Hi Ankit, Vincenty is the most accurate one — it is the benchmark for the other 2’s tests for the true answer. In theory it produces the same answers as the other 2 simpler formulas you mention but is “numerically robust” for computers. Note that the world model used by Spatial4j when in “geo” mode is a spherical model. For more accurate distance computation on Earth, use an ellipsoidal model. If you google “Vincenty”, it's easy to find Vincenty’s ellipsoidal formula with the constants for Earth; that is most often what he is associated with.
~ David Smiley Freelance Apache Lucene/Solr Search Consultant/Developer http://www.linkedin.com/in/davidwsmiley On Mon, Dec 22, 2014 at 12:35 AM, <ankit.mura...@ril.com> wrote: > > Dear All, > > We are using lucene spatial strategy to find out the distance between a > pair of Lat/Long. > > Given a pair of Lat/Long I need to find the near accurate distance between > these 2 points. > > I have used Haversine, LawOfCosines and Vincernity however unable to > decide which will provide the best output(accurate output). > > There is not just 1 point but millions of points which will need to be > passed into against a set of point to find the closest point. > > Which might be the best approach. Additionally, I observed from the API, > that the output of these 3 algorithms are in Degress. Is there any API in > lucene which can return the output in double,long,int etc. formats. > > > "Confidentiality Warning: This message and any attachments are intended > only for the use of the intended recipient(s). > are confidential and may be privileged. If you are not the intended > recipient. you are hereby notified that any > review. re-transmission. conversion to hard copy. copying. circulation or > other use of this message and any attachments is > strictly prohibited. If you are not the intended recipient. please notify > the sender immediately by return email. > and delete this message and any attachments from your system. > > Virus Warning: Although the company has taken reasonable precautions to > ensure no viruses are present in this email. > The company cannot accept responsibility for any loss or damage arising > from the use of this email or attachment." >
