Re: Re: Unique array w/o repeated elements and still keep the original order!

That won't work how you expect it to...

Particularly, what's happening to $_? It's getting set by the while loop and then forgotten about, which is to say that you'll not process all of the lines. Oops. How about this:

while (my $line_holder = <FILE>) {
  foreach etc...
[download]

Or alternately you could check for file EOF in the while condition like so:

while (! eof(FILE)) {
   my $line_holder = <FILE>;
   foreach etc...
[download]

Either way should fix the problem...

jynx

Comment on Re: Re: Unique array w/o repeated elements and still keep the original order! Select or Download Code

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Re: Re: Re: Unique array w/o repeated elements and still keep the original order! by TexasTess (Beadle) on Aug 09, 2002 at 20:34 UTC
I'm not sure what you mean by `while (my $line_holder = <FILE>) { foreach etc...` [download] That is certainly != to what I wrote.... `while(<FILE>){ my $line_holder = $_; #GOTCHA foreach my $val(@lines){` [download] Which is something I do in tons of code I have written at work and it works fine?? Perhaps I am missing something? TexasTess "Great Spirits Often Encounter Violent Opposition From Mediocre Minds" --Albert Einstein Waiting to see just how fast this makes it to an all time negative record...and wondering if any of the downvoters think I care :-)	[reply] [d/l] [select]
Re: Re: Re: Re: Unique array w/o repeated elements and still keep the original order! by DamnDirtyApe (Curate) on Aug 09, 2002 at 20:46 UTC
That is certainly != to what I wrote.... Exactly the point. In your code, each iteration of the loop assigns the next row to `$_` (your `while` statement), then assigns the following line to `$line_holder`. The line assigned to `$_` is never handled, so it just get's "skipped." In any case, couldn't the whole process be reduced to `my %seen = () ; my @uniq_rows = grep { !$seen{$_}++ } <FILE> ;` [download] ? _______________ DamnDirtyApe Those who know that they are profound strive for clarity. Those who would like to seem profound to the crowd strive for obscurity. --Friedrich Nietzsche	[reply] [d/l] [select]
Re: Re: Re: Re: Re: Unique array w/o repeated elements and still keep the original order! by demerphq (Chancellor) on Aug 09, 2002 at 21:05 UTC
Er just a thought but any time ive written that code ive ended up changing it to `my @unique=map{chomp; $_{$_}++ ? () : $_} <FILE>;` [download] or something like it (i dont always use %_ but sometimes i do, blame ABIGAIL-II ;-) To be honest i think that in my perl career ive only used a grep a few times. map seems to be so much more useful in that it can do grep()s job, and more as well! Yves / DeMerphq --- Software Engineering is Programming when you can't. -- E. W. Dijkstra (RIP)	[reply] [d/l]
Re^6: Unique array w/o repeated elements and still keep the original order! by jynx (Priest) on Aug 09, 2002 at 21:17 UTC
Re: Re^6: Unique array w/o repeated elements and still keep the original order! by demerphq (Chancellor) on Aug 09, 2002 at 21:28 UTC


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