I'm not sure I understood your request properly... If you want to create a dimension that ranks the products, you can do it using the Advanced Aggregation function AGGR, like this:
AGGR( rank(sum([NBR_VOTE])), Product)
I'm not sure what you mean when you say "in the same dimension". I suppose you could create a "Dual" value, with the Product name as a text and its rank as a number:
Notice the second parameter "4" in the Rank() function - you need to add it, in order to ensure that each product receives a unique rank number.
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