sharing array of arrays between threads

bebe has asked for the wisdom of the Perl Monks concerning the following question:

Hi I'm trying to share an array of arrays between threads and I have no luck with that.
I'm new to Perl, I would really appreciate all your help
here is how I'm sharing array X

my $ARRAY_SIZE = 45;
my $X = &make_shared_array();

sub make_shared_array {
my $a = &share([]);
for (my $i = 0;$i < $ARRAY_SIZE;++$i) {
my $row = &share([]);
$a->[$i] = $row;
}
return $a;
}

sub abc {
push(@{$X[$var1]}, $Var2);
}

Basically, new string in (Var2) will be pushed into array X every time this sub gets called.
After we are done writing array X, I would like to be able to compare each of these arays X[0], X[1], X[2], .... Against a one_dim array "Y"
but before I even get to compare the arrays I tried to print X[1] and it's blank :(
I'm not sure what I'm missing.
Thank you so so much for your help

sub test{
Print "@X[1]\n";
}

This is what I'm hoping to print:

X[0] = ("QWE", "RTYU" ,"IOP")
X[1] = ("QSWE", "TYU" ,"IKOP", "BVC")
X[2] = ("QE", "TYU")
X[3] = ("QSWE", "TYU" ,"IKOP", "BVC", "LMNB")
.
.
.

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Re: sharing array of arrays between threads by aitap (Curate) on Aug 10, 2012 at 07:56 UTC
One of your mistakes is that you first create `$X` which looks like it's a reference to array, but then try to print `@X[1]`, which is an element of `@X` which is different to `$X`. See this example: `$ perl -d -e 1 DB<1> $X = [ 1 .. 10 ]; # create a reference to an anonymous array DB<2> x $X # print the array by its reference 0 ARRAY(0x9a45510) 0 1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8 9 9 10 DB<3> @X = ( 2 .. 20 ); # create an array DB<4> x @X # display the array 0 2 1 3 2 4 3 5 4 6 5 7 6 8 7 9 8 10 9 11 10 12 11 13 12 14 13 15 14 16 15 17 16 18 17 19 18 20 DB<5> x @X[1] # display an element of the array 0 3 DB<6> x $X->[1] # display an element of the anonymous array by its r +eference 0 2` [download] See perlreftut for more information. Sorry if my advice was wrong.	[reply] [d/l] [select]
Re^2: sharing array of arrays between threads by bebe (Novice) on Aug 10, 2012 at 23:32 UTC
thank you so much for your help.... I've also tried the following... but I still have no luck getting this to work my @X : shared; my $var = &share([]); for (my $i=0; $i< 222; $i++){ $X[$i] = $var; } sub abc { my $Var2; .... Here the string in $Var2 gets updated everytime abc is called push(@{X[$i]}, $Var2); } thank you so much!!!	[reply] [d/l] [select]
Re^3: sharing array of arrays between threads by aitap (Curate) on Aug 11, 2012 at 08:25 UTC
How exactly this doesn't work? Did you try using Data::Dumper to print your variables inside the threads? Sorry if my advice was wrong.	[reply]
Re: sharing array of arrays between threads by kcott (Archbishop) on Aug 10, 2012 at 09:22 UTC
Firstly, take a look at the following: perlthrtut - Perl threads tutorial threads - Perl interpreter-based threads threads::shared - Perl extension for sharing data structures between threads In addition, here's a couple of points based on the code you've supplied: You should generally be using `subroutine()` instead of `&subroutine()`, i.e. no leading ampersand (`&`). See perlsub. Update: See ++BrowserUk's comment below. threads::shared has: `$var = &share([]); # Same as $var = shared_clone([]);` [download] `$a` (and `$b`, which you haven't used) are special variables used by sort and a number of other list-related functions (see List::Util and List::MoreUtils for some examples). `$a` and `$b` are described in perlvar. -- Ken	[reply] [d/l] [select]
Re^2: sharing array of arrays between threads by BrowserUk (Patriarch) on Aug 10, 2012 at 09:42 UTC
You should generally be using subroutine() instead of &subroutine(), i.e. no leading ampersand (&). See perlsub. Actually, if you read threads::shared, you'll find that his use of `&share([]);` is exactly the correct thing to do in this case. With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice. The start of some sanity?	[reply] [d/l]
Re^3: sharing array of arrays between threads by kcott (Archbishop) on Aug 10, 2012 at 10:23 UTC
++ Thanks for pointing that out. I've updated my node. -- Ken	[reply]
Re^4: sharing array of arrays between threads by bebe (Novice) on Aug 10, 2012 at 23:51 UTC
Re: sharing array of arrays between threads by rohit_raghu (Acolyte) on Aug 10, 2012 at 07:05 UTC
what is share() ? Also, $ARRAY_SIZE is defined in the main package using 'my' and won't be accessible inside the subroutine, at-least I think so. Can you post your program as is? or atleast a trial version? Rohit Raghunathan	[reply]