Spatial

I have a database table which currently holds geometric data in SRID 27700 (British National Grid). While retrieving the data however I need to transform it to SRID 4326 (WGS84). Is there any way to apply a function such as ST_Transform found in PostGIS to my data in order to get the result I need? NOTE: The solution needs to be able to be implemented using T-SQL and not stored procedures etc. I have to be able to construct a statement and have it saved in a table as a string field for retrieval later. This is because my solution is database agnostic. The way I am currently doing this in

I am working on Web Api with OData enabled. I started working by referring to ( only the relevant dlls to the question are mentioned ) Microsoft.AspNet.WebApi.OData Microsoft.Data.OData Microsoft.Data.Edm System.Spatial But when I found out OData is by default case-sensitive , I look for a solution of case insensitive and I have gone through few post Support OData Uri case insensitive parse & ODataLib 6.7.0 Release then finally landed into nuget package Microsoft.OData.Core 6.9.0 which seems to be solving my problem. Here my confusion starts , It has its own collection related libraries under

记录一些关于mysql的实践信息 索引类型分为：FULLTEXT、NORMAL、SPATIAL、UNIQUE 索引方法：BTREE、HASH FULLTEXT：全文索引，只针对英文有效，提升使用like %xxx%检索效率 NORMAL：一般索引， SPATIAL：空间索引，使用RTREE的方式，存储几何二进制大数据搜索。 组合索引：就是多个字段组成一个索引叫组合索引，需要注意组合索引有最左优先算法，比如（A,B,C）查询条件中(A)、(A,B)、(A,B,C)会使用索引，（B)、（C）、（B,C）的查询都不会使用索引。同时使用组合索引时，需要注意select后面的字段会影响是否走索引，需要多用EXPLAIN来检查查询情况，尤其是带有OR的查询语句。 组合索引中限制条件比较多，得多检查下索引使用情况。 来源： https://my.oschina.net/uwith/blog/3105365

I have an application that receives a number of datums that characterize 3 dimensional spatial and temporal processes. It then filters these datums and creates actions which are then sent to processes that perform the actions. Rinse and repeat. At present, I have a collection of custom filters that perform a lot of complicated spatial/temporal calculations. Many times as I discuss my system to individuals in my company, they ask if I'm using a rules engine. I have yet to find a rules engine that is able to reason well temporally and spatially. (Things like: When are two 3D entities ever close?

I have a table which has a POINT column containing the latitude and longitude of various locations. I then also have a users location from geo-location in the browser. What I need to be able to do is find all records from the table where the POINT value in the is within a 10 km radius (or X km radius), ordered by distance with the closest first. My table has a SPATIAL index on the POINT column. I'm currently working on a project where I'm calculating distances between multiple locations. I'm using the following query for selecting object_id's which are within a given radius. SELECT id, ( 6371

I've produced this map in ggplot2 : library(maptools); library(ggplot2) data(wrld_simpl) world <- fortify(wrld_simpl) worldUk <- subset(world, id=="GBR") ggplot() + geom_path(aes(long, lat, group=group), data=worldUk, color="black", fill=NA) + coord_equal() Using photoshop, I've added a scale bar to the map. How can I add a similar scale bar using ggplot2 ? This post adds a scale bar, but the bar doesn't refer to distance: scale bar and north arrow on map-ggplot2 There is a library called ggsn , which allows you to customize the scale bar and north arrow. ggplot() + geom_path(aes(long, lat,

I have a RasterBrick consisting of monthly rainfall data over 7 years, so it has 7 layers with 12 slots each: rainfall <- brick("Rainfall.tif") > rainfall class : RasterBrick dimensions : 575, 497, 285775, 7 (nrow, ncol, ncell, nlayers) resolution : 463.3127, 463.3127 (x, y) extent : 3763026, 3993292, -402618.8, -136213.9 (xmin, xmax, ymin, ymax) coord. ref. : +proj=sinu +lon_0=0 +x_0=0 +y_0=0 +a=6371007.181 +b=6371007.181 +units=m +no_defs data source : in memory names : layer.1.1, layer.2.1, layer.1.2, layer.2.2, layer.1, layer.2, layer min values : 239.6526, 499.8343, 521.0316, 617.2896,