I have a hash of data on students. Each key is the student ID number. Each value contains the student's name and GPA separated by a tab character. For example: 

$students{0354} = "Fred\t3.2";
$students{4873} = "Tom\t2.9";
$students{1522} = "Susan\t4.0";

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I want to display all students sorted by the GPAs. I have the following code in place: 

foreach $key(sort GPA_sort %students)
{
     #etc
}

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but I don't know what to put in the GPA_sort subroutine.

What code should I put the GPA_sort subroutine?

Is it something like the following? 


sub GPA_sort
{
     $value_a = $students->{$a};
     $value_b = $students->{$b};
     ($name_a, $gpa_a) = split(/\t/, $value_a);
     ($name_b, $gpa_b) = split(/\t/, $value_b);

     $gpa_a <=> $gpa_b
}

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Any help would be gratefully appreciated. Thank you.

In reply to sorting by field of a tab-delimited hash value by keiusui

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