Re: Grouping By A Column

rocky13

You're on the right track. You do grouping with a hash. Each time you get a row, create the entry if it doesn't exist, or add in the data:

my ($col1, $col2, $col3) = generate_data();
if (! defined $hash{$col1}) {
    $hash{$col1} = [ 0, 0 ]
}
$hash{$col1}[0] += $col2;
$hash{$col1}[1] += $col3;
[download]

...roboticus

When your only tool is a hammer, all problems look like your thumb.

Comment on Re: Grouping By A Column Download Code

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Re^2: Grouping By A Column by JavaFan (Canon) on Jan 27, 2011 at 11:35 UTC
Due to autovivification, you can half the number of lines in the snippet: `my ($col1, $col2, $col3) = generate_data(); $hash{$col1}[0] += $col2; $hash{$col1}[1] += $col3;` [download] will do.	[reply] [d/l]
Re^2: Grouping By A Column by rocky13 (Acolyte) on Jan 27, 2011 at 04:29 UTC
That clears up a lot of things. One more question. Can you read an excel file the same way you read a .txt file?	[reply]
Re^3: Grouping By A Column by GrandFather (Saint) on Jan 27, 2011 at 06:30 UTC
In a word: 'No'. But there are many Excel related modules in CPAN. A good starting point is probably Spreadsheet::ParseExcel. True laziness is hard work	[reply]