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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 am reading the GPRMC values, all is well.  The date is correct, but the time is incorrect.  It seems to be some sort of sequential counter instead.
restart the code and it resumes at:
175634.000   -- the very first hour, minute and second is correct then...
175635.000  -- the loop is about 5 seconds, so it should really say 175640.000
175700.000 -- so the counter looks like seconds!

Puzzling and concerning because I need to know at exactly what time the GPS coordinates where taken.

What am I missing?
Thank you.
I'm curious as to the best javascript way to include a simple GPS map location portrait of the current device location into a .io app.
Recently been doing a lot of running training and been tracking my runs using a Fitbit Charge 2 to upload to Strava. Charge 2 only has connected GPS rather than built in so I have to carry my phone (Samsung S6) with me to get the GPS tracking.

I have noticed that on a number of occasions the tracking recorded is somewhat out of kilter with the route I know I took. If you're able, take a look at the Strava link below for an example.

Strava Activity

If not able to see the Strava link maybe the picture below will show the issue.
Strava map
If you zoom in on the route you can see for example the sections through Charlton Hayes and Catbrain are quite wiggly, those roads are virtually straight and I certainly didn't wiggle along it like a drunken sailor as the GPS track would suggest. Likewise in the top left part of the route, there is a section where it looks like I broke off the road into the woodland before coming back to the road; I didn't. There are other sections where the GPS track wanders away from the road that I know I took. Where it cuts corners I guess its because I lost GPS signal briefly and it has just joined the points where I lost and regained signal.

I know GPS is dependent on a number of factors, visibility of satellites etc, but this particular route was on a nice clear evening with very little cloud cover, there are sections through trees but some of those are more accurate than the open …
Hello Everyone
This is not a programming question but am looking for an Android App.
An app where I can enter lat lon or address and a compass will point me to that position. It does not need any navigation. Just an as the crow flies direction pointer.

Thanks much ...
I am using Leaflet.js , OpenStreetMap & Angular to display a map. Does anyone know how to implement the equivalent of Google Map Satellite View on this using a free library or plugin ?

 Thanks in advance.
I am working on a project that tracks multiple vehicle, golf carts, bikes and people at the same time ... I know I can buy system but I have to build this myself .... Im designing the REST API to accept the data and put it in the database ... every 10 sec I iterate through the database using the latest timestamp.... The question I don't want to built GPS trackers(Ardrino) ... does anyone know of a fully programable tracker for sale on the market that I can program to send data to my site (gps data) ...thanks in advance
I'm posting on behalf of a member organisation with 1,000 members, mainly in the United Kingdom but also internationally. I have exported the home post code of all members to CSV, and used it to create a Google MyMaps map, with a dot for each member's post code. I want to embed this map on our public website, because when people see how many members there are, it might encourage more to join.

However there are privacy concerns, and I have sought advice from ICO (the GDPR regulator in the UK) that it might fall below our members' expectations, because there are some post codes in rural areas where there are only a few houses, therefore this could potentially count as "personally identifiable information".

Therefore I've been looking at various options. First is a heat map, rather than dots. However, from this it will be difficult to say just how many members there are.

Second option is to remove the last two letters of the post code, i.e. "L31 5" rather than "L31 5AA", which would show the dots in a more general position. However since our members tend to be focused in specific regions of the country, this would greatly reduce the number of dots on the map, therefore defeating the object somewhat.

Another option I've heard is limiting the zoom level of the map, to stop being able to see buildings for example. This is the best option I've heard so far, but I'm not sure if it's possible with Google MyMaps. I've seen that this is possible with the Google Maps API, …
I have created the following two functions inside my JS file (which will be used in PhoneGap/Cordova) and I have put them outside of the main JavaScript class:

 *@description Returns the latitude of the current location
 *@return {float} a latitude
function getLatitude() {
  return position.coords.latitude;

 *@description Returns the longitude of the current location
 @return {float} a longitude
function getLongitude() {
  return position.coords.longitude;

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Why is it, that if I put this into my HTML page, I can get the coordinates - but when I call these functions from within JavaScript, I get an error saying that position is undefined?

What is a workaround so that I only get a latitude or longitude?
Please recommend a Perl script that will return the latitude and and longitude for an address.
Please explain the pros and cons of signing up for a google api account to use their geo code api.
Are there any alternatives to google for obtaining a latitude and longitude for an address ?

Jim West
I am developing my first application with Apache Cordova and I need some assistanstance with the Open Street Map object. I am sending a request to the Open Street Map to get Lat/Lng of a location. I chose Manchester UK and I received the following JSON back:

In order to do this, I set to share a taxi (it's a taxi sharing app) first and then I click on Update Map.
This is the code for UpdateMap:

     function updateMap(address){
        var onSuccess = function(position) {
          var div = document.getElementById("map_canvas");
          div.width = window.innerWidth - 20;
          div.height = window.innerHeight * 0.8 - 40;
          // change the zoomin level
          if (address != undefined) {
            // TODO 2(a) FR2.2
            var endPoint = "https://nominatim.openstreetmap.org/search/" + address + "?format=json&countrycode=gb"
            $.get(endPoint,function(e) {[embed=file 1418190][embed=file 1418191][embed=file 1418192]
              var location = e;
                lng: location.lng,
                lat: location.lat

          } else {
              lng: position.coords.longitude,
              lat: position.coords.latitude
        var onError = function(error) {
            "code: " + error.code + "\n" + "message:

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I have a standard shapefile.  It contains many shapes with their attributes.
I have a list of GPS coordinates that I know for sure are within the area of that shapefile.
How -- preferably with Python -- can I supply the lat/long and get an handle to that shape?
I tried to find exampl c# codes to get Geo Google API and response address.
I have Lat/Lng in my database and try to get the address response back.

Does anyone know if there is a place to get a FREE XLS, CSV or other file format that will allow me to get Countries (US or North America is fine) States & Counties so that I can link it up to some data I have.

If I could get States, Counties, Cities, Zip Codes, Latitude & Longitude even better. I have been to Data.gov, US Census but not really seen a clean or relatively clean set of data that would help me with a project. Does anyone know where I can get that? Please advise. Thank you.
I browsing ESRI.COM website to try to understand the current GIS solution. I couldn't find where the instruction for ArcSDE (Spatial Data Engine) is.
Is the ArcSDE product being deprecated/retired? or it is just hiding some where?
Thank you!
What FREE Android Phone tracking location AT&T APP do you recommend so I can find where my child is currently at if needed ?

 1. https://mobile-tracker-free.com
 2. etc ?
How to convert Polyline Z to normal polyline
How can I indicate to my iPhone X that I am walking (and not driving) while I am using the built-in GPS map services to provide me with turn by turn directions?

This is especially important since I visit a lot of towns that have one-way streets.
Need iPhone app to track my location

I need to sell on the road and sometimes need a reminder which stores I visited. So, a map if where I went each day would be helpful.

What options do I have?

Is there location data already on the phone I can use?

My Galaxy Note 4 (already updated to latest Android) tends to lose
connectivity to GPS (even though the connection to cellular/mobile
data network seems to be intact) while driving for 3 to 30 secs.

I'm using Waze.  The disconnection can happen even on a bright
sunny day (ie don't have to be cloudy/rainy days) or in open
highway (ie not while going through tunnels).

The same SIM card was previously used on my Galaxy Note 2 for
for almost a whole year previously & I never had this issue.

Is this a known issue with Note 4 or the Telco ?  Maybe one way I
can test this is to use the Note 4 as a hotspot (tethering) to an
iPhone & test to see if Waze/GPS  disconnects intermittently:
map is still there but there's a red alert message that 'connection
to GPS is disconnected' at the top of the screen.

I only noted 2 changes:
1. I switch from Note 2 to Note 4 at around the time I disposed
    the old Honda Airwave to Toyota Sienta hybrid: not sure if
    there's something in Sienta that interferes
2. Note4 tends to get very heated up while Note2 is not that
    hot while Waze is in use: I've since taken out the backcover
    of the Note4 (& used scotch tapes to hold the battery & SIM
    card in place) when in use so that the heat dissipates
I have the following c# code(all variables are doubles)

 if (Latitude == lastLocation.Latitude && Longitude == lastLocation.Longitude)

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This just compares exact numbers, what i need to do is Compare latitude and longitude to see if in 10 meters of previous location
This code runs 100 times a second, so i need it to be super fast too

I'm not sure how to achieve this so would appreciate some code help
Hiding labels on Google Maps / Street View

There is a label in exactly the wrong place and I need to hide it.


Plotting Photos on a Map

I have pictures from an iPhone6, iPhone 7 and a Canon PowerShot.

I know the iPhone 7 photos have the geo coding embedded. But I need to verify the Canon Power Shot is working for geo coding.

And if not, I may buy a new camera for myself.

And how do I view a folder of image and plot them all on a map?

Need Free Satellite Photos of New York City

I found Google Earth displays perfectly the images I need to use. But if I used that image in a presentation, I could be sued by Google.

So, I would never do that, clearly.

Are there other ways to get Satellite Photos of New York City which are public domain? Or that have some easy to accept license such as putting a copyright notice at the bottom?

I heard some French company had some which were free?

Can you please give me any Satellite Photos websites I can check their terms??

There a lots of gps apps, but usually they are more for cars & vehicles.  We are looking for one that can we can find each other within a mall or a department store.  Any EE knows of any good ones?
I wanna buy a tablets for sales staff at the company to use Citrix Apps and also to track their track.

1- What are the best brands with best price.
2- These tablets must be easy to monitoring by auditing account staff.
3- Is there a mobile printer that can be connected to the tablets and what are the best types?


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