how can i solve this error appears when I try reading position

Hello:

I am trying to read the position (latitude and longitde) from a data with thingSpeakRead and the next error appears:

Dot indexing is not supported for variables of this type

This is my code from MATLAB Visualizations code:

data = thingSpeakRead(1299642, 'location',true)
lon = data.Longitude;
lat = data.Latitude;
figuregeoplot(lat,lon,'red-*')
geobasemap("topographic")
title("Ground Truth Trajectory")

And this is the output:

data =
     []
Dot indexing is not supported for variables of this type.
Error in Posicion (line 3)lon = data.Longitude;

Someone knows what is happening?

Thank you

[KSSV]

Just run this line:

data = thingSpeakRead(1299642, 'location',true)

There is no data, it is empty. As the data is empty you are getting error from the next line data.. Check this line alone why the data is empty.

Answer 1

[Vinod]

Your channel is empty, and you are trying to index into an empty array retrieved from the channel. Try this:

data = thingSpeakRead(1299642, 'location',true)
if ~isempty(data)
  lon = data.Longitude;
  lat = data.Latitude;
  figuregeoplot(lat,lon,'red-*')
  geobasemap("topographic")
  title("Ground Truth Trajectory")
end