Mastering Internet of Things

Removing random spikes

We now have a value that is 10 times more accurate than the original, in cases where our ambient light is not expected to vary quickly. This is typically the case, if ambient light depends on the sun and weather. Calculating the average over a short window has an added advantage: it allows us to remove bad measurements, or spikes. When a physical quantity changes, it normally changes continuously, slowly, and smoothly. This will have the effect that roughly half of the measurements, even when the input value changes, will be on one side of the average value, and the other half on the other side. A single spike, on the other hand, especially in the middle of the window, if sufficiently large, will stand out alone on ...