Syntax for hsin query in solr

I have created a database and have used dataimport for retrieving the data. I tried out the hsin query:

http://localhost:89开发者_JAVA技巧83/solr/select/?q=name:Denver AND _val_:"recip(hsin(0.611941,-1.567437,lat_rad,lng_rad,3963.205),1,1,0)"^100

Though there are records that are retrieved, when the value of the radius is drastically reduced (7.205), the ranking for links change. Why is there a change in ranking? The number of records retrieved should have reduced. But this has not happened.

Solr 3.1 has been released, and for basic geosearch it's much easier to use the higher level spatial support outlined here: http://wiki.apache.org/solr/SpatialSearch rather than low level functions like hsin().

Anyway, to more specifically answer your question, a function query matches all documents by default. Also, the "radius" in the hsin function refers to the radius of the sphere (e.g. the radius of the earth) and not the radius you are searching within.