On Wed, 14 Nov 2001 12:42:44 -0800, ehughes wrote:
>I have some simple files to parse. The data looks like this:
>
>54 6342059
>80 6342059
>31 6158566
....
>The first column is an activity code and the second column is a client id
>number.
>
>Here is my task. I need to find the number of unique individuals that
>participated in each activity. Now the boring, tedious way would be to write
>something like this:
>
>for my $row {
> $act_54{$row1} if (column1 == "54");
> $act_80{$row1} if (column1 == "80");
> $act_90{$row1} if (column1 == "90");
>}
>print scalar (keys %act_54);
>print scalar (keys %act_80);
>print scalar (keys %act_90);
This looks like fake code to me.
>Surely, there is something that will capture the data a little easier than
>defining a variable for each activity. There are more than 30 activities.
Why don't you use a hash of hashes? Assuming that $activity can be
something like "54" and $client like "6342059", this may do:
while(<>) {
chomp;
my($activity, $client) = split /\s+/;
$act{$activity}{$client}++
}
local($\, $,) = ("\n", " ");
foreach my $activity (sort { $a <=> $b} keys %act) {
print "$activity:", sort keys %{$act{$activity}};
}
--
Bart.
