On 6/5/07, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote:
snip
how do i declare loop and print a 4 dim array
snip
Arrays in Perl are all one dimensional, but multiple dimensions can be
faked with references. Given an "multidimensional" array @a, you
would access the first level with $a[0]. The value at this level
would be an arrayref. You could then dereference and index into that
array like this $a[0]->[0]. This is clunky so Perl lets you remove
the arrow operator between the [] operators like this $a[0][0]. The
value at this level is also an arrayref, so we can say $a[0][0][0] and
so on until you get to a level that is not an array ref (in a four
dimensional array it would be $a[0][0][0][0]). Now, since each level
is either an array or an arrayref we can iterate over each level like
this
#!/usr/bin/perl
use strict;
use warnings;
my @a = (
[
[
[ "0,0,0,0", "0,0,0,1" ],
[ "0,0,1,0", "0,0,1,1" ],
[ "0,0,2,0", "0,0,2,1" ],
[ "0,0,3,0", "0,0,3,1" ],
[ "0,0,4,0", "0,0,4,1" ],
],
[
[ "0,1,0,0", "0,1,0,1" ],
[ "0,1,1,0", "0,1,1,1" ],
],
],
[
[
[ "1,0,0,0", "1,0,0,1" ],
],
[
[ "1,1,0,0", "1,1,0,1" ],
]
]
);
for my $aref (@a) {
for my $aref (@$aref) {
for my $aref (@$aref) {
for my $item (@$aref) {
print "$item\n";
}
}
}
}
#or
for my $i (0 .. $#a) {
for my $j (0 .. $#{$a[$i]}) {
for my $k (0 .. $#{$a[$i][$j]}) {
for my $l (0 .. $#{$a[$i][$j][$k]}) {
print "position [$i][$j][$k][$l] is
$a[$i][$j][$k][$l]\n";
}
}
}
}
--
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
http://learn.perl.org/
