geospatial

问题 I have a table 'floating_options', and I want to create a spatial index on a column 'area_geo' (which is a sdo_geometry column, with two rows of data that appear as expected when I select * from floating_options). I have used the following code but I am receiving the error below. I would be very grateful for any help! Thanks! CREATE INDEX area_idx ON floating_options(area_geo) INDEXTYPE IS MDSYS.SPATIAL_INDEX; Error report - SQL Error: ORA-29855: error occurred in the execution of

问题 I have a table 'floating_options', and I want to create a spatial index on a column 'area_geo' (which is a sdo_geometry column, with two rows of data that appear as expected when I select * from floating_options). I have used the following code but I am receiving the error below. I would be very grateful for any help! Thanks! CREATE INDEX area_idx ON floating_options(area_geo) INDEXTYPE IS MDSYS.SPATIAL_INDEX; Error report - SQL Error: ORA-29855: error occurred in the execution of

问题 Problem statement: With ggquiver::geom_quiver() we can plot vector fields, provided we know x , y , xend , and yend . How can I calculate these parameters for an arbitrary RasterLayer of elevations? How can I ensure that the size of these arrows indicates the slope for that particular vector such that the arrows appear different lengths proportional to the gradient at that location (e.g., the first plot below)? Background: # ggquiver example library(tidyverse) library(ggquiver) expand.grid(x

问题 Problem statement: With ggquiver::geom_quiver() we can plot vector fields, provided we know x , y , xend , and yend . How can I calculate these parameters for an arbitrary RasterLayer of elevations? How can I ensure that the size of these arrows indicates the slope for that particular vector such that the arrows appear different lengths proportional to the gradient at that location (e.g., the first plot below)? Background: # ggquiver example library(tidyverse) library(ggquiver) expand.grid(x

问题 Problem statement: With ggquiver::geom_quiver() we can plot vector fields, provided we know x , y , xend , and yend . How can I calculate these parameters for an arbitrary RasterLayer of elevations? How can I ensure that the size of these arrows indicates the slope for that particular vector such that the arrows appear different lengths proportional to the gradient at that location (e.g., the first plot below)? Background: # ggquiver example library(tidyverse) library(ggquiver) expand.grid(x

问题 This all new to me, so bear with me... I'm working on a Visual Studio project; it's a web service that returns some data. I've just tried to make a particular call to the web server on my local machine (IIS) and I'm getting this error: Unable to load DLL 'SqlServerSpatial140.dll': The specified module could not be found Before anyone says it - yes, obviously I am missing this DLL file. I've searched online and don't see where I could download it from (I have Microsoft SQL Server System CLR

问题 This all new to me, so bear with me... I'm working on a Visual Studio project; it's a web service that returns some data. I've just tried to make a particular call to the web server on my local machine (IIS) and I'm getting this error: Unable to load DLL 'SqlServerSpatial140.dll': The specified module could not be found Before anyone says it - yes, obviously I am missing this DLL file. I've searched online and don't see where I could download it from (I have Microsoft SQL Server System CLR

问题 I am attempting to utilize the spatial index. I have a table of ips, and a ip2geo table with ip block ranges. I'm attempting to assign Geo ID to each ip from the ip2geo table When attempting to to selected using a columns value the Spatial Index doesn't doesn't get used. EXPLAIN SELECT *, ( SELECT locid FROM `ipblocks` i WHERE MBRCONTAINS(i.ippolygon, POINTFROMWKB(POINT(h.`ip`, 0))) ) AS locaid FROM `ips` h LIMIT 1; id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY

来源： https://stackoverflow.com/questions/41371170/ggsn-global-map-scale-bar-looks-wrong

来源： https://stackoverflow.com/questions/64569984/how-to-generate-10x10km-grid-cells-of-all-countries