Dear all,

I am simply opening one file, reading each line, and according to the nature of the line, appending it to one of 2 or 3 files, thus 'sorting' the file into seperate files.

I can either, go through the original FILE 3 times, and each time, only write the lines of one particular nature to a file. 


foreach my $n (@natures){
open (OUT, "> $n.txt") or die "blah blah $! \n"
while(<FILE>){
 print OUT $_ if $_ =~ /$n/;
}
}

[download]
OR, I can do through FILE once, but at each line, check the nature, and append to the appropiate file: 
while(<FILE>){
foreach my $n (@natures){
if($_ =~ /$n/){
open (OUT, ">> $n.txt") or die "blah blah $! \n"
print OUT $n;
close OUT;
}
}
}

[download]
I was wondering, seeing FILE has thousands of lines, whether, reiterating through those thousands would be any quicker than opening and closing several files once for every line...

Cheers
S

In reply to Speed of opening and closing a file 1000s times by seaver

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