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移除书签Formula expressions for all the built-in rankers
Formula expressions for all the built-in rankers
Most of the other rankers can actually be emulated with the expression based ranker. You just need to pass a proper expression. Such emulation is, of course, going to be slower than using the built-in, compiled ranker but still might be of interest if you want to fine-tune your ranking formula starting with one of the existing ones. Also, the formulas define the nitty gritty ranker details in a nicely readable fashion.
- SPH_RANK_PROXIMITY_BM25 = sum(lcs*user_weight)*1000+bm25
- SPH_RANK_BM25 = bm25
- SPH_RANK_NONE = 1
- SPH_RANK_WORDCOUNT = sum(hit_count*user_weight)
- SPH_RANK_PROXIMITY = sum(lcs*user_weight)
- SPH_RANK_MATCHANY = sum((word_count+(lcs-1)*max_lcs)*user_weight)
- SPH_RANK_FIELDMASK = field_mask
- SPH_RANK_SPH04 = sum((4*lcs+2*(min_hit_pos==1)+exact_hit)*user_weight)*1000+bm25
