Spatial

What is Google map's spatial reference system using when you enter a lat, long into the maps search bar? I've found hints that it might be WGS84 but after converting to that coordinate system, nothing shows up when i paste the coordinates into the google maps search box. I am converting from GDA MGA 56. Sample: Input MGA56 coords: 336301, 6253363 Expected WGS86 coords: -33.8473340793201, 151.230631835944 I get: 16834916.928327594 -4008321.1020318186 Spatial coord systems: EPSG:28356 for MGA56 EPSG:900913 for WGS86 (google maps) I am using geotools to do the transform: CoordinateReferenceSystem

Hello I have a network in R using the igraph library Vertices: 616 Edges: 6270 Directed: TRUE No graph attributes. Vertex attributes: name, Lat, Lon. Edge attributes: V3. How can I generate two shapefiles for the Vertices and the Edges using the Lat, Lon info in the vertex? You can do this using the sp and maptools packages. There are handy functions writePointsShape() and writeLinesShape() in maptools that will write to the ESRI shapefile format. Before doing this, it is necessary to extract the lat/lon information from the graph vertices and put it into a SpatialPoints object for the

I found some open source R-Tree implementations in C#, but none with documentation nor signs of being used by someone else than the developer. Jader Dias The NetTopologySuite is a JTS port to C# and it contains a STRtree class which is a read-only R-Tree I know of none, but I would point out that libraries like this tend to: Get written (normally with some bugs). Bugs get ironed out though use. All active bugs are fixed Optional 'Latent' bugs which could never happen due to previous semantics of the platform on which the library operates crop up if the platform changes in some way. Thus lack

Application Version: JBoss 7.0.0, Oracle 11g (ojdbc6.jar) and JDK 6 version I have a problem when I am trying to insert the value for CLOB Data type using CLOB.createTemporary function, getting the below exception. java.lang.ClassCastException: org.jboss.jca.adapters.jdbc.jdk6.WrappedConnectionJDK6 cannot be cast to oracle.jdbc.OracleConnection After searching in multiple forums, did not find any solution. https://forums.oracle.com/forums/thread.jspa?threadID=279238 Basic steps required to deploy a WAR file and configuring the JBoss oracle driver pool configuration is done. But, still not able

Hi have some question regarding spatial and temporal locality. I have read in the course theory that spatial locality If one item is referenced, the likelihood of other address close by will be referenced soon temporal locality One item that is referenced at one point in time it tend to be referenced soon again. Ok, but how do I see that in the code? I think I understood the concept for temporal locality but I don't understand spatial locality yet. For instance in this loop for(i = 0; i < 20; i++) for(j = 0; j < 10; j++) a[i] = a[i]*j; The inner loop will call same memory address when

I have a matrix data with spatial coordinates and one variable. The spatial resolution is 1000 meters. > str(dat1) > List of 3 > $ x: num [1:710] 302340 303340 304340 305340 306340 ... > $ y: num [1:1241] 5431470 5432470 5433470 5434470 5435470 ... > $ z: num [1:710, 1:1241] 225 225 225 225 225 ... I want to convert it into raster format. > dat1$x[1:10] > [1] 302339.6 303339.6 304339.6 305339.6 306339.6 307339.6 308339.6 309339.6 310339.6 311339.6 > dat1$y[1:10] > [1] 5431470 5432470 5433470 5434470 5435470 5436470 5437470 5438470 5439470 5440470 I used the following code to do it. But the

I have a set of begin and end coordinates that look like this: begin.coord <- data.frame(lon=c(-85.76,-85.46,-85.89), lat=c(38.34,38.76,38.31)) end.coord <- data.frame(lon=c(-85.72,-85.42,-85.85), lat=c(38.38,38.76,38.32)) I am trying to create a set of 3 line segments by connecting each begin point to its corresponding end point. I would like the end product to be a SpatialLines object so that I can use the it with over function in the sp package. Here's a way: ## raw list to store Lines objects l <- vector("list", nrow(begin.coord)) library(sp) for (i in seq_along(l)) { l[[i]] <- Lines(list

PostgreSQL supports a variety of geometric types out of the box, along with lots of geometric operators and GiST indexes which seem to offer spatial indexing of data. And then there's also PostGIS , which is an extension to PG. What is the difference between the built-in spatial support in PG and PostGIS? If my application needs to store geographical coordinates (points, areas, polygons) and then efficiently do queries (such as point-in-polygon, polygon intersection), do I need PostGIS or can I use the (arguably) more convenient and simpler built-in data types / syntax? First I'd like to

My goal is to use mysql POINT(lat,long) to find nearby entities in the database. I'm trying to do something like in the bottom of this tutorial http://www.scribd.com/doc/2569355/Geo-Distance-Search-with-MySQL . Here is what I have got: Table: CREATE TABLE mark ( id INT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY, name VARCHAR(20) DEFAULT NULL, loc POINT NOT NULL, SPATIAL KEY loc (loc) ) ENGINE=MyISAM; Inserting some test-data: INSERT INTO mark (loc,name) VALUES (POINT(59.388433,10.415039), 'Somewhere 1'); INSERT INTO mark (loc,name) VALUES (POINT(63.41972,10.39856), 'Somewhere 2'); Declaring