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How do I rename hundreds of files at once?

Dave, I'm in a bit of a pickle. Like you, I'm an author, and as I wrap up my latest book project, the development editor sent me a note saying that all the figures I've submitted, all 217 of them, are incorrectly named and need to be fixed. Augh! The naming scheme I'm using is FIGxxyy.TIF where xx is the chapter number and yy is the figure number. To make it a bit more complex, sometimes I use a three digit figure number and other times I use a two digit value. I need all the files to be called xxFIGyyy.TIF. How do I do that without going crazy?

Dave's Answer:

I can relate to your pain! I find it amazing that it's usually at least half way through a book that a development editor tells me that I've been using the wrong naming scheme for the chapters or figures all along. The chapters aren't too bad, there are usually only 15-25 in a book total, but figures, well, I can have hundreds of 'em too.

To solve your problem, I noticed that you have a nice, regular pattern that you're using and that creating the new file names is purely dependent on being able to extract the specific information from the old file names.

This is where the Linux (and Mac OS X) cut command is a great tool. To extract just the third and fourth characters, for example: cut -c3-4 works just fine.

The basic logic of this solution then is to, in a loop, extract the chapter and figure numbers from the existing filename, normalize the figure number to three digits, then create a new filename by putting those informational items in a different order. Make sense?

Here's my short little script to do the job:

#!/bin/sh

for name in *TIF
do
  chap="$(echo $name | cut -c3-4)"
  fig="$(echo $name | cut -c5- | cut -d. -f1)"
  if [ $(echo $fig | wc -c) -eq 3 ] ; then
    fig="0$fig"
  fi
  # change the following 'mv' to a 'cp' for insurance
  mv $name "${chap}FIG${fig}.TIF"
done

exit 0

As you can see here, the chapter number is extracted by pulling out the third and fourth characters, and the figure number is extracted by discarding the first four characters of the filename, then grabbing everything up to, but not including, the '.' separator.

The wc invocation is a lazy way to figure out how many characters are in the figure value $fig (including a carriage return added by the echo statement). If it's three, that is, two plus the carriage return, then simple preface an additional zero to normalize them all to three character figure values.

Finally, the new filename is built with ${chap}FIG${fig}.TIF, where the curly braces are required to clearly delimit variables names versus characters to actually include in the filename itself.

Save this script to a text file while in an xterm, or the Mac Terminal application, then, presuming you named it fixnames, run it with: sh fixnames in the directory that contains your existing figures. Within just a second or two all the files should be renamed properly and you should be good to go. Good luck!


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Reader Comments To Date: 9

Navid Azimi said, on December 29, 2004 6:22 PM:

Great. Thanks. But do you have any input on accomplishing this on the Windows platform?

Dave Taylor said, on December 30, 2004 3:09 PM:

I haven't used any Windows app that makes bulk renaming easier, but a quick check at Download.com suggests that there are some possibilities worth exploring:

Rename It:
http://www.download.com/Rename-It/3000-2248_4-10148114.htm
File and MP3 Renamer 2004:
http://www.download.com/File-and-MP3-Renamer-2004/3000-2248_4-10316856.html
A.F.5 Rename your files:
http://www.download.com/A-F-5-Rename-your-files/3000-2248_4-10135890.html
Renamer 5.0:
http://www.download.com/Renamer/3000-2248_4-10341158.html
File Monkey:
http://www.download.com/FileMonkey/3000-2248_4-10267483.html

Hope that one of those helps!

Lazy Dog said, on January 14, 2005 5:23 AM:

I recently downloaded Lupas Rename which was mentioned in Fred Langa's newsletter. I have not used it yet, but it offers a lot of options.

http://www.azheavymetal.com/~lupasrename/lupasrename.php

Jonathan said, on July 5, 2006 6:54 PM:

Dave,

Thanks for the great scripts/website. I love 101 Wicked Cool Shell Scripts. I just wanted to add my two cents to this discussion for anybody searching the web for this solution. I created a Workflow in Automator to accomplish the same thing. Just choose Finder from the Automator library and use the Action Rename Finder Items. It works like a champ.

Jonathan

Tips said, on September 6, 2006 3:04 PM:

You might be able to get away with a variation of something like this::
rename -n 's/FIG(\d{2})(\d{2,3})\.TIF$/$1FIG$2\.TIF/' *.TIF

To bulk rename files on Windows, install Cygwin and/or Perl.

Tips said, on September 6, 2006 3:07 PM:

Sorry, that last comment should have said:
rename -v 's/FIG(\d{2})(\d{2,3})\.TIF$/$1FIG$2\.TIF/' *.TIF

ruchi said, on May 11, 2007 1:09 PM:

Your suggestions are really helpful.
Thank you,

siva said, on December 9, 2009 11:17 PM:

hai i have a no.of files like 'Billing_TXT_99999999_'
i want to change 'Billing_TXT_8676C_' how to rename no of files

John MacAulay said, on September 26, 2011 2:46 PM:

Hi, Dave -

Your site's a great resource - thank you. In your solution, the 'if' statement can be ditched completely by forcing the shell to treat the fig variable as a 3-digit integer with leading zeroes. Insert this line before the for loop:

typeset -Z3 fig

I'm a bit perplexed about the main body of your solution, though: the original poster said that his figure naming scheme was FIGxxyy.TIF, so shouldn't your lines read:

chap="$(echo $name | cut -c4-5)"
fig="$(echo $name | cut -c6- | cut -d. -f1)"

Or am I missing something?

Cheers,

John

Starbucks coffee cup I do have a lot to say, and questions of my own for that matter, but first I'd like to say thank you, Dave, for all your helpful information by buying you a cup of coffee!

I do have a comment, now that you mention it!











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