eventual wrote:
Hi,
Hello,
I have an array , @datas, and each element within @datas is a string
that's made up of 6 digits with spaces in between like this “1 2 3 4 5
6”, so the array look like this
@datas = ('1 2 3 4 5 6', '1 2 9 10 11 12', '1 2 3 4 5 8', '1 2 3 4 5
9' , '6 7 8 9 10 11');
Now I wish to compare each element of @datas with the rest of the
elements in @datas in such a way that if 5 of the digits match, to
take note of the matching indices, and so the script I wrote is
appended below.
However, the script below takes a long time to run if the datas at
@datas are huge( eg 30,000 elements). I then wonder is there a way to
rewrite the script so that the script can run faster.
Thanks
###### script below #######################
#!/usr/bin/perl
use strict;
my @matched_location = ();
my @datas = ('1 2 3 4 5 6', '1 2 9 10 11 12', '1 2 3 4 5 8', '1 2 3 4 5 9' , '6
7 8 9 10 11');
my $iteration_counter = -1;
foreach (@datas){
$iteration_counter++;
my $reference = $_;
my $second_iteration_counter = -1;
my $string = '';
foreach (@datas){
$second_iteration_counter++;
my @individual_digits = split / /,$_;
my $ctr = 0;
foreach(@individual_digits){
if($reference =~/^$_ | $_ | $_$/){
$ctr++;
}
}
if ($ctr>= 5){
$string = $string . "$second_iteration_counter ";
}
}
$matched_location[$iteration_counter] = $string;
}
my $ctr = -1;
foreach(@matched_location){
$ctr++;
print "Index $ctr of \@matched_location = $_\n";
}
Your program can be reduced to:
my @matched_location;
my @datas = ( '1 2 3 4 5 6', '1 2 9 10 11 12', '1 2 3 4 5 8', '1 2 3 4 5
9', '6 7 8 9 10 11' );
for my $i ( 0 .. $#datas ) {
for my $j ( 0 .. $#datas ) {
$matched_location[ $i ] .= "$j " if 5 <= grep $datas[ $i ] =~
/(?:^|(?<= ))$_(?= |$)/, split ' ', $datas[ $j ]
}
}
print map "Index $_ of \@matched_location = $matched_location[$_]\n", 0
.. $#matched_location;
You should benchmark it to see if it is any faster than your original code.
John
--
Any intelligent fool can make things bigger and
more complex... It takes a touch of genius -
and a lot of courage to move in the opposite
direction. -- Albert Einstein
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