7

Well, kinda depends on your programming-language of choice, but i've developed mineturer.org in Java (the site is essentially a site for uploading, analyzing and displaying GPX-data). Iv'e used JAX-B (http://jaxb.java.net/) to read GPX files (based on the GPX schema) and JTS (http://www.vividsolutions.com/jts/) + own code for analyzing. The source code ...


6

I am not familiar with Strava, but in QGIS you can use a combination of blending modes and draw effects to get a raster-like feel, similar to the image above. You can find both of them in the Style Properties of your layer (blending modes are under Layer Rendering).


6

Sounds like a use case for Trajectools - Day trajectories from point layer. It creates lines from timestamped points, e.g. here is an example of three days of ship movement: Computing the length per line can then be done as described by Gabriel. While the tool should be easy to use, the installation is a bit involved on Windows since the plugin requires ...


5

The comments below your question bring up some good points, especially about interpreting satellite data quality (# of satellites, signal strength), and you could use this information either on the mobile device or on the server to filter out "bad" GPS values. The question comes down to two parts: 1) how do you define a spurious GPS reading, and 2) how do ...


4

Personally I store data collected by my GPS unit as a point layer with a time stamp field, then I can use ST_Makeline if I need the line strings. If you have Postgres 9.0+ you can use an ORDER BY in your aggregate calls to make sure the line goes from point to point in chronological order. I lose the M values along the created lines, but if I need them I ...


4

First, you need a field populated with the day, to later group the waypoints by day. In your case, you can create a new string type field and populate it in the field calculator with the expression: substr( "name", 6, 7) It will extract a substring of the "name" field, starting in the 6th character, and with a length of 7 characters (i.e., 21APR16). ...


3

Images of data are a bit hard to read in... But... If you read it into R as a data frame then you can group it by ID and sort it by Date and that gives you the points of the track, which can then be plotted or have the distance and speed calculated... ...but you might want to investigate some of the R packages for animal tracking that are designed for this ...


3

I wrote a math C#-lib for 2d/3d math targeting GPS handling: reading GPX & TCX, filtering & simplification of tracks, clustering tracks / segments and transforming to 2d plane. https://www.nuget.org/packages/Math.Matthey/ https://www.nuget.org/packages/Math.Matthey.Tools.TrackReaders/


3

I think Hausdorff distance may be what your looking for. It's basically a measure of how similar two geometries are. General steps to apply it to this problem: Find the closest point on the track to beginning and end of each planned segment. divide the track into segments between these sets of points. Calculate the Hausdorff distance between the planned ...


3

I can imagine a solution using a SpatiaLite database provided each trackpoint has some sequential id number. First import your CSV file into spatialite (plenty of sources available to explain this step) then make it a spatial layer: (I assume the CSV has columns longitude, latitude for the GPS locations, and a column 'id' with the sequential numbering of the ...


2

I am the developer of qgis flowmapper plugin. I would be please to answer any questions regarding the plugin. A readme and tutorial data is already included within the zip file that you have downloaded either from the plugin repo or from the website www.cempro.tk Briefly, supply (i) input node coordinates as text file and (ii) flow data matrix as text file ...


2

I haven't used it myself so far, but i think that the Flow Mapper Plugin would be the way to go. If you can't find the plugin, try checking "show all plugins, even those marked as experimental" under the Plugins -> Fetch python plugins -> Tab:Options To get additional info on the plugin, browse to your .qgis folder within your users folder. .qgis/python/...


2

It depends on what you will want to do with the data once they are loaded in the database. If each data point has associated attributes in addition to time (e.g., engine temperature reading, a photo) or of you will want to use the point data in an analysis, then storing each datum in its own row is a good choice. If each track has associated attributes (e.g....


2

The GPS Toolkit should help. It's an open source library and suite of applications that aims to free researchers from lower level coding. It provides the following functionality: RINEX utilities Positioning Residual analysis Ionospheric modeling Signal Tracking Simulation T Basic transformations Observation data collection and conversion File comparison ...


2

Hope Expert GPS will help you. Use the Simplify command to smooth out a tracklog that suffered from poor GPS reception.


2

You can to use the number of sats used to take the last fix, not the ones in view. Eg. View = 11, Fix = 5 And use the Max DB values of the signal of the strongest sat. This has to be over 30Db to get a decent signal. The devices we use have a concept of moving/non moving, sensors are : Acceleration, vibration, input voltage, input signal (from key ...


2

We've managed to tweak the motion sensor data. Using the motion sensor data, ignition data, and speed reported by the GPS tracker we should be able to tell when a vehicle is moving or not with pretty good accuracy. Also we've taken a look at the number of satellites, and that didn't look to well. While the number of satellites was lower for a vehicle under ...


2

I would suggest to set a tolerance around the position of the the points (roughly 10 m) then your merge the position when the distance is below the tolerance. Similarly, you can run a kernel along your track to find out the average position. The tricky part is to also account for time in order to avoid merging two parallel tracks. another solution is to ...


2

From the above example, I suggest that you Create points along the green lines at a regular interval Get the perpendicular distance from those points to the blue line and, finally, Compute the average error based on those distances. Note that you could reject points that are too far (above a given tolerance for GPS worst precision) due to the absence of ...


2

I made a simmilar application a few time ago. I registered my cellphone position, sending a CSV each 5 minutes, and inserting it in a postGIS database. To sum up: Load csv in PostGIS database. I made it with shell script in the server, run each 5 minutes, and update the table. Filter the results on the database. Once in postgis, you can export it to a kml/...


2

Here's a workflow to plot the lines from points, excluding the parts where the gap is > 5000m Points to Path algorithm, order by time and group by MMSI, results in 'paths' Explode lines algorithm on 'paths', results in 'exploded'. (now the lines are split into individual segments) Select by expression on 'exploded' with expression $length > 5000 . Toggle ...


2

You can use points to path using timestamp to group points. This should create lines between points with identical timestamp atttibute then use field calculator to get line distances. In case timestampes are not exactly identical, use field calculator to round times as much as necessary.


2

this is how looks like my strava routes, rendered in QGIS. What I do is to merge all gpx tracks (otherwise you should change blending mode one by one) into a single file and then, into the Layer Properties > Symbology tab, choose an appropriate colour, then opening the layer rendering options to select Screen as the blending type for the Features parameter ...


1

The following workflow is for QGIS and will give you the mean distance from the route for each transect in metres. I'm assuming the data will be using a projection in metres. Buffer your transects and route, for example, by 1m with Vector > Geoprocessing Tools > Buffer(s). You now have two polygon layers - the transects and the route. Give the route ...


1

The way to do this is to turn your tracklog into a line, this might help. Then you can detect self-intersections in the line using topology. The logic for this is for there to be a loop the line must cross itself at some point. Links are for QGIS, which I assume you are using to view your PostGIS data; if you're not it doesn't cost much (it's free) and does ...


1

I am no expert in this field, just thinking out aloud. You could try to break your track up into individual points. Filter out points say above 1mph this leaves a bunch of either non moving or very slowly moving points. Then run some point density tool, this should create a grid where points are most dense which would be your meeting places? This assumes ...


1

The Trajectools plugin for QGIS provides a tool to create trajectories from points: Using geometry generators, the resulting LinestringM features can be styled according to the local speed:


1

There is a open source lib I just finished developing (to stable) and UI for analyzing GPX, TCX and fit files. The lib is https://github.com/jimmykane/quantified-self-lib The UI based on Angular https://github.com/jimmykane/quantified-self Live Demo https://www.quantified-self.io What it can do is parse a GPX,TCX or Fit file, generate stats such as ...


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