Perl array unique elements

Question

I have a perl array like below and I have to extract the unique elements of this array. Is there an easy way to do this ?

Perl> print(Dumper(@uncurled_data))
$VAR1 = '100 200';
$VAR2 = '100 200';
$VAR3 = '300 400';
$VAR4 = '100 200';
$VAR5 = '100 200';
$VAR6 = '300 400';
$VAR7 = '300 400';
$VAR8 = '300 400';

When I do this, keys { map { (split /\ /, $_)[0] => 1 } @uncurled_data }, I'll have to do it twice ie, once for each element in the array. Is there any one/liner or simple way to do this ?

Desired output array with 4 elements 100, 200, 300, 400

ikegami · Accepted Answer · 2019-12-23 13:29:27Z

3

First create a list of what you want to make unique,

map { split } @uncurled_data

Then use the standard ways of finding the unique items.

use List::Util qw( uniq );
my @uniq = uniq map { split } @uncurled_data;

or

my %seen;
my @uniq = grep { !$seen{$_}++ } map { split } @uncurled_data;

edited Dec 23, 2019 at 13:29

answered Dec 23, 2019 at 13:25

ikegami

391k17 gold badges290 silver badges554 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Vinodini Natrajan Over a year ago

Required output array with 4 elements 100, 200, 300, 400

Andrey · Accepted Answer · 2019-12-23 21:28:58Z

0

You can also do it this way:

my @uniq = sort keys %{+{map {$_ => 1;} map { split } @uncurled_data}};

answered Dec 23, 2019 at 21:28

Andrey

1,8281 gold badge17 silver badges28 bronze badges

Collectives™ on Stack Overflow

Perl array unique elements

2 Answers 2

1 Comment

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

1 Comment

Comments

Your Answer

Sign up or log in

Post as a guest

Related