Replace Numeric From File Names

ajidnair · 02-25-2008, 06:19 AM

HI All,

is there any possiblity to remove numerics from the starting of a file-name.

for eg : if i have a file named "09itdesc.txt", i want to remove the "09" from the file-name and would need it as "itdesc.txt"

I am using Fedora-8..

Thanks.........

~Destined !!!!!!

unSpawn · 02-25-2008, 06:39 AM

If it's always the first two positions for i="09itdesc.txt" you could 'echo "${i:2}"', else you could 'echo "${i//[0-9]}"'.

ajidnair · 02-26-2008, 03:50 AM

Thanks for your spontaneous reply "unSpawn", but i get no results if i run the same..

imagine i have a folder docs, inside that i have n number of files. some files will be of the case
09itdesc.txt
10itdesc1.txt
11itdesc2.txt

i would like to relpace "09itdesc.txt" to "itdesc.txt"
Similarly,

10itdesc1.txt => "itdesc1.txt"
11itdesc2.txt => "itdesc2.txt"

i would like to replace the filenames replacing the leading numerics..

Thnks ,
~Destined

Quote:

Originally Posted by unSpawn

If it's always the first two positions for i="09itdesc.txt" you could 'echo "${i:2}"', else you could 'echo "${i//[0-9]}"'.

jschiwal · 02-26-2008, 04:26 AM

It may make more sense to move the digits to the end of the filename:

Code:

for file in *itdesc.txt; do number=$(echo "$file" | sed "s/^\([[:digit:]][[:digit:]]*\)\([[:alpha:]]*\)/\2\1/"); echo $number; done
itdesc01.txt
itdesc02.txt
itdesc03.txt
itdesc04.txt
itdesc05.txt
itdesc06.txt
itdesc07.txt
itdesc08.txt
itdesc09.txt
itdesc10.txt
itdesc11.txt

If this looks OK change echo "${number}" to "mv "${file}" "${number}".

Another option is to use ls *itdesc* | cat -n to produce a list of matching filenames preceded by an ordinal number.

Code:

     1  01itdesc.txt
     2  02itdesc.txt
     3  03itdesc.txt
     4  04itdesc.txt
     5  05itdesc.txt
     6  07itdesc.txt
     7  09itdesc.txt
     8  10itdesc.txt
     9  11itdesc.txt
    10  12itdesc.txt
    11  13itdesc.txt

Look at what characters are used to separate the fields:
ls *itdesc* | cat -n | od -c

Code:

0000000                       1  \t   0   1   i   t   d   e   s   c   .
0000020   t   x   t  \n                       2  \t   0   2   i   t   d
0000040   e   s   c   .   t   x   t  \n                       3  \t   0
...

Note the use of spaces and tabs.
You may want to do this in steps to make it easier to test as you go along, and come up with a sed command the produces a rename script which you can run to perform the renaming. This makes it easier to develop the sed command.

Code:

ls *itdesc* | cat -n >temp
sed 's/^ *\([[:digit:]][[:digit:]]*\)\t\([[:digit:]][[:digit:]]\)\([[:alpha:]]*\)\.\([[:alpha:]]*\)/mv \2\3.\4 \3\1.\4/' temp >renamescript
chmod +x renamescript
rm temp
./renamescript
rm renamescript

H_TeXMeX_H · 02-26-2008, 04:59 AM

This strips off the first two characters of the name of all .txt files in a directory:

Code:

for i in *.txt
  do mv $i $(echo $i | cut -c 1-2 --complement)
done

jschiwal · 02-26-2008, 07:38 PM

Quote:

Originally Posted by H_TeXMeX_H

This strips off the first two characters of the name of all .txt files in a directory:

Code:

for i in *.txt
  do mv $i $(echo $i | cut -c 1-2 --complement)
done

Stripping off the first two characters would give rename all of the files in turn to the same name.
"${i#[0-9][0-9]}" would strip them off as well. "${i##*[0-9]}" will strip off any number of digits provided the text part doesn't contain any digits as well.

H_TeXMeX_H · 02-27-2008, 11:38 AM

Quote:

Originally Posted by jschiwal

Stripping off the first two characters would give rename all of the files in turn to the same name.

In this case:

Quote:

Originally Posted by ajidnair

imagine i have a folder docs, inside that i have n number of files. some files will be of the case
09itdesc.txt
10itdesc1.txt
11itdesc2.txt

i would like to relpace "09itdesc.txt" to "itdesc.txt"
Similarly,

10itdesc1.txt => "itdesc1.txt"
11itdesc2.txt => "itdesc2.txt"

i would like to replace the filenames replacing the leading numerics..

the files would not be renamed the same because they have two sets of numerals: ##itdesc#.txt => itdesc#.txt

But in other cases, yes. However, since the author has this particular case, my solution would work and is perhaps easiest to understand.

ajidnair · 02-28-2008, 03:00 AM

THanks a lot , it is working well.

~Destined,

P Please don't print this unless you really need to - this will preserve trees on planet earth.

jschiwal · 02-28-2008, 10:58 PM

H_TexMexH:

You are right. I either didn't notice the trailing digit or didn't take them as being literal but rather a way of generalizing the order in the directory listing.