in reply to Re: sorting hash by value when value is an array ref
in thread sorting hash by value when value is an array ref

foreach $homework (@homeworks)
{            
    $query = "SELECT PointValue,DueDate FROM Homework WHERE ClassID = 
+\'$courseID\' AND SectionID = \'$sectionID\'  AND InstructorID = $ins
+tructorID AND HomeworkName = \'$homework\'";
    $statementHandle = $databaseHandle -> prepare($query);
    $statementHandle -> execute();
    while(@rowArray = $statementHandle -> fetchrow_array())
            {
                $homeworkHash{$homework} = [$rowArray[0],$rowArray[1]]
+;
            }
}
# now the sorting
my @sorted = sort { $homeworkHash{$a}[1] cmp $homeworkHash{$b}[1] } ke
+ys %homeworkHash;

# I then pass the @sorted to a template under the name homeworks and i
+n the template I use this to print out the hash.

[% FOREACH key IN homeworks %]
        <th valign="bottom" class="Homework"><span id="points">[% key 
+%]</span><br>[% homework.$key.0 %]<br>[% homework.$key.1 %]</th>
        [% END %]

[download]
This doesn't print out a thing in the template. It is as if the @sorted in empty.

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Re^3: sorting hash by value when value is an array ref
by jdporter (Paladin) on Nov 16, 2004 at 03:06 UTC
    Well, I don't know what all that non-Perl junk is... but I'm inclined to guess that [% FOREACH key IN homeworks %] is iterating over the keys in some other order, and that you're throwing away the result of the sort you so carefully set up. Do you know a way to set the key for iteration based on the contents of @sorted ?
[reply]
[d/l]
[select]
      I pass the @sorted to the template( it is perl, it's the Template-Toolkit). I pass it like this. 
      my $vars = {
            homework => \%homeworkHash,
            homeworks => \@sorted,
        };
my $tt = Template->new({
                INCLUDE_PATH => "/inetpub/wwwroot/lib",
                WRAPPER => 'wrapperInstructor.htm',
                });
                
            $tt->process('ClassGrades.htm', $vars)||die $tt->error();

      [download]
      The Template then uses the array named homeworks which is identical to @sorted in the perl script. The [% FOREACH key IN homeworks %] just iterates through the array and prints inserts each element into the hash to get the value.
[reply]
[d/l]
[select]
        If I pass a list of the keys to the template, everything prints out fine. So I'm assuming there must be a problem in my perl script.
[reply]

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