I'm using MySQL GIS and Spatial Extensions. I've a table with "circular" regions described by latitude, longitude and radius. I need a query to get all the rows whose region include a given point defined by a latitude and a longitude. The "circular" regions can intersect and therefore the point can fall in more than one region. ...
Hi I am using mapdotnet services for our gis application to load the shape files and this mapdotnet service want the proj4 details and that getting from the spatialreference.org but for this proj4 details is blank. any other way to get it. Below is the .prj of the shape file- PROJCS["NAD_1983_HARN_WISCRS_EauClaire_County_Feet",GEOGCS...
I want to display a signal bar for a GPS device using .NET CF. I'm able to read NMEA data and get the SNR signals. But they are a number of satellites with some active and some inactive with various SNRs. I thought about getting average of total SNR but it won't give a accurate value as three strong signal satellite is enough for GPS fix...
Hi folks I tried posting this question earlier but was unsuccessful so I'm trying again I imported a shape (set of points) file into postgres and have a table (hist_info) with additional data also in postgres. I tried creating a VIEW with data that I need from each files but for a reason I can't figure out as to why my GIS layer (creat...
Hi, I have two TINs (triangulated irregular network) of a terrain. First one (TIN1) is the original one, let's say with X number of points. And the other (TIN2) is simplified (the number of points were reduced by some decimation algorithm) one where let's say it was build from Y points, where X>Y. Now, how could I do the following compar...
I just started using PostGIS & Postgresql and everything is running smoothly for the most part. When I try to find which MULTIPOLYGON s a POINT lies in I'm getting stuck. I have two separate points that I am certain lie inside one and only one shape that is of MULTIPOLYGON data type in my database. They are not the same points and the...
I have an excel spreadsheet I want to convert to an ESRI shapefile programmatically. It contains X and Y coordinates in two columns, as well as a variety of attribute data in other columns. The spreadsheet is in excel 97 format (i.e. not .xlsx). I would like to be able to convert this to a point geometry shapefile, with each row's x,y...
Hi guys! I hope you could help me here, thanks in advance! Well, I'm taking a GIS class and we are tasked to build a GIS app, just a simple one, that should be deployed on the Web. I have a bit of experience in using GIS stand alone app. So in essence, I have a basic understanding of how GIS works and on. Well my problem is, I don't h...
I'm developing an OpenGL application. I need to have a model of planet earth spinning around (with the waters in blue, the land in green). My question is not dealing with the OpenGL / graphics ... but with the data. Where can I get this data? (Of the boundaries of the various countries). Bonus points if you also know where I can get ele...
Hi All, Lately I have seen some cool examples of mapping in R and wanted to give this a shot. I currently have ArcView at work, but my spatial join is not working correctly (most likely user error). Objective: I need a list of countries and what World Region they belong to. I have two layers (one country detail, the other region de...
Here is my model definition for a model in a GeoDjango app (with a PostGIS 8.4 database) meant to represent a Chicago neighborhood boundary: class Neighborhoods(models.Model): objectid = models.IntegerField() pri_neigh_field = models.CharField(max_length=3) pri_neigh = models.CharField(max_length=50) sec_neigh_field = mo...
Hi, I'm struggling with a problem with some GIS information that I am trying to put into a KML file to be used by google maps and google Earth. I have SQL database containing a number of surveys, which are stored in lines. When all the lines are drawn on the map, they create a grid. What I am trying to do is work out the centre of th...
Hi, I'm learning to create a WMS service using MapServer and after that I want to develop a PyQt desktop application which will access it. I don't know what is the best way to do that because I have seen a lot of web solutions but it's not what I'm looking for. Neither I know if there are libraries that can help me. Can you give me som...
The Australian Electoral Commission has free ESRI and MapInfo formate GIS layers of Australian electoral boundaries for download. I want to convert this data to a thumbnail polygon image using a free tool. ...
Hello All, I'm just getting into GIS right now with a new project at my work - so I'm still kinda new at all of this. I'm using GDAL to work with the TigerLine Shape files from the previous US census land survey. Within these files you can find (among other things) polyline sets that describe lat/long position of roads and you can fin...
How can I get the installed GDAL/OGR version from python? I aware of the gdal-config program and are currently using the following: In [3]: import commands In [4]: commands.getoutput('gdal-config --version') Out[4]: '1.7.2' However, I suspect there is a way to do this using the python API itself. Any dice? ...
I'm working on a transportation model, and am about to do a travel time matrix between 5,000 points. Is there a free, semi-reliable way to calculate the travel times between all my nodes? I think google maps has a limit on the number of queries / hits I can achieve. EDIT I'd like to use an api such as google maps or similar ones as th...
i have 3 shapefile ready in a map file, and rendering it on mapserver. what i need is to and these layer overlay one over the other.how can i do this ...
I want to better understand what is required in order to implement a geo-spatial (aka proximity) search. I'd appreciate clarification on the following: Beyond the latitude & longitude for corresponding zip codes, what if anything, is required? Can anyone recommend any resources (books, websites, etc.) for understanding the formulas ...
I am looking for some kind of earth model that at run time can pick up some data from an xml file and display it on the earth based on lan or lon etc.Is there something like that ? Any OpenGL or flash where I don't have to do coding just feed the thing.Can someone shed some light on available ways to accomplish this.Something on the line...