geospatial

Converting from longitude\latitude to Cartesian coordinates

I have a earth coordinates given as longitude and latitude (WSG-84). How you i convert them to Cartesian coordinates (x,y,z) with the origin at the center of the earth? ...

With SQL2008 Spatial functions, How can I generate a polygon containing the results of an aggreation

I've got a table of points, each with a name, latitude, longitude, and an area code. What I'd like to do is perform an aggregation (i.e. a "group by" clause) and return a polygon containing all the points for a particular area code. I'm struggling a little to even find if there are any built in aggregations for the geography data types...

gdal c# readasarray

hi i was using gdal api to read raster files... i found in some places that python version has readasarray i assume this takes the data of the raster file as two dimensional array, is there any similar option for c#, or at least can you show me how to do it? thanks a lot! ...

Developing Geographic Thematic Maps with R

There are clearly a number of packages in R for all sorts of spatial analysis. That can by seen in the CRAN Task View: Analysis of Spatial Data. These packages are numerous and diverse, but all I want to do is some simple thematic maps. I have data with county and state FIPS codes and I have ESRI shape files of county and state boundarie...

Spatial SQL: Most suitable datatype for a square?

I have a spatially enabled database (DB2, in this case). I need to store a large number of squares in a table. Which standard spatial SQL datatype is most suitable? I guess I could use an ST_polygon, but maybe there is a more specialized type which would give better performance better data guarantees (I want to catch it as an error if...

Targeting a Java app at Oracle AND Postgres

Does anyone have any experience with creating database agnostic apps in Java, particularly with Hibernate, and simultaneously targeting Oracle and Postgres databases? In particular I am looking at Oracle Spatial and PostGIS. We want to create a Java based SOA which can be used with both Oracle Spatial and PostGIS back ends. I've used Hi...

Is there a library in plain C that converts GPX to KML, and other geo-formats?

Is there a library in plain C that converts GPX to KML, and other geo-formats? ...

GIS: line_locate_point() in Python

I'm pretty much a beginner when it comes to GIS, but I think I understand the basics - it doesn't seem to hard. But: All these acronyms and different libraries, GEOS, GDAL, PROJ, PCL, Shaply, OpenGEO, OGR, OGC, OWS and what not, each seemingly depending on any number of others, is slightly overwhelming me. Here's what I would like to do...

How to calculate distance from a point to a line segment, on a sphere?

I have a line segment (great circle part) on earth. The line segment is defined by the coordinates of its ends. Obviously, two points define two line segments, so assume I am interested in the shorter one. I am given a third point, and I am looking for the (shortest) distance between the line and the point. All the coordinates are gi...

Algorithm for determining minimum bounding rectangle for collection of lat/lon coordinates

I need some help coming up with an algorithm to determine the minimum bounding rectangle around a set of lat/lon coordinates. It is OK to assume a flat earth since the coordinates will not be too far apart. Pseudocode is OK, but if someone has done this in objective-C, that would be even better. What I am trying to do is set the zoom ...

Oracle geospatials tutorials?

I am very interested in applications of geospatials. Is there is a good tutorial? I am a beginner at SQL, can I work with geospatials through the .NET environment? What should I download to use spatials? ...

Parsing latitude and longitude with Ruby

Hi! I need to parse some user submitted strings containing latitudes and longitudes, under Ruby. The result should be given in a double Example: 08º 04' 49'' 09º 13' 12'' Result: 8.080278 9.22 I've looked to both Geokit and GeoRuby but haven't found a solution. Any hint? ...

PostgreSQL and SQL Server 2008 (DBI-Link)

At work we are having a bit of trouble with spatial support of SQL Server 2008. In SQL Server 2008 we have a big system in production going on, managing a bunch of important stuff. In some of the tables, I have pairs of coordinates and need to display them to ArcGIS and other GIS software. My question here really is: Is it possible to ...

Proj.NET and Sql Server 2008

Hello everyone. I have found this project on Codeplex. http://www.codeplex.com/ProjNET I need to integrate this code with Sql Server 2008, and found a similar project on the Web http://sqlspatialtools.codeplex.com/ The second one can be bound to Sql Server. What do i need to do, to "bind" the first one, the same way as the first? E...

How do I stop rails from escaping values in SQL for a particular column?

I'm trying to manually manage some geometry (spatial) columns in a rails model. When updating the geometry column I do this in rails: self.geom="POINTFROMTEXT('POINT(#{lat},#{lng})')" Which is the value I want to be in the SQL updates and so be evaluated by the database. However by the time this has been through the active record mag...

Maps: Does calculating distance between 2 points factor in altitude?

Does Postgres' Spatial plugin, or any Spatial package for that manner, factor in the altitude when calculating the distance between 2 points? I know the Spatial packages factor in the approximate curvature of the earth but if one location is at the top of a mountain and the other location is close to the sea - it seems like the calculat...

Whats the easiest way to get sql 08 spatial data onto a map?

I've got a DB with a whole bunch of records containing lat and long of points I want to get onto a map. The level of detail I need is down to Australian street level and up to the country level and it can be either pure map data (suburbs, streets, etc) or aerial photos. This is purely for personal purposes and the output doesn't need to...

Spatial Data with SQL Server 2008 & Virtual Earth

Hi all, I am loading the spatial data from Geoconcept Navteq UK Map to SQL Server 2008.In geoconcept the geometry field is, sepparated values of Longitude and Latitude. I have written a one webhandler to connect to database and retrieve data in the form of GML.From that GML ,i am creating one Georss feed.I am displaying on top of virtu...

Looking for Ideas: How would you start to write a geo-coder?

Because the open source geo-coders cannot begin to compare to Google's or even Yahoo's, I would like to start a project to create a good open source geo-coder. Just to clarify, a geo-coder takes some text (usually with some constraints) and returns one or more lat/lon pairs. I realize that this is a difficult and garguntuan task, so I a...

SQL Server 2008 R2 hemisphere limitation

Does any one know if the limitaition on SQL Server 2008 that a geography cannot be larger than a hemisphere (described here) has been fixed/relaxed in 2008 R2? ...