I have a magnetometer, a LIS3MDL to be precise, and I am taking readings from it every second. As expected there is variation in the readings. For example, if I take five readings I get:
1164, 1190, 1270, 1186, 1260
Now maybe five samples is enough to average over, maybe it is not. How do I know this? Is there a way to use the FFT of a large number of samples to work out the optimum number of samples to take?