Sorting text tabular type data

[Alan Jackson]

On Mon, 02 Sep 2002 15:58:12 -0700 (PDT)
"stayler" <stayler at xmtservices.net> wrote:

> Here is a small example of one of the files.
> 
> K7ICW         SINGLE-OP ALL HIGH           NV    13125    
> K7XC          MULTI-LIMITED                NV    1856     
> KC6UCN        MULTI-LIMITED                NV    8477     
> N6MI          ROVER                        NV    3968     
> N7LQ          MULTI-UNLIMITED ALL HIGH     NV    82128    
> N7ROJ         ROVER                        NV    7722     
> NW7O          ROVER                        NV    2847     
> W7PW/R        ROVER                        NV    12       
> WB6YIY        SINGLE-OP ALL LOW            NV    1020
> 

Years ago I would have used awk, or a chain of sed, sort, awk, whatever.
But now I do almost all that stuff in perl.

Here are some quick examples ...

I'd start by putting in the new delimiter by using sed, since that
second field has those ugly embedded blanks.

cat inputfile | sed 's/  */,/' | sed 's/ *NV */,NV,/' > delimitedfile
                       ^^ note 2 blanks

Let's count the number of distinct things based on the second field sorted
from most to least...

	#!/usr/bin/perl -w
	use strict;
	my %hash;

	while (<>){
		chomp;
		my @line = split(',');
		$hash{$line[1]}++;
	}
	foreach (sort {$hash{$b}<=>$hash{$a}} keys %hash) {
		print "$_ : $hash{$_}\n";
	}

make a pretty list sorted by the first field...

	#!/usr/bin/perl -w
	use strict;
	my @data = <>;
	#	now use the Schwartzian transform to sort it and print it

	print map {$_->[1]}
		  sort {$a->[0] cmp $b->[0]}
		  map {[(split(','))[0], sprintf("%-8s %-30s %2s %-10s",split(','))]}
		  @data;
-- 
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| Alan K. Jackson            | To see a World in a Grain of Sand      |
| alan at ajackson.org          | And a Heaven in a Wild Flower,         |
| www.ajackson.org           | Hold Infinity in the palm of your hand |
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