[H-GEN] modifying file format

[Jason Henry Parker]

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"Kris Amy" <krisamy1 at optushome.com.au> writes:

> I need to modify a file line by line and make the following changes:-
> here is the line format.
> 
> <DATA1>,<DATA2>,<DATA3>,<DATA4>
> 
> now what i need to be able to do is in DATA4 remove all spaces, ( and
> ).

perl -F, -lane'BEGIN{$"=","} $F[-1] =~ y/ ()//d; print "@F"'

That will read from files named on the command-line, or from standard
input if no filenames are given, and write to standard output.

The dissection:

-F,     split on commas
-l      chop newlines when reading, add when printing
-a      split each line into array @F, using pattern given after -F
-n      put a while(<>){ ... } around the script
-e      script follows this argument (in ''s to escape from the shell)

        [see perldoc perlrun to find out more information about these
        command-line switches.]

BEGIN{$"=","}
        start by setting $" to comma; this variable is used as an
        output separator when an array is interpolated in a
        double-quoted string.  This happens once only.

        [see perldoc perlvar, and search for $", or $LIST_SEPARATOR.]

$F[-1] =~ y/ ()//d;
        the last element of @F (where the comma-separated data values
        end up) is put through the y/// operator, which looks for
        spaces, and brackets, replacing them with nothing; the /d
        modifier deletes them, also.

        [see perldoc perlop, and search for `Transliterate'.]

print "@F"
        print the modified array; the ""s provide a double-quotish
        string, and so commas are reinserted; the -l option adds a
        newline again.

This should be enough for you to follow what's going on, and fix it if
you need to.

Cheers!
-- 
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| Mmmmm, impaled flesh!                                jasonp at uq.net.au |
|     -- Ann Burlingham                                  #soc.bi on OPN |
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