niall_heavey
Novice
Jul 14, 2010, 7:27 AM
Post #1 of 22
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Hi all, i've been trying to find this on another forum but no joy so thought i'd see what else is out there.
I'm quite new to perl so bare with me!
I have got a csv file which I am reading in, there is a lot of repeated information in columns 3 and 5. I was trying to see which is the most common entry from both of these columns.
I then wanted to sort it in numerical order.
At the moment I have my list of the number of entries for each value from both columns but now I am trying to sort it numerically....... (If possible just the top 5 or 10 entries as there are hundreds!)
I have searched many tutorial websites and have seen the same piece of code to do this, but for some reason it does not work for me.
#!/usr/bin/perl
#use strict;
#use warnings;
#use Text::CSV;
my $dat_file = 'file.csv';
my $index = {};
my $index_test = {};
@data =('col1', 'col2', 'col3', 'col4', 'col5', 'col6', 'col7');
open (F, $dat_file), print "File Opened\n\n" || die ("Could not open file");
while ($line = <F>)
{
($data1,$data2,$data3,$data4,$data5,$data6) = split ',', $line;
if (exists($index{$data3}))
{
$index->{ $data3 } = 1;
}
else
{
$index->{ $data3 } =$index->{ $data3 }+1 ;
}
if (exists($index{$data5}))
{
$index->{ $data5 } = 1;
}
else
{
$index->{ $data5 } = $index->{ $data5 }+1 ;
}
}
foreach $value (sort {$index{$a} cmp $index{$b} }
keys %index)
{
print "$value => $index{$value}\n";
}
close (F);
print"\n";
This is the code I have, pretty sure the problem is somewhere in the
foreach $value (sort {$index{$a} cmp $index{$b} }
section near the end.
I am not getting an error but am just getting "File Opened " output to the screen!
Can anyone see where my problem might be?
Thanks,
N
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