how i can solve error Undefined function or variable 'thingSpeakRead' in matlab 2015a

writeChId = 123;              % Replace with your channel number
writeKey = 'XXX';  % Replace with your channel write key
[temp,time] = thingSpeakRead(readChId,'Fields',4,'NumPoints',20);
humidity = thingSpeakRead(readChId,'Fields',3,'NumPoints',20);
tempC = (5/9)*(temp-32); 
b = 17.62;
c = 243.5;
gamma = log(humidity/100) + b*tempC./(c+tempC);
dewPoint = c*gamma./(b-gamma)
dewPointF = (dewPoint*1.8) + 32;
thingSpeakWrite(writeChId,[temp,humidity,dewPointF],'Fields',[1,2,3],...
'TimeStamps',time,'Writekey',writeKey);

Answer 1

[Walter Roberson]

thingSpeakRead was introduced in R2019a.

In your release, there were Simulink blocks available for Arduino and Raspberry Pi to write for ThingSpeak.

To read for thingspeak in your release, you would use webread(), or perhaps webwrite() . See the https://www.mathworks.com/help/releases/R2015a/matlab/ref/webwrite.html webwrite() documentation for your release for an example of writing for thingspeak.