question. I have a file (temp.srv), in it it has v1_host1 v2_host2 And I have another file (temp2.srv), in it is has v1_host3_date v1_host1 v2_host2 v2_host4_date v3_host5_date I had used a script to remove the name from temp2.srv base on the name inside... (3 Replies)
Discussion started by: ahtat99
3 Replies

10. Shell Programming and Scripting

Sed Question

Hi, Is there any way to traverse the file once and look for the following conditions in one sweep instead of going over the file 3 times with different search criteria...... sed -n '/^ORA-07445/ p' /tmp/t$$ > ${OERRFILE} sed -n '/^ORA-00600/ p' /tmp/t$$ >> ${OERRFILE} ... (1 Reply)
Discussion started by: YS2002
1 Replies
Login or Register to Ask a Question