GPS is a space-based satellite navigation system that provides location and time information.

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2
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127 views

Finding intermediate points and speed over a segment

I have a dataset which is in the form of ( Time , Car ID, Speed at that moment, Lat,Long) and I need to do some machine learning on the data to answer the following questions : Best route from ...
1
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1answer
324 views

find euclidean distance in GPS [duplicate]

i need to find the distance between two gps location, So i think to do this: lat1(seconds)-lat2(seconds)=lat * 30.7151 == distance latitude in meters =Latm long1(seconds)-long2(seconds)=long ...
12
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3answers
5k views

Post Processing GPS Data with open source software

I am using Magellan Professional Mapper CX working on ArcPad 7.1 platform. It has sub-meter accuracy after post processing. Without post processing the data collected in the field is off by 10 to 15 ...
0
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2answers
180 views

I can not download gpx from GPS through GPS tool with GPS babel on QGIS

I have already install GPS tool plug-in and GPS Babel. Garmin GPS map 62s is connected my PC through USB cable. I changed device setting according to below site. ...
6
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1answer
255 views

Simulate (Mock) GPS Tracks

I have the following scenario: 1) I need to create GPX files for use in testing of a mobile device. 2) The tracks to be described within will span large distances over long time periods (i.e. it's ...
0
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1answer
86 views

Imported GPS data does not overlap with map

I´m working on QGIS and I geocoded 2 addresses of a city in Germany and tried to input the text-file as a layer. It worked, but the 2 points must be in the map of the city and if I zoom to the ...
3
votes
3answers
141 views

How long for surveying quality GPS to get accurate 3D position information

I recently read an Ordnance Survey Blog article that seemed to suggest that it was necessary to leave the GPS device in use for four hours to gather requisite data. I am aware that "domestic" GPS ...
3
votes
1answer
423 views

Is machine learning used much in GIS?

I'm new to GIS. Is machine learning used much in this field, and where? I'm investigating a job opportunity with a mapping company working on traffic awareness. My background is in supervised machine ...
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0answers
132 views

Download/Upload GPS/Qgis don't work anymore

We were using Qgis and GpsBabel to download waypoints and tracks from GPS garmin 60 or 76. Since few weeks, this is not working anymore. There is a error windows, and nothing is created. I tried ...
0
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1answer
2k views

How can I manipulate the timestamps in a GPX file?

I have a GPS tracked stored in a GPX file. Now I'm looking for a tool that allows me to set the start time of the track and the duration, and the tool should automatically evenly distribute the ...
6
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3answers
2k views

Garmin etrex raster maps support

I currently use an excellent set of printed topographic route maps for mountain biking. I would like to scan the maps, georeference them, and upload the maps to a handheld GPS device. Does the etrex ...
2
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0answers
299 views

calculating bounding box from known centre coordinate and zoom

I have a map, the centre of that map (centrepoint) is = -37,175 ( gps) I know the zoom of the map = 13 I know the size = 320x320px I know there is 111111m in a degree of latitude and a varying degree ...
1
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0answers
39 views

Twitter live feed on ArcGIS desktop [duplicate]

I am a complete beginner with ArcGIS and i have been looking for a way to live feed tweets to ArcGIS desktop. A quick google search brings this blogpost up from 2009: ...
5
votes
2answers
791 views

Storing GPS tracks with timestamps in PostGIS

I need to store a series of GPS points with timestamps in the database (traces of various vehicles). I am wondering which of two approaches to choose for storing them in the PostGIS table: 1.) Each ...
8
votes
4answers
1k views

How to build a geographic database of GPS logs?

On our aerial wildlife surveys we typically generate dozens of GPX files, and usually convert most of them into shapefiles for display in a GIS application. GPX files are a terrific way of keeping all ...
1
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2answers
133 views

QGIS Holux gpx file doesn´t show up

I´ve got a problem with displaying the imported gpx file. The gpx file is created in Holux Funtrek 130 PRo. The map I use is from Openstreetmap, I am sure it is the right map from the location I ...
0
votes
1answer
284 views

Looking for a tutorial on syncing QGIS with Trimble ProXT

Does anyone have any experience/advice to sync a TrimbleProXT gps antenna with the current "Lisboa" 1.8.0v? Additionally did you manage to collect features (points,line,polygons) in the field ok? ...
2
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0answers
85 views

How can a GPS receiver know the estimated error?

I would like to plot a circle of possible error on the map in a GPS app. From http://en.wikipedia.org/wiki/Dilution_of_precision_(GPS), we can see that GDOP is equal to "delta of output location" ...
4
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1answer
144 views

GPS Elephant Tracking II: Is ArcGIS basemap imagery orthorectified?

-- For my original question and pictures of elephants wearing GPS equipped anklets, go here. -- I'm experimenting with the use of GPS anklets to track the movement of zoo elephants. This has proved ...
10
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1answer
514 views

Overview of GPS tracking system technologies

Background: I've been asked by a friend to estimate the cost of setting up a GPS tracking system for a small fleet of buses, so we can do real time reporting of bus locations via a webmap. In my ...
3
votes
2answers
224 views

Several questions about using spatial data?

If you have spatial data for SQL server, can you use the spatial data (both geometry and geography) in another application for instance ESRI ArcGIS? Is spatial data a standard that every GIS ...
12
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4answers
4k views

Clustering Trajectories (GPS data of (x,y) points) and Mining the data

I've got 2 questions on analyzing a GPS dataset. 1) Extracting trajectories I have a huge database of recorded GPS coordinates of the form (latitude, longitude, date-time). According to date-time ...
0
votes
1answer
56 views

Is it possible to download GPX another coordinate system except WGS(GCS) with GPS Tool on QGIS1.8.0?

I got GPS data with using bessel1841 as coordinate system. When I download GPX data on GPS tool, it is automatically treated as WGS84. Can I use another coordinate system when I download GPX on GPS ...
2
votes
1answer
542 views

Where can I find Foursquare Datasets?

I'm doing research which aims to analyse location based social networks. So the Foursquare dataset is suitable for me. Is there any Foursquare dataset available? I need 4 information in the dataset: ...
14
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3answers
11k views

What is the maximum Theoretical accuracy of GPS?

I was talking with a potential client, and they requested that we plot some points with GPS, with a maximum (or should that be minimum?) accuracy of 2 m. This is an area with no WAAS, and I was under ...
5
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3answers
122 views

Can I access Trimble logged positions in ArcMap10?

We recently walked a fence perimeter with a Trimble Ranger, auto-logging positions at 5 second intervals in a generic point file. The exported file acknowledges over 800 points, but only displays the ...
0
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1answer
93 views

Alternate option for a Data Player plugin for GPS in qgis

I found a plugin for QGIS to play a GPS Track. (Data player plugin).The Problem is I can not read .gpx File with this plugin. Is there another option?
4
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3answers
429 views

Wildlife surveys using tablet and GPS, import/export to/from ArcMap

I've found some info about this on a previous post (Advanced android app for mapping and GPS logging), but it didn't provide enough info, I'm hoping some other tech experts can help! I have a tablet ...
2
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0answers
104 views

Interpolate current Course value of GPS using previous Course values

I have a set of GPS data with Lat, lon and Course. I need to interpolate current value of course, using previous values of Course. The formula I am using is not accurate in curves.In C language I was ...
4
votes
1answer
463 views

How to show a geoTiff on an iOS application?

I'm developing an iOS application that will use offline maps. These maps are on GeoTiff format but I don't know how to do it. I've found this question: How to display a GeoTIFF on mapView but it uses ...
8
votes
1answer
447 views

real time map matching

I am working on a project which requires real time map matching. I am currently using ArcGIS but not sure whether it will work. Here is what happens with my system: the cell phones sent GPS fixes ...
0
votes
1answer
679 views

How to fix the QGIS for Android GPS panel?

I have installed qgis on my samsung galaxy s1. But I cant test the gps. I found how to turn the gps on, but I cannot open the gps pannel to do it. When i press view->panels there is nothing happens.
2
votes
1answer
169 views

Keyboard shortcut for GPS data capture in QGIS

I would like to setup keyboard shortcuts for GPS data capture with QGIS. Using GPS Information dialog box, I could use Mouse-Left-Click to "Add feature" and "Add track point", but I would like to ...
19
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3answers
23k views

What are the major differences between GPS, GLONASS and Galileo?

What are the major differences between GPS, GLONASS, COMPASS and Galileo?
3
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1answer
230 views

Join GPS points obtained from .GPX file in Python Console

Having loaded the .gpx file into a new layer from python console, I'm unable to access the gps points in the attributes table. Essentially, i'm unable to join these points to form a polygon ...
7
votes
1answer
162 views

Unable to load .gpx file from Python Console

I'm trying to create a plugin which will extract the gpx files and load them onto the active layer window in QGIS. While I'm able to load it using the QGIS GUI from Layer>New Vector Layer, I'm not ...
5
votes
1answer
326 views

Why are points collected with a Trimble FM 750 off by more than a mile when displayed in QGIS?

I have a grower that has a FM 750 and is trying to make points in a field. When finished he takes the file out of the display and goes to his computer and he can bring up the points in the right ...
4
votes
2answers
334 views

Tracking a vehicle without GPS device

We are planning to write an application which have to track the user driving in his truck in the cities like New York city accurate upto which lane he was driving on. In the cities with those tall ...
1
vote
2answers
695 views

Exporting shp into a GPS [duplicate]

Possible Duplicate: How to convert .shp into .gpx using QGIS? I'm trying to convert a shapefile with some random points into a gpx file, but I'm having some problems: when I upload the gpx ...
5
votes
2answers
2k views

How to merge multiple file geodatabases into one file geodatabase?

I have created a file geodatabase that has several feature data sets, feature classes, and domains. I have created a map with the file geodatabase added to it, converted the map to ARCPAD AXF format ...
2
votes
2answers
544 views

How to convert Garmin Waypoints to Google Mercator?

I have georef some topocards with QGIS and the Google Hybrid Layer. So, this cards are connected with the Google Mercator System. Now I have some waypoints taken with Garmin GPSmap62 (in WGS84). ...
11
votes
1answer
401 views

Why does GPS altitude jump sometimes?

I am currently developing a little application in Android which uses GPS. When i click a button i start to record a "track". If i walk around i save my position every second into a file. This works ...
3
votes
0answers
180 views

QGIS: GPS Tracking with improved Altitude

I am preparing for archeological fieldwork in Sudan. I recently came up with RTK equipment and software using RTKlib to export the real time corrected data (cm level) to QGIS via a simulated NMEA ...
2
votes
0answers
390 views

How to read a .GPB file in C#?

I have a .GPB file, I need to extract the common GPS data from it but I don't find a clear structure that specify the contents of that file. as a sample record from file 00000260 02 11 A9 61 E7 96 ...
2
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0answers
189 views

How would I modify GPS tracker to accept two nmea inputs and gpsmarker to include a heading vector?

I use QGIS on a research vessel and wonder whether I could modify the QGIS 1.8.0 gpsinformation widget. I want to achieve two things. 1. Change the GPS marker to a boat shape which points in the ...
2
votes
2answers
759 views

How to find the Shortest Path between two coordinates points using pgrouting A-Star?

In PostGIS I have two tables: an osm road network and a table that contains the start and end coordinate points of each path (i.e. userid, start_x1, start_y1, end_x2, end_y2). I would like to know: 1) ...
6
votes
1answer
153 views

GIS Server for web service

I am building an app that has some GIS requirements that go a little beyond (I think) what I can retrieve from existing online web services resources so I am attempting to build a server of my own to ...
1
vote
1answer
624 views

GPS data validation

I was wondering if Fix quality data from GPGGA, can be substituted to Validity field in GPRMC? In my application I have to use only GPRMC, but I don't really know if it sets validity only if Fix ...
2
votes
1answer
107 views

Pathfinder Differential Correction: “Use reference position from” who?

How do you choose either "base files" or "base provider"?
2
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0answers
120 views

How to configure various client applications to display AVL data?

Given x number of GPS units transmitting NMEA formatted strings back to a server (xxx.xxx.xxx.xxx:xxxxx) is there a way to listen in on the traffic and parse NMEA formatted strings for display on a ...