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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I've got a GeoJSON file of administrative borders i.e. state and county, and a CSV file with 12,500+ named GPS coordinates located within the geographic area.

My boss wants me to use the GeoJSON identify the county for each GPS location so I end up with a CSV file (format) like;

Is there any tool that can do this?

Thanks a bunch.
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With AS3 I combined geolocation and accelerometer to direct the iphone, with its back towards a star at the sky. Accelerometer works fine for tilt 0-90 degrees ( directed towards horizon, phone vertical - towards zenith, phone horizontal with screen downwards) but geolocation heading of course flips around 45 degrees tilt and begins to show star direction + 180 degrees. Around 45 degrees tilt geolocation heading becomes very random and I would be very grateful for a suggested algorithm to eliminate the randomness of this phase shift.
Specifically my problem is:

head = event.heading;
head2 = event.heading -180;
 if(head2<0){head2 +=360;}

 if(angleSky>45) {head3 = head2;} else {head3 = head} // angle obtained by accelerometer

Ideally above angleSky 45 the code should choose head3=head2 and that should then be a continuation of the heading below 45. But this is not the case. Sometimes the geolocation heading switches at 43 or 44. Thus what I have tried but not succeeded is to store head  at 42 or 43 and then compare head3 with that. If head3 then is more than 100 degrees difference I tried to use the heading at 42-43. But I have not succeeded. Can it be that the aquisition rate, 50 mS is too fast? Or is this attempt to solve the problem not the optimal model?
Our company has a KML file that when imported into Google My Maps shows the current coordinates of a fishing boat in the North Atlantic ocean. We then embedded this Google Map into a webpage in an iFrame.

We have a problem in that the position of the ship does not auto-update (refresh) on the webpage. We must constantly re-import the KML file into Google My Maps and obtain new code to paste into our webpage. This is very impractical.

Up until about a year ago Google had a service called : Embed KML gadget. Using this tool you only need import your KML once and resulting webpage is always up-to-date showing current GPS positioning.

It's a longshot but can anyone out there help?

Dear Sir ,

I am working on a GIS Data creation application , I would like to have your need for customization .I want that when user open a ArcMap application It will ask for Login window and user need to put their credentials ,then it allow to go inside the ArcMap ,Where I have ArcGIS Service and after accessing these service user will start to digitize the features in both online and offline mode .

If user created the feature and he doesn't have any internet connection while digitizing the features then data store in local table and once internet connection is there it will automatically store in the central server .

I look forward your kind help

Thanks & Regards.

I saw a 360 degree camera the other day and thought they might come in handy for me. Maybe I wold use it while I am giving a virtual tour, for example.

What kinds of things are they good for? And bad for?

They seem impossible to edit...

Is it so the viewer can have a "Google Earth" kind of sensation?


I have an iPhone 6 and hope to find an app or combination of tools to I can use to estimate distance and direction of objects (buildings) that are a mile or three away from me.

given the phone knows its location and orientation, might it be used w/ the camera to plot the location of the object I focus in on?

What's the easiest way to do this? I do not need precision, but just a pretty good estimate.

Its supposed to be a map guider an accurate gps for car by giving the accurate route through roads car must do.

underlined line is what debug shows it as wrong.

any other

using System;

using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Runtime.InteropServices.WindowsRuntime;
using Windows.Foundation;
using Windows.Foundation.Collections;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;
using Windows.UI.Xaml.Controls.Primitives;
using Windows.UI.Xaml.Data;
using Windows.UI.Xaml.Input;
using Windows.UI.Xaml.Media;
using Windows.UI.Xaml.Navigation;
using Windows.Devices.Geolocation;
using Windows.Services.Maps;

// The Blank Page item template is documented at

namespace App75
    /// <summary>
    /// An empty page that can be used on its own or navigated to within a Frame.
    /// </summary>
    public sealed partial class MainPage : Page
        public MainPage()

            button.Tapped += Button_Tapped;

        private async void Button_Tapped(object sender, TappedRoutedEventArgs e)
            BasicGeoposition b1 = new BasicGeoposition();

            b1.Latitude = Convert.ToDouble(startpositionlatitude.Text);

            b1.Longitude = Convert.ToDouble(startpositionlongitude.Text);

            BasicGeoposition b2 = new BasicGeoposition();
Hello Experts,

I am an independent contractor. I make custom reports and maps for police departments. I use Crystal Reports, T-SQL to prepare scripts for handling data, and ESRI for mapping crime, AVL data, CAD data, etc. I have made $45 per hour since 2008. I want to raise my hourly rate - can you give me some ideas about what people charge for this skill set?

Thank you, Chop
I am after some suggestions as to whether it is feasible to know where the mobile phones of our staff are at any particular moment and where they have been in the past so I can replace the expensive rental on GPS trackers in the cars.

* I work with a small electrical firm where each vehicle has a GPS tracking system that is soon to run out of rental contract.
* Staff are all equipped with an iPhone and a Galaxy TabA (can be hotspotted to iPhone)
* Office staff need to know where staff are at any particular time in order to efficiently assign urgent jobs
* Office staff also need to occasionally look to see where a vehicle was on a particular day
* I have no idea what an iPhone can do as far as reporting current position or historical tracking but I believe it can do it so some degree
* Using the iPhone for too much tracking can put a real drain on the battery so what are the options?
* The Tab A has GPS functionality but it's communication options are limited to WiFi
* I may be able to use TASKER on the Galaxy tab to log its position at regular intervals and email it to the office when connected to WiFi

Any suggestions would be appreciated
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I have a problem in GIS coordinates. I have this excel file with unknown CRS

sample data:
source coordinate (EPSG:4994 PRS92)
x: 675282
y: 1217112
    - note (the location of this coordinate should point in Ormoc City, Philippines, because i know where this entity is located)

target coordinate (EPSG:4326 WGS 84)
Lon: 124.6051799°
Lat:  11.0016664°

but when you show it on the map, the coordinates points somewhere near the port area instead of pointing in corner real and burgos streets, Ormoc City, Philippines (should be near this coordinate LON=124.60670952, LAT=11.0056316)

I'm using this for the transformation. Do you have any formulas that i can write in my excel file to convert it properly? Thanks in advance.
Hi there,

I have built a class library (dll) in visual studio that creates an activeX control object to be used inside another container program (engineering software). I downloaded MapWinGIS, which is an "ActiveX Control and application programmer interface ". The API does most of the heavy lifting and I am able to compile/embed the activeX object inside the container, but I am a little confused about how to deploy this onto other workstations...

I would think its more complicated than simply dragging the project folder over to the workstation. I have done some elementary research on this topic and some people have suggested that I will have to install MapWinGIS onto each workstation at the very least to ensure that all the referenced files are present and then I would have to register the class library itself using either gactutil, regasm /codebase or regsvr32.

I am just not sure, any advice would be greatly appreciated.
Is there anyway I can hook up a garmin gps I have via USB and have it used for location services on Windows 10?
We try to use the location and Siri to remind us of certain things when leaving the office.  However, no succes.  That said, how can we use Siri successfully to remind us of certain things when leaving the office?  Also, how accurate will the location be? (For example, will the reminder be activated as soon as we leave the door or 200 feets of current location the reminder will be fired?)

Thanx in advance!
I made an outline in google earth a few months back and now I cannot delete it.  I cannot get the mouse to grab it.  Any ideas?
Is there anyone here familiar with SKiaSharp or SKia (a search here found no mention of this software)?  Basically, I take the survey lines from a survey, and draw the outline of the land, using SkiaSharp\DrawPath.  This works fine for straight line surveys, but it cannot handle lines that are not straight.  I have posted in the Xamarin\Skiasharp forum..., but have not had any replies.  And, I cannot find any examples\samples on the subject.  If you think that I should be posting elsewhere, please point me in the right direction.

  Google chrome GPS location could not be determined.Some times works fine.otherwise not working.Please suggest me any other for access location in google chrome browser.We want goole chrome browser access gps location.

  Every day we are facing this issue in our PC's.Work fine in LAptop & mobile chrome browsers
Environment :
1. Linux, C++
2. UM7 Device contains (GPS latitude, longitude, Altitude, Accelerometer, Gyrometer).

I am getting below data using UM7 device fitted on moving vehicle :

    GPS latitude, longitude, Altitude.
      Accelerometer (x,y,z)
        Gyrometer (x,y,z)

        How can I calculate vehicle movements (left, right) using
        Latitude, Longitude & Altitude ,Accelerometer, Gyrometer data ?

        How can I calculate Speed ?

        Any suggestion / help is highly appreciated.
        hello ,,

        i want to know if it possible to track a phone by UDID
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        My app has been VERY slow of late, when I looked into it, it appears there is a massive memory leak It climbs up to 2gb and crashes

        We used took three Heap Snapshots on chrome developer tool,

        one during login (when the google maps are loaded) another after everything loaded, and another when signalR pushes the data.

        We compared the three snapshots, Open Layer stuff had many detached dom trees and kept building up. Therefore, Open layers has contributed to the memory leak of the app greatly.

        Among the functions that we suspected caused the memory leak are:






        After some few minutes the app crashes due to large amount of the memory used. The question is, how can we deal with this situation so that there are no memory leak in the app that is caused by the Open layers.

        Also, when clicking anywhere on the app even in the pages where maps are not loaded, Open layer function are called. When Click events get fired they in turn calls the Open Layers functions.

        I'm looking to consolidate two google script functions into one:

        functions are:
        1. getLongLat - this looks up the Long & lat positions given an address
        2. GetCityL2L1Country - this looks to city state county and country given long/lat

        example Google sheet using these functions:

        I want one function eg GetStructuredAddress() to return and array of all 6 items, ideally using as few requests as possible (as google limits free requests)

        var geocoder = Maps.newGeocoder(),
            cache = CacheService.getScriptCache();
        function GetCityL2L1Country(latitude, longitude) {
        //  var latitude = 51.69048,
        //      longitude = 5.29362,
          var cacheKey = latitude + "+" + longitude,
            cached = cache.get(cacheKey);
          if(cached !== null) {
            return JSON.parse(cached);
          var result = geocoder.reverseGeocode(latitude, longitude),
          //First response is the most specific
              response = result.results[0];
          if(response === undefined) {
            return "??";
          function g(fieldName) {
            for (var i = 0; i < response.address_components.length; i++) {
              if(response.address_components[i].types.indexOf(fieldName) != -1) {
                return response.address_components[i];
            return {"long_name": "??"};
           rValue = [[ g("locality").long_name, g("administrative_area_level_2").long_name,  g("administrative_area_level_1").long_name, 

        Open in new window


         I'm looking for recommendations for a small device like the tile that had a rest API.


        This is a follow-up to this q which successfully looks up long/lat location given an address:

        I also need a function to obtain the City, State, and Country from an address, is this possible?

        eg a 3 cell array output from GetCityStateCountry(myaddress)
        or better yet expand the previous answer to a 5 cell output GetLongLatCityStateCountry(myaddress)

        Alternatively a database function that can obtain this from the long/lat info would be ok but I'd prefer not to have to go that route.

        Dear Experts,

        Can anyone advise me of a way to track my phone using GPS even when the mobile phone does not have internet access.

        i have searched a lot on internet but they all need internet access to update the servers.

        Thanks and Regards
        I need to use my Tab 4 to drive Uber, since my iPhone 6 will not load the Uber Partner app.

        So, I use my Verizon Wireless MI-FI modem w/ my Tab 4.

        But the GPS is terrible!

        Is this due to the age of the Samsung?

        It's the only tablet that fits in my pocket!

        It was already old when I bought it, but I bought it for convenience.

        What can I do to get the GPS to work well on my Tab 4??

        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