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Full Discussion: Detail on For loop for multiple file input and bash variable usage
Top Forums Shell Programming and Scripting Detail on For loop for multiple file input and bash variable usage Post 302781353 by Don Cragun on Saturday 16th of March 2013 09:24:56 AM
Old 03-16-2013
I don't understand what you're asking about fortran code, but getting sets of 3 files in sorted order in the shell is not hard. This doesn't do anything very useful, but may be a suitable example to show you what needs to be done to meet your requirements:
Code:
#!/bin/ksh
ls *.txt|sort -t"_" -k2n,2|while read f1 && read f2 && read f3
do      echo processing $f1, $f2, and $f3
done

Note that this won't work if any of your *.txt filenames contain whitespace characters, and will silently ignore the last one or two *.txt files if the number of *.txt files is not an integral multiple of 3. In a directory containing the files:
Code:
ABC_6.txt
B.txt
DEF_5.txt
GHI_7.txt
a.txt
abc_123.txt
bcd_987.txt
cde_456.txt
tester
z.txt

this script produces the output:
Code:
processing B.txt, a.txt, and z.txt
processing DEF_5.txt, ABC_6.txt, and GHI_7.txt
processing abc_123.txt, cde_456.txt, and bcd_987.txt

This User Gave Thanks to Don Cragun For This Post:
Akshay Hegde
 

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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)
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