⭐ in reply to How to sort array by columns maintaining the rows? (for C style arrays)

the following code shows how to sort this data structure by any of its three columns. 
@data = (
    [qw(marek brutalski 20)],
    [qw(zenia markownikowa 10)],
    [qw(teresa parufkowa 90)],
    [qw(bogumila pierdawa 40)],
    [qw(genowefa tempawa 50)],
);

# Sort by first name
@sorted_by_first = sort { $a->[0] cmp $b->[0] } @data;

# Sort by last name
@sorted_by_last = sort { $a->[1] cmp $b->[1] } @data;

# Sort by score
@sorted_by_score = sort { $a->[2] <=> $b->[2] } @data;

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notice that the sorts on columns 0 and 1, the names, are performed ASCIIbetically, while the sort by number is done numerically.
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RE: RE: How to sort array by columns maintaining the rows? (for C style arrays)
by Anonymous Monk on Jul 03, 2000 at 18:20 UTC
    First, "progressive sorting" does not work as expected: Each sort step destroys the order created by the previous sorts. You need to use the || operator as described in the above answers.

    Second, to sort your line speeds, create a hash that converts the names to sortable numbers: 

    my $n=1; 
for (qw(115kbps 2Mbps 10Mbps T1)) {$order{$_}=$n++}

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    Now, you can sort line speeds. Suppose that your list @connections contains records with the line speed in the first element (index 0). Thus, 
    @result= sort {$order{$a->[0]} <=> $order{$b->[0]}} @connections;

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