my @lines = readline or exit;
chomp for @lines;
-my @values = map { s/^\h*(-?[0-9]*)// and $1 } @lines;
+my @values = map { s/^\h* ( -? [0-9]* (?:\.[0-9]+)? )//x and $1 } @lines;
my @order = sort { $b <=> $a } @values;
my $maxval = max $order[0], -$order[-1];
-my $lenval = 1 + ($order[-1] < 0) + int log($maxval || 1) / log 10; # max string length
+my $lenval = max map { length } @order;
my $len = 1 + max map { length } @lines; # left padding
-my $size = ($opt{width} - $lenval - $len) / $maxval; # bar multiplication
+my $size = $maxval && ($opt{width} - $lenval - $len) / $maxval; # bar multiplication
sub orderpos { ($order[$_[0]] + $order[$_[0] + .5]) / 2 * $size }
my @barmark;