@array = (1,2,50,40);
$x1 = 60; #linkes ende, horizontal
$y1 = 120; #linkes ende, vertikal

$x2 = 90; #rechtes ende, horizontal
$y2 = 100; # rechtes ende, vertikal

for (@array) {
   $y2 = $_;
   $y1+9;
   $im->line($x1, $y1, $_, $y2, $linienfarbe);
   $x1 = $_;
}