How should I present multiple point on the map in ThingSpeak Visualization code?

I am working on showing the coordinate on the map in my ThingSpeak channel. However, it only allow to show 1 coordinate on my created map. How should I hold the previous coordinate, then adding multiple coordinate continuously without refreshing the webpage? (Paid license account)

Hopefully someone can provide your suggestion to me. Thanks in advance.

Answer 1

[Christopher Stapels]

I recommend writing the position data to your channel feed in the latitude and longitude fields.

https://api.thingspeak.com/update.json?api_key=xxxxxxxxxxxxxxxx&lat=22.3&long=34.5

Then in your MATLAB visualization, use thingSpeakRead, and set the name-value pair 'location' to true.

myData=thingSpeakRead(876466,'Location',true,'outputformat','timetable','numPoints',10);

now you can use geoscatter or any of the other great mapping functions to plot your data.

geoscatter(myData.Latitude,myData.Longitude)

[Candy Lau]

Perfect solution! Thank you so much!

Answer 2

[Fabio Battagion]

Chris,

if I set the LAT and LON values in the Channel Setting (from the channel definition interface), I see that the location information (lat & lon) are not available for geoscatter() function. So, i should write all the time, in addition to the fileds loaded in the channel, also the LAT & LON values. Is it true?

Thanks

Fabio

[Christopher Stapels]

LAT and LON values in the Channel Setting are for the channel location which is intended to be static. In the data feed, lattitue and longitude are for the device location. You can set the device location using the write data api or with thingSpeakWrite. The channel location is like the base station, and the device location is intended to be where the measurements are coming from.

That said, you can read the channel information with the Read Settings API, but I would not use this for your use case. Be careful if you do use that one, it needs the user API, not the channel API (for the above you use the channel API).