ThingSpeak

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good morning!, I'm learning in MatlLab and ThingSpeak, and I'm a bit lost ... I have a variable that changes state from 0 to 1. And I want to know how I can calculate the times it changes state, and the time that remains for Example in state 1. Can you help me? Thank you so much

When I try to plot temperature data over time the displayed time is two hours behind. When I try to change timezones in the following manner results are very erratic: [data, time] = thingSpeakRead(readChannelID, 'Field', fieldID1, 'NumPoints', 64, 'ReadKey', readAPIKey); %% Visualize Data %% time.TimeZone = 'Europe/Brussels' plot(time, data,'- . r'); Most timezones from this list don't change the time at all, using using some I get say one hour closer but never the right amount. What am I doing wrong? How come only a few timezones from the list even have any effect? Keep in mind I am a n00b. For the record I am using the in browser editor on thingspeak.com, running a MATLAB visualisation plotting my cloud data.

Hello. I am trying to read online sensor data using the ThingSpeak API. I format my url in the following way: https://api.thingspeak.com/channels/{}/feeds.csv?api_key={}&average=60&offset=0&round=2&start=2021-04-01 00:00:00&end=2021-07-31 00:00:00 Where the two '{}' are replaced with the channel ID and read Key respectively. The problem is that the data returned only spans about 10 days which is only a fraction of what the url specified. Is there a way to avoid this limit and retrieve all the data requested in a single call, or do multiple API calls have to be made if the timeframe I need is greater than 10 days? Thank you in advance!

I have a CSV generated from ThingSpeak, which contains a datetime containing a time zone identifier (CEST in my case). It looks like this: created_at,entry_id,field1,field2,field3,latitude,longitude,elevation,status 2020-06-06 18:36:17 CEST,1,434,2.12121212121,30.3487192708,,,, 2020-06-06 18:36:33 CEST,2,433,2.11632453568,30.2823285934,,,, 2020-06-06 18:36:48 CEST,3,436,2.13098729228,30.4815006257,,,, 2020-06-06 18:37:03 CEST,4,433,2.11632453568,30.2823285934,,,, Now, when I edit the file and remove " CEST" from all rows, readtimetable imports the file properly, with no issues. But when I leave it as is, readtable imports the field as text, while readtimetable refuses altogether. I tried to specify the format manually, as so: opts.VariableNames = ["created_at", "Var2", "field1", "Var4", "Var5", "Var6", "Var7", "Var8", "Var9"]; opts.SelectedVariableNames = ["created_at", "field1"]; opts.VariableTypes = ["datetime", "string", "double", "string", "string", "string", "string", "string", "string"]; opts = setvaropts(opts, "created_at", "InputFormat", "dd-MM-yyyy HH:mm:ss z", "TimeZone", 'Europe/Warsaw'); With this, readtimetable works but... all fields are turned into NaT. Now, this is some weird behavior, because using the datetime function with one of those fields copied works flawlessly: >> date = datetime("2020-06-06 18:36:17 CEST","InputFormat","yyyy-MM-dd HH:mm:ss z","TimeZone","Europe/Warsaw") date = datetime 06-Jun-2020 18:36:17 Matlab's importer also can't handle it, when I use the CSV file as the input it wrongly detects the delimiter, once that's corrected and field type set to datetime, any way I tried configuring the input format just fails and results in NaTs. I even attempted to set the format to "yyyy-MM-dd HH:mm:ss 'CEST'", so the time zone gets treated as a string, but it still fails to recognize it as a correct datetime. Using Matlab R2020a

Hello! How do I pick up a data in the specific time period through all the days back? This is my code so far... % set time range from 8H to 12H of every day S = timerange('08:00:00','12:00:00'); % Read Temperature Data data = thingSpeakRead(readChannelID,'Fields',TemperatureFieldID, ... 'timerange',S, 'ReadKey',readAPIKey); % Calculate the maximum and minimum temperatures in the period [maxTempF] = max(data); [minTempF] = min(data); I would be so happy for any ideas :)