valhalla / valhalla

Open Source Routing Engine for OpenStreetMap
https://valhalla.github.io/valhalla/
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Normalize Edge Scores #1154

Open dnesbitt61 opened 6 years ago

dnesbitt61 commented 6 years ago

Edge scores should be computed in such a fashion that extremely large edge scores are thrown out. The current logic quickly generates scores that often exceed 24 hours, which is far too great a penalty and leads to very poor performance in some cases (penalty of 24 hours led to bicycle routes taking 10-20 seconds). Some maximum value should be determined and scores should be normalized to lie between 0 and that value.

dnesbitt61 commented 6 years ago

Perhaps loki could store a distance value and then thor could transform it into a score using sif in a way that normalizes the costs over a range. Once we get to fuzzy matching then we'll need some way of using that as well, maybe not combine with the score have one as match score and one as distance and then let whatever algorithm choose what to do with those numbers. (basically keep them separate)