Perhaps there are four graphs but they all occupy the same space? Or, by re-using $graph, it is over-writing the previous version?
I would consider using an array $graph and outputting a break <br> between each Stroke(). But you haven't explained what exactly goes wrong..
I'm with mlseim as well: get it working with one.
"I'm here to save your life. But if I'm going to do that, I'll need total uninanonynymity
." Me Myself & Irene
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