Figured this out about ten minutes after I posted the message, and much simpler than I thought it would be.
I used the SumFloatFunction (which extends MultiFloatFunction) as a starting point and was able to achieve what I was going for for my test; a simple string length function that returns the length of the specified fields after concatenation very nice being able to create custom functions. now on to creating custom functions that handle multiValued data types -- View this message in context: http://lucene.472066.n3.nabble.com/how-do-I-create-custom-function-that-uses-multiple-ValuesSources-tp1402645p1403070.html Sent from the Solr - User mailing list archive at Nabble.com.