geospatial

问题 Problem: The add_grid function in the R mapdeck package is very exciting. However, following the CRAN documentation, I cannot seem to get any data to actually plot on the returned map. In other words, the map returns, but no data is plotted. Is this a known bug? Code: library(tidyverse) library(mapdeck) # - Enter mapdeck key ... Note that it is user-specific key <- rstudioapi::askForPassword() # - Read Example Data Set df <- read.csv(paste0( 'https://raw.githubusercontent.com/uber-common/deck

问题 I have a collections names locations with data structures like: { "_id" : ObjectId("4e95263f1783ae8487be26d4"), "name" : "test 1", "location" : { "coordinate" : { "latitude" : 40.731987, "longitude" : -73.999701 }, "address": "xxxxxxx" } } and want to make geo queries against location.coordinate field. When I'm trying to add index I get following results: $> db.locations.ensureIndex( { "location.coordinate" : "2d" } ) $> **** SyntaxError: syntax error (shell):0 Is it possible to use

问题 I am just wondering what kind of computing/programming language/frameworks are needed to produce images such as the one in http://www.erdas.com/ ? Programmatically, how does one produce the general spatial analysis images ? ps: I use java most of the time. Thanks 回答1: First of all, uDIG, OpenJUMP (not sure about this) cannot process images in a way that ERDAS can. These softwares are great, but they do not have extensive raster funcionality. You need to take a look at GDAL, which covers a

问题 I have been using the MBRWithin function for quite a lot of times. Suddenly I notice on google map this POINT(101.11857 4.34475) is out of the geo fence which I specify but it still give a value of 1 in mysql any reason or tweaking need to be done? SELECT MBRWithin(GeomFromText('POINT(101.11857 4.34475)'),GeomFromText('POLYGON((101.12112522125244 4.3531723687957164,101.11846446990967 4.351417913665312,101.13138198852539 4.336397898951581,101.13477230072021 4.33211863778494,101.14065170288086

问题 The following link in the Mapbox Javascript API describes how to add an image overlay on a map, and it is very simple : https://www.mapbox.com/mapbox-gl-js/example/image-on-a-map/ This works! However, I am trying to add an image overlay on a custom map. I am wanting to do this without creating tiles or anything of the like. I can't find a way to overlay an image on a satellite map (that's my goal, just a weather radar GIF on a satellite map), but I can't seem to get this to work on any other

问题 Borehole data contains the "collar" information: that's X,Y, and Z (Z is ground elevation, and Z=0 is some datum like mean sea level), and also borehole length in Z direction. How can I create a 3D plot of the borehole traces (curves)? I'm looking for solutions in R but also interested in python (though haven't tagged it as such in case it just confuses). The result might be similar to this image from ArcScene: . Here, the borehole traces are coloured by another parameter from one or more

问题 I'm trying to make use of ProportionalSymbolMap map as defined in this JSS paper. In order to plot proportional symbols I first need an object of map class. The methods I normally use however return SpatialPolygonDataFrame. Is there any package or method that could be of help here? 回答1: Hack is the way to go about it. I just used this set of commands to take apart a SpatialPolygons* object and put it back together again as an object of class map . I hope you like it: # read in shapefile as

问题 I'm trying to encapsulate a near query with a maxDistance in a MongoMapper backed model. I must be doing something silly in my query syntax. Model class Site include MongoMapper::Document key :id, Integer key :name, String key :location, Array ensure_index [[:location, '2d']] def self.nearest(center_point, range) where(:location => {'$near' => center_point, '$maxDistance' => range}).all end end Trying to get everything within 200 miles of a point... Site.nearest([-122.0,44.0],200) > Mongo:

问题 library(maps) 1> map.where(database="world",29.392089,53.592505) [1] "USSR" does anyone know how I can get an updated world map database to drive this function in the maps package? I need country names only for now, not detailed sub-national administrative information such as is available in at gadm.org. 回答1: Try wrld_simpl in the maptools package. require(maptools) data(wrld_simpl) plot(wrld_simpl) ## or subset based on the name plot(wrld_simpl[wrld_simpl$NAME == "Russia", ]) ## explore

问题 I am quite new to R and have recently been trying to create an outline of the UK in ggplot2 with the following code: library(ggplot2) UK <- map_data("world2Hires", region = "UK") ggplot() + geom_polygon(data = UK, aes(x = long, y = lat, group = group)) + coord_map() Result of ggplot2 code: This creates the map above as it does not take into account the longitude scale of the map and stretches it across the x-axis. The UK has a longitude that spans from -x to +x which is causing the problem