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Full Discussion: Understanding sed
Top Forums Shell Programming and Scripting Understanding sed Post 302774017 by panyam on Friday 1st of March 2013 04:16:52 AM
Old 03-01-2013
Hi Scrutinizer,

Thanks for the reply. I got your second correctly.

Your first answer is slightly confusing me!..

Let's say the sample input is:

Code:
abcd:x:panyam:panyam:Panyam:512

echo "abcd:x:panyam:panyam:Panyam:512" | sed 's/^\([^:]*\):[^:]:/\1::/' gives me:

abcd::panyam:panyam:Panyam:512

\([^:]*\) matches : abcd
[^:] matches :x

\1 : prints only "abcd"..

Now, how the rest of the line is coming in output as it is? I mean
Code:
"panyam:panyam:Panyam:512"

.

Is it because sed prints the non matching patterns as it is?

Is my understanding correct?
 

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fst-mor(1)							      fst-mor								fst-mor(1)

NAME
fst-mor - Interactive morphological analyser and generator SYNOPSIS
fst-mor [options] file OPTIONS
-n Print multi-character symbols without the enclosing angle brackets. -h Print usage information. DESCRIPTION
fst-mor is an interactive morphological analyser and generator. The argument is the name of a file which was generated by fst-compiler (without using option -c). fst-mor reads the transducer which is stored in the argument file and prompts the user for input. Each input line is processed until the user enters "q" which ends the program. fst-mor has two modes, an analysis mode (default) and a generation mode. Entering an empty input line switches between the two modes. In order to explain what the program does in generation and analysis, consider the following transducer: a b:x c:<> d In generation mode, the program will print "axd" if the user enters "abcd" and "no result" otherwise. In other words, the program maps the left symbols to the right symbols of the transducer. In analysis mode, the program will print "abcd" if the user enters "axd" and "no result" otherwise. BUGS
No bugs are known so far. SEE ALSO
fst-compiler AUTHOR
Helmut Schmid, Institute for Computational Linguistics, University of Stuttgart, Email: schmid@ims.uni-stuttgart.de, This software is available under the GNU Public License. February 2002 fst-mor(1)
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