I’m trying to write any derived variable in Ubidots for Education. Currently I have
voltage variable which correctly getting updated values every 30sec. Now want to create simple derived variable:
hour_voltage_diff = max(voltage, “1H”) - min(voltage, “1H”)
After adding formula max - min, there is totally no data in my derived variable. It’s not important how long I would wait. I can’t use any aggregation function and even shift is not working. Please help me.