hi Friends, I want to edit the corresponding text/numeric data type columns of a vector through openlayres, when a user click/mouse over a vector. like, http://dev4.mapgears.com/bdga/bdgaWFS-T.html# any tutorial page for how to do it? I gone through it , it was difficult for me to understand from its js codes. -posted in gis.stackexch...
I have GPS track data from a logging device, in GPX format (or any other format, easily done with gpsbabel). I also have non-GPS data from another measurement device over the same time period. However, the measurement intervals of both devices are not synced. Is there any software available that can combine the measurement data with the ...
Hi! I'm doing a project using OpenStreetMap and OpenLayers. Currently, my task is to insert the data from the OSM file that I have to a PostgreSQL. When I checked out Osmosis (the tool for transferring data from the OSM file to the database), it says there that, in one example, "Import a planet file into a local PostgreSQL rails port dat...
What is the most efficient way one would go about retrieving the U.S. Postal zip code for a street address using Python? Is this something that is even possible? Preferably, something that includes a local database as oppose to a remote API call of some sort. Thanks in advance for any help one may be able to offer. ...
I have the following: An image - a hand drawn map - of an area of roughly 600x400 meters. The image is drawn on top of Google Maps tiles. The latitude/longitude (from Google Maps) of the corners of this image. Or put differently, I have the north and south latitude and the east and west longitude of the image. A latitude/longitude coor...
As part of a mapping application, I am implementing a crude sort of tiling. I am looking for an efficient way to know which tiles need to be loaded according to the current map view port. In order to do that, I thought of taking the point in the center of the map (for example) and loading the tile for that point. I need an algorithm f...
Suppose you are given an image of the earth's surface and that it is stored in the database as a polygon defined by the latitude/longitude pairs of its corners. Now suppose there are millions of images covering the earth's surface that are also stored similarly. What is a good strategy to find those images which intersect with your give...
I want to write a GEOTIFF, with all the geographic metadata in Java. Which library etc. works best for this purpose? ...
On large graphs like 2M node road network, dijkstra can not solve shortest path problem in suitable time. We need to shortest path query execution time under 1 second and I am implementing arc flag way to make dijkstra fast. Is there anybody know about how to implement arc flags preprocessing and query. Preprocessing of arc flags has som...
I am trying to read a binary file and parse the bytes I have the white paper spec on Shapefiles to know how to parse the file, however I cannot seem to find the correct functions in ColdFusion to handle reading bytes and deciding what to do with them. <cffile action="READBINARY" file="mypath/www/_Dev/tl_2009_25_place.shp" var...
hi all, this is an oldie, but i cannot seem to find a solution. When i want to do an st_transform on a 900913 coordinate to a 4326 system, the y coordinate shifts. example: SELECT AsText( Transform( Transform( GeomFromText( 'POINT( 449760.25168159 6790560.4594059 )', 900913), 4326 ), 900913 ) ) here the original 900913 stating p...
I need to analyze a few million geocoded records, each of which will have latitude and longitude. These records include data of at least three different types, and I will be trying to see if each set influences the other. What database is best for the underlying data store for all this data? Here's my desires: I'm familiar with the DB...
I'm looking for a good way to create a moving map app on an semi-embedded device, comparable to a netbook. The source images are 400MB tiff files with associated world and projection files. The current approach I've taken is to create a tiled dataset for the desired zoomlevels in OSM map format. It works, but uses up way too much disks...
I'm building a webapp that will need to provide some real-time tracking information overlayed on to some maps. My requirements are fairly simple: I need to take a series of lat/long co-ordinates, and overlay simple markers at those positions with a small bit of associated textual information (ie, just a label and/or tooltip at the mark...
Hi guys. I've been using PostGIS in a long time now but never had to use the LINESTRING geometry ... yet! :) Here's what I would like to do : I have a table of linestrings (representing streets of a given city, SRID 3395) and I would like to find the nearest linestrings to a given point (GPS position, SRID 4326). The solution I found ...
I have two sets of "lines" drawn using a mapping API in the form of (lat,long) pairs. Given 2 of these lines, how can I compute the (lat, long) of their intersection (assuming they intersect)? ...
Hi overflowers!! Hope you help me... I've been at this for the past 2 days and have to admit that I'm stumped. The OS I'm on is Ubuntu 9.10 Karmic. I successfully installed and tested Mapserver. For my class project, I have a php script that I am using to create a layer see below.... The error I get when run the script on a cmd line...
Hi quick question, has any heard of any GIS IMS capability program that will allow multiple displays of data to be geo linked. For example, when one pans on one view it will automatically relocates the extent on the corresponding linked viewer. Thanks for any help. ...
I have a million points and a large shape file 8gb which is too big for to load into memory in R. The shape file is single-layer so a given x,y will hit at most one polygon - as long as it's not exactly on a boundary! Each polygon is labelled with a 'severity' - e.g. 1,2,3. I'm using R on a 64-bit ubuntu machine with 12gb ram. What's...
Hi..I am trying to see if a given pair of (lat,long) will fall within a circular region. The centre of the circle is known (lat,long values) as well as the radius. The approcah I have used is: Calculate the distance between the centre and the given lat/long using Haversines formula. Formula: a = ( sin(delta_lat/2) )^2 + cos (vp_Curr...