geospatial

问题 Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers. Want to improve this question? Update the question so it's on-topic for Stack Overflow. Closed 3 years ago . Improve this question I'm looking for a Java library that is capable of performing spatial calculations on sets of lat/lon data. Here are some of the functions that I'm looking for: Calculate the Great Circle distance between two points Determine if a point lies within a simple closed

问题 I am trying to create square buffers around given points, I am able to create circular buffers but not square ones. from shapely.ops import transform from shapely.geometry import Point local_azimuthal_projection = "+proj=aeqd +R=6371000 +units=m +lat_0={} +lon_0={}".format(lat, lon) wgs84_to_aeqd = partial( pyproj.transform, pyproj.Proj('+proj=longlat +datum=WGS84 +no_defs'), pyproj.Proj(local_azimuthal_projection), ) aeqd_to_wgs84 = partial( pyproj.transform, pyproj.Proj(local_azimuthal

问题 I'm trying to fill a combined categorical and continuous variable on a map. So, for instance, in my minimally reproducible example below, say I want to display the number of KrispyKreme Donut shops in each county, which is generally a continuous variable I want to fill on a gradient. But I also have counties that forbid KrispyKremes indicated by a "-1" and those that have them under construction "-2". I want to display these in a different color not mapped on the gradient. I also have NA in

问题 I have a spatial and temporal df: 'date' 'spatial_pixel' 'column_A' ... ---- ----- --- 2012-04-01 | 1000 | 5 2012-04-01 | 1001 | 1 ... ... ... I want a column (groupedby 'spatial_pixel' and 'date') that counts the days-in-a-row a boolean is met. Say 'column_A' < 2: 'date' 'spatial_pixel' 'column_A' 'days-in-a-row' ... ---- ----- --- ---- 2012-03-30 | 1001 | 5 | 0 2012-04-01 | 1001 | 1 | 1 2012-04-02 | 1001 | 1 | 2 2012-04-03 | 1001 | 3 | 0 ... ... ... ... My Attempts: First, I made a new

问题 I am trying to create a route to retrieve the records with nearby location coordinates. I checked the logs and found the "docs" value as undefined. What am I going wrong with? router.get('/userlist/:lat/:lng', function (req, res) { var db = req.db; var lat = req.params.lat, lng = req.params.lng; console.log("lat "+lat); console.log("lng "+lng); var collection = db.get('userlist'); collection.find({ "location": { $nearSphere: { $geometry: { type: "Point" , coordinates: [ lat , lng ] } } } }, {

问题 I have a shape file of a road network and another shape-file containing area boundaries. Is there any better code that I can use to get length of roads that lies inside each polygon? This Question was asked earlier with the difference that I want to use R instead of QGIS. I tried: intersec=intersect(roads,Polygon) road_length=tapply(intersec$length, intersec$polygon, sum) This works, but the problem is that the intersection does not divide the length of the roads, that cross to Polygons, but

问题 I'm playing with geo features of mongodb in Java and i'm facing to the following problem running command 'geoNear': Given: A collection named 'GEOENTITIES' with GeoJSON objects This collection is indexed with the Java code (using Jongo): collection.ensureIndex("{ coordinates : '2dsphere' }"); A document (named 'A' for the example) exists with coordinates equals to [48.0, 9.0] When executing : {geoNear: 'GEOENTITIES', near: [48.0,9.1], spherical: true, num: 5, distanceMultiplier: 6371} Then: I

问题 I'm trying to produce a choropleth map of county level data on COVID-19 infections using R. I'm a relative newbie to R so.... I've done some fairly basic stuff with ggmap to plot spatial data, but never anything quite like this. Typically I just have points of interest that I need to overlay on a map, so I can use geom_point and their lat/lon. In this case I need to construct the underlying map and then fill regions and I'm struggling with doing that in the ggplot world. I've followed some

问题 I am very excited the spatial abilities of Leaflet combined with R but I badly need the possibility to move around markers and/or draw paths over maps. As far as I see the Leaflet R package lacks this option albeit the original Java version could be forced this way. Do you have any idea? 回答1: The question is quite high-level, but that being said, there is an answer here that provides a solution for drawing points on a map in a shiny app. If you want to add lines between points and show the

问题 I'm using Gaussian Process model for prediction, and I'm now at the point where I need to use Grid file based on the coordinates I have in my data but I don't have one and I don't know how to create it. I followed the post on this link , but it shows the grid on Pennsylvania not Chicago where my data coordinates located! So I'm confused which will be the ideal way to create grid file including the other columns in the data. station <- data.frame(lat = c(41.997946, 41.960669, 41.960669, 41