Spatial

问题 I’m using Solr 4.3.0 with an up to date version of JTS and spatial4j. As field type in my schema.xml i’m using “location_rpt” like the description in the documentation. Documentation <field name="standort" type="location_rpt" indexed="true" stored="true" /> Now when my Application create a FilterQuery like this standort:"IsWithin (POLYGON((16.243972778320312 48.27016879304729, 16.411170959472656 48.268340583150504, 16.44275665283203 48.19058119922813, 16.32396697998047 48.15921534239267,16

问题 I have raster of the following features: library(raster) library(rgeos) test <- raster(nrow=225, ncols=478, xmn=-15.8, xmx=32, ymn=-9.4, ymx=13.1) I want to mask in this raster the cells that are within a given distance of a point. I create the spatial points as followed: p2=readWKT("POINT(31.55 -1.05)") Then I create a spatial polygon object by adding a 0.5 buffer: p2_Buffered <- gBuffer(p2, width = 0.5) mask(test, mask=p2_Buffered,inverse=T) When I mask my raster given this spatial object,

问题 I have two datasets (csv format) of different lengths, both containing addresses as well as coordinates (log and lat). The both have this shape (example Dataset A): ID Address lat long 1 Lausitzer Strasse, 20/22, 2991, Lauta, Germany 51.46228 14.09522 2 Parkstrasse, 6, 2991, Lauta, Germany 51.4631141 14.1109184 3 Parkstrasse, 6, 2991, Lauta , Germany 51.4631141 14.1109184 4 Arndtstrasse, 27, 2991, Lauta, Germany 51.44664 14.10287 5 Goethestrasse, 13, 4746, Hartha, Germany 51.0965679 12

问题 I am currently exploring three shapefiles, each with point data, and all confined to the same window. I also have them in ppp format which I've used to create kernel density maps. plot(density.ppp(smktppp, 0.5, edge=T), main="Supermarket Density") plot(density.ppp(tptppp, 0.5, edge=T), main="Transport Density") plot(density.ppp(farmppp, 0.5, edge=T), main="Urban Farm Density") I would like to overlay these plots, using map algebra, or fuzzy logic, etc, to create one output map showing the

问题 In the example page it is shown how to do a neighbor search with a limit on the number of returned items. Is it possible to also specify a distance limit? I.e.: Return all items that are at most X distance from the point, and further limit the result to Y number of items." 回答1: No, if you need distance, use OVERLAPS. https://tarantool.org/doc/book/box/box_index.html#rtree-iterator 来源： https://stackoverflow.com/questions/39644902/spatial-search-for-neighbor-with-distance-limit

问题 We have a large location DB - with lat long specified for each row. The DB is hosted in MySQL. We need to run two type of queries: places nearby (sort by distance) places nearby by category (where category is a column) With the number of records growing, this query seems to slow down drastically. SELECT *, ( 3959 * acos( cos( radians(40.759105) ) * cos( radians( Latitude ) ) * cos( radians( longitude) - radians(-73.984654) ) + sin( radians(40.759105) ) * sin( radians( Latitude ) ) ) ) as

问题 I try to map a SqlServer2008 geometry with FluentNHibernate. I am using NHibernate version 4.0.0.4000. I installed NHibernate.Spatial, NetTopologySuite, GeoAPI and NHibernate with FluentNhibernate all with NUget. My Fluent mapping looks like this: public class ArealMap: ClassMap<Areal> { public Areal() { Table("Areal"); Id(x => x.Id).Column("Id").GeneratedBy.Identity(); Map(x => x.Geometry).Column("Geometry").CustomType(typeof(MsSql2008GeometryType)); } } public class Areal { .... public

问题 I have the following query: var nodes = DB.Nodes .Where(x => x.Lon > 486400 && x.Lon < 486600 && x.Lat > 5025100 && x.Lat < 5025300) .Join(DB.RoadNodes, x => x.Id, y => y.NodeId, (x, y) => x); This searches all the nodes in DB.Nodes near a certain location, then it checks whether the node is a road junction by taking a join with DB.RoadNodes ; however, this takes several seconds which is slow. It looks like I have to do two things here: Optimize the Where part which takes ~5 seconds on its

问题 I want to combine the SpatialPolygonsDataFrame of two neighbour countries like Pakistan and India. My MWE is below: library(raster) Pakistan.adm1.spdf <- getData( "GADM" , country = "Pakistan" , level = 1 ) India.adm1.spdf <- getData( "GADM" , country = "India" , level = 1 ) How can I combine these two shapefiles? 回答1: From the answer to this question, use rbind and the argument makeUniqueIDs . adm1.spdf <- rbind(Pakistan.adm1.spdf, India.adm1.spdf, makeUniqueIDs = TRUE) plot(adm1.spdf) 来源：

问题 I´m looking for a way to create a SpatialPolygonsDataFrame from a list of SpatialPolygons? In the following there´s an example of a list of Polygons from which a SpatialPolygonsDataFrame, containing all Polygons of the list, should be created. EDIT: The SpatialPolygonsDataFrame must be created from the list of SpatialPolygons! As my original data doesn´t contains SpatialPolygons as separate values but the list of SpatialPolygons. The way I received this list is different form the one in the