a bug in CircleQuery

[hunterlee]

line 34 in GeoHashCircleQuery.java is wrong: double halfRadius = radius / 2.0;

the "halfRadius" is meaningLess. you should use the radius to create the BoundingBox, which will exactly overlap the circle.

[kungfoo]

I must look at the testcase that checks that a circular query around WGS84Point(10.00254, 76.30627) with 2.5km radius does only yield one hash...

Can you provide a testcase?

[hunterlee]

sorry for delaying the response...

here is my test case: WGS84Point center = new WGS84Point(39.86391280373075, 116.37356590048701); //set the radius is 589 meters GeoHashCircleQuery query = new GeoHashCircleQuery(center, 589);

    //the distance between center and test1 is about 430 meters
    WGS84Point test1 = new WGS84Point(39.8648866576058, 116.378465869303); 
    //the distance between center and test2 is about 510 meters
    WGS84Point test2 = new WGS84Point(39.8664787092599, 116.378552856158);

    //return 2 hashes
    List<GeoHash> list = query.getSearchHashes();
    for(GeoHash hash : list) {  
        boolean status = hash.contains(test1);
        System.out.println(status);
        status = hash.contains(test2);
        System.out.println(status);
    }

result is: false false false false

that means neither of the searched geohash contains these two test points. however, the two points are in the circle.

[kungfoo]

I added your test case and fixes the code. I also added a new method that lets you easily check wether a WGS84Point is inside the bounding box defined by any query.

See: https://github.com/kungfoo/geohash-java/blob/master/src/test/java/ch/hsr/geohash/GeoHashCircleQueryTest.java

Cheers.