in reply to Why does it return 0?

From the Perl Cookbook:

sub dec2bin {
    my $str = unpack("B32", pack("N", shift));
    $str =~ s/^0+(?=\d)//;   # otherwise you'll get leading zeros
    return $str;
}

sub bin2dec {
    return unpack("N", pack("B32", substr("0" x 32 . shift, -32)));
}

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And your code is always returning zero because you declare $binnumb inside of the subroutine, thus resetting it every time it is called. At the last execution of the routine, $inNumb % 2 is zero.

Cheers,
Ovid

New address of my CGI Course.

Replies are listed 'Best First'.
Re: Re: Why does it return 0?
by mAineAc (Novice) on Feb 05, 2004 at 02:13 UTC
    Thank you Ovid, I was actually going to use this but I have to actually do it manually.
[reply]
      If you want to know how conversion of numbers to a string works, try this: 
      $num = 1234567;
$result = "";
$base = 2;
do {
    use integer;
    my $digit = $num % $base;
    substr($result, 0, 0) = $digit; # for any number < 10
    $num /= $base;
} while $num;
print $result;

      [download]
      If you like fixed width output, add enough zeros to the front, afterwards: 
      substr($result, 0, 0) = "0" while length($result) < 32;

      [download]

      If you want to play with $base > 10, for example hexadecimal , try: 

      $num = 1234567;
$base = 16;
$result = "";
my @digit = (0 .. 9, 'A' .. 'Z');
do {
    use integer;
    my $digit = $num % $base;
    substr($result, 0, 0) = $digit[$digit]; # for base up to 36
    $num /= $base;
} while $num;
print $result;

      [download]

      Note that the do { ... } while $num; construct makes the loop execute at least once, so you get a proper result for zero.

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