Yes, you can, but you will have to extend RapidMiner with a custom extension and write your own operators (which probably inherits from the core k-Means operator). There is a white paper available in our market place which explains how you can extend RapidMiner.
Answers
please have a look at this thread: http://rapid-i.com/rapidforum/index.php/topic,4630.0.html
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Best,
Marius
Best,
Marius