I am using mongodb with polygons stored with geometry in this format
"geometry" : { "type" : "Polygon", "coordinates" : [ [ [ 2.0315, 85.8546219515 ], [ 2.0315, 86.1673780485 ], [ 1.7185, 86.1673780485 ], [ 1.7185, 85.8546219515 ], [ 2.0315, 85.8546219515 ] ] ] }
I am trying to use geoIntersect and query a rectangle polygon using something like this:
find({geometry:{$geoIntersects:{$geometry:{"type": "Polygon", "coordinates":[ [[12,20], [13,20], [13,18], [12,18], [12,20]]]}}}})
When I do small queries like that, the results are fine, but when I expand to really large boxes:
find({geometry:{$geoIntersects:{$geometry:{"type": "Polygon", "coordinates":[ [[-166.2890625,46.55886030311719], [-166.2890625,47.39834920035926], [12.12890625,47.39834920035926], [12.12890625,46.55886030311719], [-166.2890625,46.55886030311719]]]}}}})
then I start getting really odd results like
"geometry" : { "type" : "Polygon", "coordinates" : [ [ [ 2.9684999999999997, 85.54162195149999 ], [ 2.9684999999999997, 85.8543780485 ], [ 2.6555, 85.8543780485 ], [ 2.6555, 85.54162195149999 ], [ 2.9684999999999997, 85.54162195149999 ] ] ] }
I am only returned a few polygons (4 total) from the db that are actually inside my input polygon:
"geometry":{"type":"Polygon","coordinates":[[[12.343499999999999,47.1416219515],[12.343499999999999,47.454378048500004],[12.0305,47.454378048500004],[12.0305,47.1416219515],[12.343499999999999,47.1416219515]]]}}
"geometry":{"type":"Polygon","coordinates":[[[12.343499999999999,46.829621951499995],[12.343499999999999,47.1423780485],[12.0305,47.1423780485],[12.0305,46.829621951499995],[12.343499999999999,46.829621951499995]]]}}
"geometry":{"type":"Polygon","coordinates":[[[-166.0935,46.5166219515],[-166.0935,46.829378048500004],[-166.4065,46.829378048500004],[-166.4065,46.5166219515],[-166.0935,46.5166219515]]]}}
"geometry":{"type":"Polygon","coordinates":[[[-166.0935,46.829621951499995],[-166.0935,47.1423780485],[-166.4065,47.1423780485],[-166.4065,46.829621951499995],[-166.0935,46.829621951499995]]]}}
I shouldn't have any latitudes in the 80's with my input. I don't know where these are coming from. They make up the majority of what is returned. (847/851 results)
I don't think the polygon fits in one hemisphere. From the $geoIntersects docs,
Any geometry specified with GeoJSON to $geoIntersects queries, must fit within a single hemisphere.
Related
I am trying to run a mongoldb query on a GEOjson collection of points and polygons but I'm struggling. I am new to GEOjson and Mongodb and haven't been able to find any examples on how to do this via google search and S.O. search so I'm hoping someone can shed some light on my issue.
I have created a 2DSphere index on geometry.coordinates - not sure if that's correct or not.
My overall objective is to return all points within the current map view and add both the point and the polygon associated to the map. I am using Leaflet.js and understand how to add to the map, but I can't figure out the query on Mongodb to get the results.
Just looking to find out if my GEOjson is correct and maybe an example on how I would perform the search on my GeometryCollection and get the point using $geowithin and then get the associated polygon.
Here's an example of my GEOjson-
{
"_id" : ObjectId("5709722f4044ccc4b8291651"),
"type" : "Feature",
"geometry" : {
"type" : "GeometryCollection",
"geometries" : [
{
"type" : "Point",
"coordinates" : [
-105.960805584616,
39.4671896545181
]
},
{
"type" : "Polygon",
"coordinates" : [
[
[
-105.96110187372227,
39.463449804295806
],
[
-105.96602244670311,
39.462956063632134
],
[
-105.96577627486317,
39.46671592928652
],
[
-105.96553007974012,
39.470475771657675
],
[
-105.96047434857059,
39.47089761421853
],
[
-105.95541854755197,
39.471319247231634
],
[
-105.95579990086372,
39.46763141937862
],
[
-105.95618125417559,
39.463943568242485
],
[
-105.96110187372227,
39.463449804295806
]
]
]
}
]
},
"properties" : {
"processed" : "Yes"
}
}
I have the following document in the entities collection at Mongo (a 2dsphere index for location.coords is in place):
> db.entities.find({},{location: 1}).pretty()
{
"_id" : {
"id" : "en3",
"type" : "t",
"servicePath" : "/"
},
"location" : {
"attrName" : "position",
"coords" : {
"type" : "MultiPoint",
"coordinates" : [
[
-3.691944,
40.418889
],
[
4.691944,
45.418889
]
]
}
}
}
As far as I have checked, $geoWithin only matches when the geometry includes all the points of the MultiPoint, e.g:
> db.entities.find({"location.coords": { $geoWithin: { $centerSphere: [ [ -3.691944, 40.418889 ], 0.002118976612776644 ] } } })
// Small circle centered at first point, but without covering the second point: it doesn't matchh
> db.entities.find({"location.coords": { $geoWithin: { $centerSphere: [ [ -3.691944, 40.418889 ], 2 ] } } })
// Big circle centered at first point covering also the second point: it matches
However, I would like to have a query to match if at least one point of the MultiPoint matches. I have read about the $geoIntersects operator. I have tried just replace $geoWithin by $geoIntersect in my query, but it doesn't work:
> db.entities.find({"location.coords": { $geoIntersects: { $centerSphere: [ [ -3.691944, 40.418889 ], 0.002118976612776644 ] } } })
error: {
"$err" : "Can't canonicalize query: BadValue bad geo query",
"code" : 17287
}
Reading the $geoIntersects operator, it seems that it can be only used with polygons or multi-polygons, but it doesn't mention circles. I wonder if I'm missing something, because this "asymmetry" between $geoWithin and $geoIntersects seems to be a bit weird...
Thus, is there any way of doing a geo-query using a circle as area to match at least one of the points of MultiPoint object?
I think I have found the answer at the end. It can be done with the $near operator, in the following way:
db.entities.find({"location.coords": { $near: { $geometry: { type: "Point", "coordinates": [ -3.691944, 40.418889 ] }, $maxDistance: 0.5 } }})
I'm using $geoWithin on a large list of geographic regions, defined in geoJSON. Some of these regions are Polygons, and some are MultiPolygons.
MultiPolygons fail, with a non-descript Malformed geo query error. After experimenting with the repl, I found I can't get mongo to take any MultiPolygon.
This is a minimal example:
{
"type" : "MultiPolygon",
"coordinates" : [
[
[
[ 9.560016, 42.152492 ],
[ 8.746009, 42.628122 ],
[ 9.390001, 43.009985 ],
[ 9.560016, 42.152492 ]
]
]
]
}
GEOJSONLint says it's fine, and shows me a triangle in the map, but mongo won't take it.
How is it malformed?
I have a collection in MongoDB with a 2dsphere index. The object I want to save looks like this:
{
"type" : "Polygon",
"coordinates" : [
[
[
5.052617929724351,
52.64653192570052
],
[
5.051738165167465,
52.64765805672784
],
[
5.054162882116928,
52.64831549553909
],
[
5.054592035559312,
52.64780777138566
],
[
5.055364511755601,
52.64790541110375
],
[
5.056094072607651,
52.64688343792051
],
[
5.054237983969346,
52.64661654927096
],
[
5.052617929724351,
52.64653192570052
]
]
]
}
According to http://geojsonlint.com/ this is perfectly valid GeoJSON. However MongoDB says it can't extract the geo keys because the GeoJSON might be malformed.
Can anyone help me out and spot the mistake?
This is the MongoDB error I get:
insertDocument :: caused by :: 16755 Can't extract geo keys from object, malformed geometry?
The problem is that you are not providing the name of the top level object that the GeoJSON would be assigned to.
You must have created the "2dsphere" index on the "coordinates" field. Instead you want to create it on the field that this entire GeoJSON value will be assigned to.
db.geo.createIndex({"location":"2dsphere"})
db.geo.insert({"location" : {
"type" : "Polygon",
"coordinates" : [
[ <list of your-coord-pairs> ]
]
}})
WriteResult({ "nInserted" : 1 })
using mongo, I would like to compare a user's geo coordinates to a collection of documents each representing a defined geographical boundary. This is what i have thought to do, but cant get working. Other suggestions to get the same result are also welcome.
A document from the collection looks like this (those are manhattan coordinates, if you draw a line in sequence from one coordinate to the next, it wraps manhattan)
{
"__v" : 1,
"_id" : ObjectId("53220803a74a16da9c729202"),
"name" : "Manhattan",
"boundary" : {
"type" : "Polygon",
"coordinates" : [
[
[
-74.01237999999999,
40.69967
],
[
-73.97895,
40.71076
],
[
-73.97169,
40.73049
],
[
-73.92828,
40.79605
],
[
-73.95547999999999,
40.82635
],
[
-74.00901,
40.75431
],
[
-74.01961,
40.7059
]
]
]
}
}
i then use the following query to make my check
db.collection.find( { boundary :
{ $geoIntersects :
{ $geometry :
{ type : "Point" ,
coordinates : [ [user_long, user_lat] ]
} } } } ).exec(function(err, city){
console.log(err, "error");
res.send({agent_count : city});
});