I'm trying to create a circuit from a text file. The format is that wire is represented as a '.' and a capacitor is represented by a number (0-9). (So far this is all that is supported.) The first element must be a battery, and the positive lead goes to the right, the negative goes down. In reading in the file, I transfer it to an array. However, when I later try to access the array via $Circ->[$i][$j], I cannot test this for equality -- I print out the value of @{$Circ->[$i][$j]} and it is '.', but when I ask if @{$Circ->[$i][$j]} eq '.' (or == '.' or =~ /\./) I get a negative. Here is a snippet. 
# read in file, make circuit ...

use Data::Dumper;

#               012345678901  <--(i)-->
#            0  B+.....1....
#    |       1  -          .
#   (j)      2  .          .
#    |       3  .          .
#            4  .........2..
#    =======================
#    C1:5 (for 5 uF)
#    C2:6

open (CIRC, "circ.txt");

$i = 0; $j = 0;
while (<CIRC>) { # put elements of circuit into m-d array
    last if $_ =~ /=+/;
    chomp;
    $i = 0;
    for $char (split //, $_) { push @{$Circ->[$i++][$j]}, $char }
    $j++;
}

$i = 1; $j = 0;

while (1) {
    # count caps, make sure > 1

    $on_i = $i; $on_j = $j;

    # make conditions for going up, dwn, lft, rt...
    if ($j-1 > 0) { LookAt ($i,$j-1) } # look up
    if ($j+1 < scalar @{$Circ->[$i]}-1) { LookAt ($i,$j+1) }
              # look down
    if ($i-1 > 0) { LookAt ($i-1,$j) } # look left
    if ($i+1 < scalar @$Circ-1) { LookAt ($i+1,$j) }
               # look up

}


sub LookAt {
    $l_i = $_[0];
    $l_j = $_[1];

    if (@{$Circ->[$l_i][$l_j]} eq '.') { print "i'm here" }
}

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In reply to Array equality woes by dimmesdale

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