in reply to Efficient Comparison of Array elements

You want the intersection and the difference of two sets.

This is in the FAQ.

How do I compute the difference of two arrays? How do I compute the intersection of two arrays?.

By the way, your syntax for creating your arrays:

my @one = [1,2,3,4];
my @two = [2,4,6,8];

[download]

is wrong. It should be either:

my @one = (1,2,3,4);
my @two = (2,4,6,8);

[download]

or

my $one = [1,2,3,4];
my $two = [2,4,6,8];

[download]
--
<http://www.dave.org.uk>

"The first rule of Perl club is you do not talk about Perl club."
-- Chip Salzenberg

Replies are listed 'Best First'.
Re: Re: Efficient Comparison of Array elements
by aging acolyte (Pilgrim) on Jan 08, 2003 at 16:29 UTC
    davorg

    Thanks a lot, that is roughly what I want. But a couple of follow ups:

    Is this efficient/practical if both arrays get to sizes of 10K elements?

    The array generated for difference contains elements from both arrays. I wanted those unique to @one AND those unique to @two. Again I can do this by comparing @difference with @one and @difference with @two. But I am running the same code three times. Is it practical?

    A.A.

    BTW - as for the syntax thing - a good general rule for SOPW would be "first engage brain then type...."

[reply]

In Section Seekers of Perl Wisdom