Help deleting leading zeros in a file


Login or Register for Dates, Times and to Reply

 
Thread Tools Search this Thread
Top Forums Shell Programming and Scripting Help deleting leading zeros in a file
# 1  
Help deleting leading zeros in a file

I have a list of numbers extracted and need to delete the leading zeros from them, but when i do so, the command I am using also deletes numbers that end in Zero as well. eg 10, 20, 30, etc

this is part of a larger script and the only way I can think of is to try and detect the 10,20 30 etc in the first part of a if statement then deal with the remainder but that i think is quite messy as there may be many of them

Ideas?

My input to check is like this file below and trying to process with this code snipopet
Code:
file="leadingzero.txt"     # input filename
while read line 
    do
        wardevent=${line##*[!1-9]}                     # remove leading Zero from the line
echo $wardevent
done <"$file"

File:
Code:
001
002
003
004
005
006
007
008
009
010
011
012
019
020
021

Thanks
Ken

Last edited by Scott; 09-26-2013 at 09:58 AM.. Reason: Removed attachment; not necessary for such a small file
# 2  
Input file
Code:
 $ cat file
001
002
003
004
005
006
007
008
009
010
011
012
019
020
021

What is your expected output..?

this one?

Code:
 $ awk '{$1+=0}1' file
1
2
3
4
5
6
7
8
9
10
11
12
19
20
21

or this one....?

Code:
 awk '{sub(/^0/,"")}1' file
01
02
03
04
05
06
07
08
09
10
11
12
19
20
21

Always give your input and desired output.
# 3  
Sorry for that and thanks
Yes i would like the output without the leading zeros as per this
Code:
$ awk '{$1+=0}1' file

Is there a way to do it using string processing rather than calling awk?
Reason being as the section of the file is only a selection from a much larger line that is processed as part of a much larger string. The rest of the code pulls out the numbers and then I need to stip the leading zeros before putting them in an array.

I only included the extracted part to avoid confusion with the rest of the code.

Ken

Last edited by Scrutinizer; 09-24-2013 at 04:08 PM.. Reason: code tags
# 4  
How large is the file overall, i.e. number of records?

You could shell script it like this:-
Code:
#!/bin/ksh

typeset -i col1                     # Define as integer

while read col1 rest
do
   echo "$col1 $rest"
done < input_file  > output_file

The run time may get long if the file is large though and you will get errors if any of the values in column1 are not numeric.

Does that work as a quick hit?

Perhaps you could do something with sed or awk to strip leading zeros if the file is bigger and the alapse time of the above code is not acceptable.



I hope that this helps

Robin
Liverpool/Blackburn
UK
# 5  
also


Code:
while read line 
    do
        wardevent=$(expr $line + 0)                     # remove leading Zero from the line
echo $wardevent
done<file

This User Gave Thanks to pamu For This Post:
# 6  
Dear pamu,
How does your code react with the following input? :-
Code:
0001
0002 123
0003 Hello

I regret that I get syntax errors for lines 2 & 3.



Robin
This User Gave Thanks to rbatte1 For This Post:
# 7  
Quote:
Originally Posted by pamu
also


Code:
while read line 
    do
        wardevent=$(expr $line + 0)                     # remove leading Zero from the line
echo $wardevent
done<file

Awesome thank you very much that is exactly what I need to achieveSmilie

Thanks
Ken
Login or Register for Dates, Times and to Reply

Previous Thread | Next Thread
Thread Tools Search this Thread
Search this Thread:
Advanced Search

Test Your Knowledge in Computers #259
Difficulty: Easy
Steve Jobs was born in San Francisco, California, and put up for adoption.
True or False?

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

Ho to remove leading zeros from a csv file which is sent from a UNIX script

Hi All, I am using a informatica job to create a csv file and a unix script the mail the generated file.Everything is working fine but I am not seeing leading zeros in the csv file sent in the mail.These zeros were present when the .csv file was generated by informatica procees. Is there any... (11 Replies)
Discussion started by: karthik adiga
11 Replies

2. Shell Programming and Scripting

Adding Leading Zeros for date in a file

Hello, I have a pipe separated file with two major lines. One is header and another is detail line. Header starts with H and Detail start with D. Sample Content: H|123456|Joes Watson|UK|4/5/2016|12/5/2016|3456|HC|NW|||||| D|123456|Joes... (13 Replies)
Discussion started by: Mannu2525
13 Replies

3. Shell Programming and Scripting

Fixed with file- removing leading zeros and adding the space

Hi All, i have a fixed width file , where each line is 3200 length. File: 1ABC 1111 2222 3333 000012341 1001 2ABC 1111 2222 3333 000012342 1002 3ABC 1111 2222 3333 000112343 1003 1DEF 5555 4444 9696 000012344 1004 2DEF 5555 2323 8686 000012345 1005 3DEF 5555 1212 7676 000012346 1006 ... (1 Reply)
Discussion started by: mechvijays
1 Replies

4. Shell Programming and Scripting

Numbers with leading zeros

Hi, i have a variable which conatins values like 00001,0003,00067,00459. I want to use the values one by one and in the same form as they are like 00001,0003,00067,00459. Also can anyone tell me how to increment those numbers by 1,keeping the format as same like 00002,0004,00068,00460.... (5 Replies)
Discussion started by: arijitsaha
5 Replies

5. UNIX for Dummies Questions & Answers

Add leading zeros to columns in a file

Hello Gurus, Quick question. I have a file with the following records: A~000000000000518000~SLP ~99991231~20090701~88.50~USD~CS~ A~000000000000518000~SLP ~99991231~20090701~102.00~USD~CS~ A~000000000000772000~SLP ~99991231~20100701~118.08~USD~CS~ I wold like to do the following: 1. Add... (1 Reply)
Discussion started by: chumsky
1 Replies

6. Shell Programming and Scripting

Help with adding leading zeros to a filename

Hi i need help in adding leading zero to filenames e.g file name in my folder are 1_234sd.txt 23_234sd.txt the output i need is 001_234sd.txt 023_234sd.txt can i do this shell scripting please help (2 Replies)
Discussion started by: rsmpk
2 Replies

7. Shell Programming and Scripting

Removing leading zeros from a variable

How do I remove or add leading zeroa from a variable. To make variable 10 characters long when adding zeros. (6 Replies)
Discussion started by: toshidas2000
6 Replies

8. Shell Programming and Scripting

truncating leading zeros of a column in a file

Hi I have a file in which I have 5 columns which are delimited by “|” as shown ABC|12|YAK|METRIC|000000019.5 XYZ|10|ABX|META|000000002.5 Now my requirement is to take the last column trim the leading zero’s for that column values and write back to the same file in the same... (7 Replies)
Discussion started by: nvuradi
7 Replies

9. Shell Programming and Scripting

how to retain leading zeros

Hi All, I am working with a fixed width file Forrmat. C1 Number (10,3) C2 Number (10,3) e.g. c1= 0000000100.000 c2= 0000000020.000 0000000100.0000000000020.000 I have to perform c1 - c2 . i.e. I want answer to be 0000000080.000. but I am loosing the leading zeros( only getting... (3 Replies)
Discussion started by: Manish Jha
3 Replies

10. Shell Programming and Scripting

Leading zeros

How to insert leading zeros into a left-justisfied zip code? e.g. Zip code is written as 60320 which is left-justified to make it be read as 0060320. We have to move it to right-justifiable then insert 2 leading zeros into it... ;) (1 Reply)
Discussion started by: wtofu
1 Replies