I just got my hands on elasticsearch yesterday, because we had a requirement of evaluating complex mathematical queries for comparison like "evaluating eculadian distances" rather than simple text matching.
I read that in elasticsearch, we can execute scripts as well as native (java) scripts for evaluating custom scores.
So my first question was 1. what is the score exactly? and how is it evaluated?
2. when i am using SearchRequestBuilder (in JAVA API) and sorting, and then taking out score it gives NaN wheres it gives type/index.
3. and also could anyone point me in right direction of "how to evaluate custom scores depending on the values in the file". Ok exactly what i am doing is i am hashing images into feature vectors which are stored in a file. Now to compare two feature vectors i have to calculate a distance between them, so this distance which gives similarity factor should decide the score (from what i get score is). so how to do it? i heard that we could use native scripts for that, but couldn't get it exactly.
Thanking everyone in advance.