Fastest way to delete duplicates from a large filelist..... Post: 302537363

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Top Forums Shell Programming and Scripting Fastest way to delete duplicates from a large filelist..... Post 302537363 by Bashingaway on Friday 8th of July 2011 01:48:13 AM

07-08-2011

Registered User

Quote:

Originally Posted by agama

First off, it is wise to avoid 'loading' variables with cat -- in your case, with a million filenames/pathnames, you are likely to exceed the amount that can be stuffed into a variable. Something like this would allow you to do the same thing without issues:

Code:

while read filename
do
    echo $filename
done <file-list-file

That said, you are correct your approach isn't efficient. I interpreted your requirements to be that you need a list of files from 'filewithpath.txt' that are NOT listed in the duplicate list file. If that is the case, this should work for you:

Code:

sed 's!.*/!!' FileWithPath.txt | sort -u >/tmp/f1      # strip pathname and sort removing any dups
sort -u DuplicateFiles.txt >/tmp/f2                       # both files must be sorted for comm, remove dups just in case
comm -23 /tmp/f1 /tmp/f2 >ListWithoutDups.txt
rm /tmp/f1 /tmp/f2

I have always found the options to comm to be difficult to understand and have to read the man page nearly every time I use it. In this case, comm reads both files in parallel (thus they must be sorted) and keeps the records that are unique to the first file (not listed in the second file).

Thanks for this but I'm not sure it'll work for me. My original example is the problem, sorry.

When you strip the pathname on the first line it therefore removes where to get the file that I want to perform the process's on?

Bashingaway

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LEARN ABOUT SUSE

jpegicc

JPEGICC(1)						      General Commands Manual							JPEGICC(1)

NAME

       jpegicc - little cms ICC profile applier for JPEG.

SYNOPSIS

       jpegicc [options] input.jpg output.jpg

DESCRIPTION

       lcms is a standalone CMM engine, which deals with the color management.	It implements a fast transformation between ICC profiles.  jpegicc
       is little cms ICC profile applier for JPEG.

OPTIONS

       -b     Black point compensation.

       -c <0,1,2,3>
	      Precalculates transform. (0=Off, 1=Normal, 2=Hi-res, 3=LoRes) [defaults to 1]

       -g     Marks out-of-gamut colors on softproof.

       -h <0,1,2>
	      Show summary of options and examples.

       -i profile
	      Input profile (defaults to sRGB).

       -m <0,1,2,3>
	      SoftProof intent.

       -n     Ignore embedded profile.

       -p profile
	      Soft proof profile

       -o profile
	      Output profile (defaults to sRGB).

       -q <0..100>
	      Output JPEG quality.

       -t <0,1,2,3>
	      Intent (0=Perceptual, 1=Colorimetric, 2=Saturation, 3=Absolute).

       -v     Verbose.

EXAMPLES

       To color correct from scanner to sRGB:
	    jpegicc -iscanner.icm in.jpg out.jpg

       To convert from monitor1 to monitor2:
	    jpegicc -imon1.icm -omon2.icm in.jpg out.jpg

       To make a CMYK separation:
	    jpegicc -oprinter.icm inrgb.jpg outcmyk.jpg

       To recover sRGB from a CMYK separation:
	    jpegicc -iprinter.icm incmyk.jpg outrgb.jpg

       To convert from CIELab ITU/Fax JPEG to sRGB
	    jpegicc -iitufax.icm in.jpg out.jpg

NOTES

       For suggestions, comments, bug reports etc. send mail to info@littlecms.com.

SEE ALSO

       tifficc(1), icc2ps(1), icclink(1), icctrans(1), wtpt(1)

AUTHOR

       This manual page was written by Shiju p. Nair <shiju.p@gmail.com>, for the Debian project.

								September 30, 2004							JPEGICC(1)

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