Login or Register to Ask a Question and Join Our Community

Sponsored Content
Full Discussion: Extracting fixed length number from a text file
Top Forums Shell Programming and Scripting Extracting fixed length number from a text file Post 302994218 by Scrutinizer on Monday 20th of March 2017 01:01:26 PM
Old 03-20-2017
Quote:
Originally Posted by dsid
[..]

@Scrutinizer: true my command did print out numbers more than 23 in length.


Code:
grep  -Eo '\<[0-9]{23}\>' file

the above command should work perfect as square brackets wont be in delimiters always so the awk command wont work in all occasions.

I am kinda confused as to why we are using single quotes in a grep expression. Cos I was reading the other day that single quotes remove any meaning from the special characters. Shouldn't we use double quotes?

Also the fact the you have used <,>. Are they working as a block to extract only 23 digits numbers/characters?
[..]
Hi dsid

The single quotes are better at protecting the regular expression from the shell, than double quotes, so that is why I prefer to use them. When you read that they remove any meaning from the special characters, they meant shell special characters, not regex special characters ...

\< and \> are word boundary operators and match the empty string at the beginning/end of a word respectively..

So if the 23 digits are enclosed by anything other than word characters ( [0-9A-Za-z_], or more precisely: [[:alnum:]_] , including the start or end of a line) then it will match the 23 digits.
Last edited by Scrutinizer; 03-20-2017 at 02:08 PM..
This User Gave Thanks to Scrutinizer For This Post:
dsid
 

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

creating a fixed length output from a variable length input

Is there a command that sets a variable length? I have a input of a variable length field but my output for that field needs to be set to 32 char. Is there such a command? I am on a sun box running ksh Thanks (2 Replies)
Discussion started by: r1500
2 Replies

2. Shell Programming and Scripting

convert XML file into Text file(fixed length)

If someone out there could help me out with this problem. I would really appreciate it. I am trying to convert xml into text file(fixed length) using Unix Borne shell scripts. My xml file: <root> <header_rec recordtype="00"> <record_id>00</record_id> ... (0 Replies)
Discussion started by: ram2s2001
0 Replies

3. UNIX for Dummies Questions & Answers

What the command to find out the record length of a fixed length file?

I want to find out the record length of a fixed length file? I forgot the command. Any body know? (9 Replies)
Discussion started by: tranq01
9 Replies

4. UNIX for Dummies Questions & Answers

Convert a tab delimited/variable length file to fixed length file

Hi, all. I need to convert a file tab delimited/variable length file in AIX to a fixed lenght file delimited by spaces. This is the input file: 10200002<tab>US$ COM<tab>16/12/2008<tab>2,3775<tab>2,3783 19300978<tab>EURO<tab>16/12/2008<tab>3,28523<tab>3,28657 And this is the expected... (2 Replies)
Discussion started by: Everton_Silveir
2 Replies

5. Shell Programming and Scripting

fixed length text file padding issues in AIX

Hi, I have a fixed length text file that needs to be cut into individual files in aix and facing padding issues. If I have multiple blank spaces in the file it is just making it one while cutting the files.. Eg:- $ - blank space filename:file.txt ... (2 Replies)
Discussion started by: techmoris
2 Replies

6. Shell Programming and Scripting

changing a variable length text to a fixed length

Hi, Can anyone help with a effective solution ? I need to change a variable length text field (between 1 - 18 characters) to a fixed length text of 18 characters with the unused portion, at the end, filled with spaces. The text field is actually field 10 of a .csv file however I could cut... (7 Replies)
Discussion started by: dc18
7 Replies

7. Shell Programming and Scripting

Help with extracting words from fixed length files

I am very new to scripting and need to write a script that will extract the account number from a line that begins with HDR. For example, the file is as follows HDR2010072600300405505100726 00300405505 LBJ FREEWAY DALLAS TELEGRAPH ... (9 Replies)
Discussion started by: bds052189
9 Replies

8. Shell Programming and Scripting

Insert a variable to a text file after fixed number of lines

Hi, I am new to unix. I need to insert a variable which contains some lines of text into a text file after fixed number of lines.. Please help me on this.. Thanks in Advance, Amrutha (3 Replies)
Discussion started by: amr89
3 Replies

9. UNIX for Dummies Questions & Answers

Fixed length file extracting values in columns

How do I extract values in a few columns in a row of a fixed length file? If there are 8 columns and I need to extract values of 2nd,4th and 6 th columns, how do i do that? I used cut command, this I used only for one column. How do I do it more than one column? The below command will give... (1 Reply)
Discussion started by: princetd001
1 Replies

10. UNIX for Dummies Questions & Answers

Length of a fixed width file

I have a fixed width file of length 53. when is try to get the lengh of the record of that file i get 2 different answers. awk '{print length;exit}' <File_name> The above code gives me length 50. wc -L <File_name> The above code gives me length 53. Please clarify on... (2 Replies)
Discussion started by: Amrutha24
2 Replies

LEARN ABOUT DEBIAN

empty-page

EMPTY-PAGE(1)							 ExactImage Manual						     EMPTY-PAGE(1)

NAME

       empty-page - empty page detector of the ExactImage toolkit

SYNOPSIS

       empty-page [option...] {-i | --input} input-file

       empty-page {-h | --help}

DESCRIPTION

       ExactImage is a fast C++ image processing library. Unlike many other library frameworks it allows operation in several color spaces and bit
       depths natively, resulting in low memory and computational requirements.

       empty-page counts dark pixels of a black and white image and decides with a threshold whether the page is most probably empty, and thus can
       be removed from the image processing stream.

OPTIONS

       -i file, --input file
	   Read image from the specified file.

       -m n, --margin n
	   Set width of border margin to skip. For speed reasons, the margin has to be a multiple of 8. The default is 16.

       -p x, --percentage x
	   Set fraction of permissible dark pixels. The default is 0.05 (5%).

       -h, --help
	   Display help text and exit.

EXAMPLES

	   $ empty-page -i test.tif
	   The image has 75461 dark pixels from a total of 1060992 (7.11231%).
	   non-empty

EXIT STATUS

       The exit status is 0 if the image is mostly white, 1 otherwise.

SEE ALSO

       exactimage(7)

AUTHORS

       Jakub Wilk <jwilk@debian.org>
	   Wrote this manual page for the Debian system.

       http://www.exactcode.de/site/open_source/exactimage/
	   This manual page incorporates texts found on the ExactImage homepage.

COPYRIGHT

       This manual page was written for the Debian system (and may be used by others).

       Permission is granted to copy, distribute and/or modify this document under the terms of the GNU General Public License, Version 2 or (at
       your option) any later version published by the Free Software Foundation.

       On Debian systems, the complete text of the GNU General Public License can be found in /usr/share/common-licenses/GPL-2.

empty-page							    09/09/2013							     EMPTY-PAGE(1)
All times are GMT -4. The time now is 05:51 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy