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GIS/GPS Programming

The Global Positioning System (GPS) is a space-based global navigation satellite system (GNSS) that provides reliable location and time information in all weather and at all times and anywhere on or near the Earth when and where there is an unobstructed line of sight to four or more GPS satellites. A geographic information system (GIS) or geospatial information system is any system that captures, stores, analyzes, manages, and presents data that are linked to location(s). In the simplest terms, GIS is the merging of cartography, statistical analysis, and database technology.

I created a geologic map mashup with Google maps, GeoServer, and polyclusters.....

I'm attempting a different approach (updating the GeoServer layer style) but can't get anything to work...
 I'm using one layer in our GeoServer, AGS:GEOLOGY_500K, which has a default style.  When I try to override the style like this it doesn't work....
return GEOSERVERBASE + "/geoserver/wms?" + wmsparams.join("&") + "&layers=" + Geo500K + "&bbox=" + lUL_Longitude + "," + lUL_Latitude + "," + lLR_Longitude + "," + lLR_Latitude + "&sld=" + GEOSERVERBASE + "/geoserver/styles/default_polygon.sld";

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When I try to clear the GeoServer layer like this it doesn't work...

Go to
and select Mississippi Embayment and Gulf Coastal Plain from the Regions, then select Channel Meander from the Formations.  The style of the Geoserver layer should update with a black outline around the Channel Meander formation, but it doesn't work.
I'd like to change the style each time a formation is selected.   Am I going to have to do this each if statement when a formation is selected  .....
	if (fmLbl == 'qcm') {	
		map.setCenter(new google.maps.LatLng(34.75, -92.202));
overlayMaps =[

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Hi Experts,

As part of work I am carrying our for a government project, we have been asked to provide the following via the website:

The Development and planning office had GIS based maps for the city of Lusaka to the parcel level (specific Plot).
-      They would like to have these maps available online in an interactive way to be able to show, to the parcel level, the different constituencies and townships, types of land (commercial or small holding) and their availability using different color codes.

Need suggestions and help on implementing such a solution onto the website built in Wordpress.
Hi Experts,
We have a list of potential customers in Excel that we have given to our sales guys. I would love for them to be able to click on the address portion on their iPhone and it automatically open in either Google Maps or Apple's Maps app. Is this possible? I can't seem to find much about it online. Thank you for any help or guidance.
I have a group of points, I want to create multiple rings that connect a maximum of five points at a time with the shortest distance possible between rings. I was searching specifically ESRI ArcGIS tools and was having trouble finding the best tool for this job. I was wondering if anyone had a suggestion for a method or Tool to use that would make this task possible. Here is the group of Points I am working with.

Point cloud
I have two JSON files, one is a GeoJSON file and comes from a local source. It contains geometry for the counties as well as the County name and FIPS/GEOID identifiers.

The other JSON file is actually one of several topics that the user can request. This JSON file is hosted remotely and contains the FIPS/GEOID attribute as well as data such as population, tax revenue, acres of farmland etc.

What I want to do is set it up so that when the page first loads just the GeoJSON is loaded. The user selects which topic they are interested in viewing.

This data should then be somehow combined so that it can be used by the map (as well as some charts) on the page. So my question is how do I combine this data together?  Or do I keep it separate and when creating the chart I have to do two lookups?

An example of a combined  structure might look like this

"type": "FeatureCollection",
"features": [
    "type": "Feature",
    "properties": {
      "FIPS": "19119",
      "COUNTY": "Lyon"
       "attributes": [
         "population": "95000",
          "cropAcres": "204560",
          "malePop": "47034"
    "geometry": {
      "type": "Polygon",
      "coordinates": [

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I’m working for a software company and we are designing a new software solution for one of our customers. In this solution road maps and routing will take a serious part.

Based on the ArcGIS API documentation I am quite sure most of our map related requirements can be handled with ArcGIS. Some details are still not so clear to me yet.

Now the question:
A centralized system periodically receives positioning data from moving cars. It needs to track the car’s actual route. As you know GPS data is not very accurate. Just finding the route a car took by looking at each single positioning data separately and connecting these measures points to a route, might have funny resulting effects. These resulting routes will be incorrect especially in areas where roads are close together or are overlapping (bridges, tunnels, etc.). The route information so far and the road map have to be taken into account to figure out the most likely route a car took.
Even if the transmitted position information suggests a car is currently on the road underneath a bridge, the car would most likely not have jumped of the bridge if the previous position was on it. The time difference between the measures makes it impossible to find a valid route from position on the bridge to the suggested new position underneath the bridge. This means the measure of position underneath the bridge is not accurate and has to be corrected to be on the bridge again.

Does ArcGIS provide such functionality to …

Please suggest me sites related with GIS (geographic information system) mentioning the process,the pre-requisites and the basic knowledge required for creating a gic project.

Since i am new to this term i had gone through wiki but unable to find the above mentioned.

I have a form with five fields that is bound to a table "tblMappoint". I have button on the form that when pressed should open Mappoint and plot the data points using address, city, state, and zip. I am getting a VBA compile error: Method of data member not found on the line "rs.Edit". Any help in resolving this would be appreciated.

Here is the fields in the table
Address = short text
City = short text
State = short text
Zip = short text

Here is the code behind the button

Dim APP As MapPoint.Application

Private Sub Geocode_Click()

  Dim MAP As MapPoint.MAP
  Dim FAR As MapPoint.FindResults
  Dim LOC As MapPoint.Location
  Set APP = CreateObject("MapPoint.Application")
  APP.Visible = True
  Set MAP = APP.ActiveMap
  Dim rs As Recordset
  Set rs = CurrentDb.OpenRecordset("SELECT * FROM tblMappoint")

  Do Until rs.EOF = True
    Set FAR = MAP.FindAddressResults(rs("Address"), rs("City"), , rs("State"), rs("Zip"))
    Set LOC = FAR(1)
    rs!MP_Latitude = LOC.Latitude
    rs!MP_Longitude = LOC.Logitude
    rs!MP_MatchedTo = GetGeoFieldType(LOC.Type)
    rs!MP_Quality = GetGeoQuality(FAR.ResultsQuality)
    rs!MP_Address = LOC.StreetAddress.Value

End Sub…
Dear expert,

Hi am planning to develop iPhone  and android application for  my government agencies, to change the address online.

The issue is the authentication, and notification issues.

Every government has their own website and application in apple store and google store.

and customers have username and password for each services.

The procedure now if the customers need to change the address he or she have to login in to each services to do the changes which will take them more than 30 minutes . Most of the customers do it manually by visiting each agencies

Am planning to make it easy simple, saving time and secure , to  create one application to update customers address (cell phone, land line,p.o.box and location coordinate) when they move from location to another.

I check out USPS.com and updater.com it is different will not work in my country.

So I come up with idea to create one application for customers to register first then add the services want to change.

Trade licenses
Health authority
Driving license

From my application after register then add the service like to change the address.

I have to integrate my application to each service to update the address directly on  Their database  . Regard the notify them via email won't work .

For example:

I have to register with username and password , then add electricity authority service I have to log in from my application, then trade license authority I have to …

Over the last few weeks, I've added some cycling tracks to Google Maps using Google MapMaker.

These have been published and I can see them on any computer.

When I look at Google Maps on my Samsung S2, these new tracks are not there. I've tried uninstalling the updates and reverting Maps to the factory original version and I've emptied the cache many times but the new tracks do not appear.

Does the Android road and track library only get updated when a new version of the app is released or am I missing something?


I found and tweaked the Google Map example below which shows multiple infowindows for multiple locations. Question is, how can I modify this code to show an image in each infowindow?

Many thanks

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">
    <title>Google Maps Example</title>
     <script src='http://code.jquery.com/jquery.min.js' type='text/javascript'></script>
<script type="text/javascript" src="http://maps.google.com/maps/api/js?sensor=false"></script>
<script type="text/javascript">
var infowindow = null;
    $(document).ready(function () { initialize();  });

    function initialize() {

        var centerMap = new google.maps.LatLng(52.258175, -7.11);

        var myOptions = {
            zoom: 13,
            center: centerMap,
            mapTypeId: google.maps.MapTypeId.ROADMAP

        var map = new google.maps.Map(document.getElementById("map_canvas"), myOptions);

        setMarkers(map, sites);
	    infowindow = new google.maps.InfoWindow({
                content: "loading..."


    var sites = [
	['Mount Evans', 52.253238,-7.115563, 4, 'This is Mount Evans.','images/Sunset.jpg'],
	['Irving Homestead', 52.253238,-7.125563, 2, 'This is the Irving Homestead.','images/Sunset.jpg'],
	['Badlands National Park', 52.253238,-7.135563, 1, 'This is Badlands National 

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I have a map created using OpenLayers and now i am working to get a popup configured correctly.  I have a feature attribute which contains a file name for a PDF.  When the feature is clicked I would like to be able to create a link to the filename but I am having problem getting the link to work.  Below is the content for the popup but it does not create the link:

"Owner: " + feature.attributes.OWNER + " <br> " + "<a href=" + feature.attributes.AB_PDF + ">"
I have multiple individual large spatial datasets, grids/rasters around 80Gb.  What is the best way to deal with delivery of this information online.  The proposed method is to allow the user to select an area eg rectangle on a google map interface. The rectangle geographic extent coordinates are used to issue the subset instructions and generate an output image of the area of interest. Instead of processing the image extraction from the large dataset I was looking at a solution that stitches image tiles together at resolution based on the area of interest. My questions relate to the following areas;

1. Type of OS / Scripting Language or Framework of the server (eg Linux/Python Windows/.NET (my primary technology)). Pls note CLOUD systems are NOT an option.
2. Perform Subsetting on a remote server or Supply Subset PNG8 images on the main server that get stitched together.
3. Open source systems that already achieve this.

Geoserver appears to be a potential solution.
Hi, I've got this .NET app written to connect with GPS devices. Any emulators / simulators out there to simulate GPS devices ... since GPS connection can be erratic indoors??

I've googled and found FakeGPS as an option (http://msdn.microsoft.com/en-us/library/bb158722.aspx). Anyone used this before? Anything better?

Please provide me with a list of the best Garmin GPS traffic navigators with real time traffic conditions.
Attached is sample code found on the internet. I cannot get this to work; getting a lot of false positives and misses. I have access to a PeopleNet database that provides Lat/Lng defining vertices for a given Geofence.

How can i get this to work. Do the lat/lng points for the GeoFence need to be sorted in any particular order before I run them through the algorithm?? I suck at Geometry.  ANY HELP would be greatly appreciated
I'm driving along with my GPS on my dash and I notice something (either on the map or out the window) that I want to divert to.

I want to touch the place on the GPS map and change that touch-point to my new destination.

What GPS has this capability?

I have a Python script with two classes, each representing a combo box.  Besides __init__, each class contains an onSelChange() event which, as the name implies, performs an action when the combo box selection changes.  

The first class, called Layers, creates a string variable called selLyr.  What I would like to do is pass the value of that variable to the second class, called selectMethod.  The relevant parts of the attached code are:

1) Layers -- onSelChange() event:  selLyr is defined based on the user's choice.

2) Layers -- two() method: returns selLyr to the selectMethod class event.

3) onSelectMethod -- onSelChanges() event: I'm trying to retrieve the value of selLyr after it was changed in the Layers class.  As I anticipated, both methods that I show here (xa = l.two() and xb = Layers.selLyr) produce the "Default" result, not the updated value of selLyr.

A more promising approach would be to create a static value for selLyr.  I would first pass the value down from the Layers -- onSelChange() event, then call it back when the
onSelectMethod -- onSelChanges() event is fired.  I've tried doing that using a global module, but am just not getting the hang of it.  

Thanks in advance
good site to download google earth layers
Hi Experts guys,

I have a local html page holding a google map to display some markers and infobubbles.  The data are pulled up from a json file.  Everything works fine in our development and testing environments, but now after releasing the product, 2 of 6 installations are not showing up the map properly.  It seems the script stops working after the first marker is created (when it tries to create the associated infobubble).

We have tried everything from playing with security setting in IE (Internet Security Zone and Advanced settings), folder permission, enhanced security, replacing script files for fresh one, but nothing seems to work in that particular machines.  We can’t reproduce the exact same error in our lab and we have limited access to the client's machines.

I use MOTW to run the html page in the Internet Security Zone.  I played with settings in this zone and I found the only one affecting the map is ‘Active Scripting’. If ‘Active Scripting’ it is disabled the html page just show up a blank page (which it’s not the same error we are trying to reproduce).

Attached please find the script files involved in this case.  (I just remove our own google API v3 key).

Hope someone could point us in the right direction.


Knowledgeware Development Team
We want to map out the roads we've been to and put out our flyers. On Google I typed in a street just now of where I want to visit tomorrow... I also want to somehow MARK that entire street (kind of like Google did in the attached screenshot) highlighting that I've been on that street so I don't hit it up again OR I can stop by streets in that area.

There has to be a way to do this...

Dear All,
We need to create Application for flood warning and water flow  simulation. Could you please advice which components we can use to create such application and do the simulation on 3D maps.
thanks for your cooperation.
ArcCatalog shows that I have a ~$NAMEOFFILE.xlsx in D:\

I receive the error "Failed to connect to database. General function failure External table is not in the expected format." when I try to delete it. The problem is there is no NAMEOFFILE.xlsx that shows in Windows Explorer or the command prompt (hidden files are shown). I am able to copy the file for some reason, but I'm just trying to figure out how to get rid of the file once and for all.

This problem has persisted from 10.0 to 10.1

I am trying to add a right click event to the google maps.  I cannot see alert with the geocodes.
I am not sure what to change.

var map;

var directionsDisplay;
var directionsService = new google.maps.DirectionsService();

function initialize() {
directionsDisplay = new google.maps.DirectionsRenderer();
  var mapOptions = {
    zoom: 8,
    center: new google.maps.LatLng(-34.397, 150.644),
    mapTypeId: google.maps.MapTypeId.ROADMAP

  map = new google.maps.Map(document.getElementById('mapsGoogle'),


 google.maps.event.addListener(map, 'rightclick', function(event ) {
         var lat = event.latLng.lat();
         var lng = event.latLng.lng();
        alert("Lat=" + lat + "; Lng=" + lng);

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I have a bitmap in memory that I would like to load as a raster to PostgreSQL.

An unfavorable option is saving the bitmap to file and then use raster2pgsql, but as we
have several cameras that produce images at high rate, we can't afford saving them to files just for sake of insertion to the DB.

I'm looking for a solution for loading the bitmap directly from memory. Any suggestions?

I'm using PostgreSQL 9.2 using PostGIS2.0 on Windows 7.
The images are plain gray level, if it matters.

GIS/GPS Programming

The Global Positioning System (GPS) is a space-based global navigation satellite system (GNSS) that provides reliable location and time information in all weather and at all times and anywhere on or near the Earth when and where there is an unobstructed line of sight to four or more GPS satellites. A geographic information system (GIS) or geospatial information system is any system that captures, stores, analyzes, manages, and presents data that are linked to location(s). In the simplest terms, GIS is the merging of cartography, statistical analysis, and database technology.

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GIS/GPS Programming