How do I sort on more than one column?

Russ has asked for the wisdom of the Perl Monks concerning the following question: ⭐ (sorting)

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Re: How do I sort on more than one column?⭐ by Russ (Deacon) on Jul 23, 2000 at 23:52 UTC
The comparison operators return 0 when the operands are equal. So, using the \|\| operator, we can sort first by one column, then another (as many as we want). `@data = ( [qw(Bubba brutalski 20)], [qw(Bubba brutalski 10)], [qw(JoeBob brutalski 20)], [qw(Jethro brutalski 20)], [qw(Junior brutalski 20)], ); # Sorted by Name (Last, First) @ByName = sort {$a->[1] cmp $b->[1] \|\| $a->[0] cmp $b->[0]} @data; # Sorted by Name, then score @FullSort = sort {$a->[1] cmp $b->[1] \|\| $a->[0] cmp $b->[0] \|\| $a->[2] <=> $b->[2]} @data;` [download] In the second example above, @FullSort looks like: `( [Bubba, brutalski, 10], [Bubba, brutalski, 20], [Jethro, brutalski, 20], [JoeBob, brutalski, 20], [Junior, brutalski, 20] )` [download] because it is sorted by Last Name, then First Name, then Score. Russ	[reply] [d/l] [select]

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Re: How do I sort on more than one column?⭐
by Russ (Deacon) on Jul 23, 2000 at 23:52 UTC

@data = (
        [qw(Bubba  brutalski 20)],
        [qw(Bubba  brutalski 10)],
        [qw(JoeBob brutalski 20)],
        [qw(Jethro brutalski 20)],
        [qw(Junior brutalski 20)],
);

# Sorted by Name (Last, First)
@ByName = sort {$a->[1] cmp $b->[1] || $a->[0] cmp $b->[0]} @data;

# Sorted by Name, then score
@FullSort = sort {$a->[1] cmp $b->[1]
                  ||
                  $a->[0] cmp $b->[0]
                  ||
                  $a->[2] <=> $b->[2]} @data;
[download]

(
  [Bubba,  brutalski, 10],
  [Bubba,  brutalski, 20],
  [Jethro, brutalski, 20],
  [JoeBob, brutalski, 20],
  [Junior, brutalski, 20]
)
[download]

Russ

[reply]
[d/l]
[select]