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How do i create array of arrays

by Anonymous Monk
on Jan 13, 2001 at 03:25 UTC ( #51501=categorized question: print w/replies, xml ) Need Help??
Contributed by Anonymous Monk on Jan 13, 2001 at 03:25 UTC
Q&A  > arrays


I have two de refrenced arrays like $a and $b. Now i have to create another master dereferenced array with this two arrays. Can anyone help me. Thank You, - bari

Answer: How do i create array of arrays
contributed by extremely

my $a = [ "mark", 1, 2, "three"]; #anon array my @b = ( "anon", 3, 4, "five"); #named array my $b = [@b]; #anon array from named my $c = [ $a, [@b], $b, [ "werd", 5, 6, "seven" ] ]; my @d = ( $a, $b, $c->[3] ); print "$d[2]->[3] and $c->[3][3]\n";

Does that help? () make lists, [] make anon arrays, you can nest anon arrays easily to make nested structures.

Edited by davido to correct mismatched bracket types.

Answer: How do i create array of arrays
contributed by robsv

# Create the arrays my $a = [qw(one two three four)]; my $b = [qw(red green blue)]; # Create the array of arrays my $aoa = [$a,$b]; # Print each element foreach $i (0..$#{$aoa}) { foreach $j (0..$#{$aoa->[$i]}) { print $aoa->[$i][$j] . "\n"; } }
Answer: How do i create array of arrays
contributed by Adam

my @array = ( 1..3 ); my $arrayRef = \@array; my @arrayOfArrays = ($arrayRef); print $arrayOfArrays[0]->[1];
I hope that helps.

{Editor note by davido: This approach is risky. For one thing, if @array ever changes, its changes will affect @arrayOfArrays. Thus, if you build up an array of arrays using this method inside of a loop, you could end up with multiple instances of the same @array, rather than multiple distinct and unique arrays as the contents of the @arrayOfArrays. Using my within the loop will create a new @array each time through, but better to be explicit about it rather than relying on lexical scoping which can confuse the reader later on.

Changing the second line to:

my @arrayRef = [@array];
will solve the potential problem.

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    [stevieb]: cover it all. Awesome thing is that you can dispatch ANY distribution to it (and include all revdeps if desired), and it works all the same as if I'm just testing the RPI code itself
    [stevieb]: I'm rather pleased with myself and everything I've leared along this arduous and sometimes frustrating path
    [stevieb]: Just need to implement an email plugin or something so I can get alerted remotely if the status of a build has changed from the last run
    [stevieb]: Because of the extreme complexity of the testing code itself, I implemented extensive logging so I can troubleshoot much easier by setting a high debug level.
    [stevieb]: if you're interested in the test/build backend, have a look at Test::BrewBuild.

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