Elasticsearch displaying incorrect distance

Question

I have the following elasticsearch query:

{
"from": 0,
"size": 10,
"fields": ["returnresults"],
"script_fields": {
    "distance": {
        "params": {
            "lat": -41.166670,
            "lon": 146.350000
        },
        "script": "doc[\u0027location\u0027].distanceInKm(lat,lon)"
    }
},
"track_scores": true,
"sort": [{
    "_geo_distance": {
        "searchindex.location": [146.350000,
        -41.166670],
        "order": "asc",
        "unit": "km"
    },
    "_score": {
        "order": "desc"
    }
}],
"query": {
    "query_string": {
        "query": "7383492",
        "fields": ["total"]
    }
},
"filter": {
    "and": [{
        "query": {
            "range": {
                "expiry": {
                    "gt": 1393285386
                }
            }
        }
    },
]
}
}

When I run the query, it is finding some matching results, however the distance it is reporting is wrong.

For a geocode overseas at coord: 37.445796966553,-122.16209411621

It returns the result as been 31145km away. Which is not possible.

Am I doing something wrong in my query, or is this an issue inside elasticsearch itself. I don't seem to have an issue with short distances, but that could be the % it is off is only minor because of it being a short distance.

I am currently using Elasticsearch 0.90.2

Any help would be appreciated.

score 1 · Accepted Answer · edited May 23 '17 at 12:03

I was curious about whether the issue answered in : Wrong distance returned by ElasticSearch distanceInKm accounted for this issue.

My quick and dirty test of the two algorithms came up with plane distance = 19352 mi (31144 km) and arc distance = 7915.7 mi (12739 km), so it does seem to account for the stated discrepancy pretty nicely. I found it interesting anyway, so if it's of interest to anyone else:

public static void main(String []args){
    double targetLongitude = 146.350000;
    double sourceLongitude = -122.16209411621;
    double targetLatitude = -41.166670;
    double sourceLatitude = 37.445796966553;
    double DISTANCE_PER_DEGREE = 69.16944444;
    double EARTH_RADIUS = 3958.76;

    //Plane distance
    double px = targetLongitude - sourceLongitude;
    double py = targetLatitude - sourceLatitude;
    double distanceMiles = Math.sqrt(px * px + py * py) * DISTANCE_PER_DEGREE;

    System.out.println(distanceMiles);


    //Arc distance
    double longitudeDifference = targetLongitude - sourceLongitude;
    double a = Math.toRadians(90D - sourceLatitude);
    double c = Math.toRadians(90D - targetLatitude);
    double factor = (Math.cos(a) * Math.cos(c)) + (Math.sin(a) * Math.sin(c) * Math.cos(Math.toRadians(longitudeDifference)));

    if (factor < -1D) {
        System.out.println( Math.PI * EARTH_RADIUS);
    } else if (factor >= 1D) {
        System.out.println(  0);
    } else {
        System.out.println(  Math.acos(factor) * EARTH_RADIUS);
    }
}

Elasticsearch displaying incorrect distance

1 Answers1