Arduino Exponential-Filter provides an exponential filter to smooth a "noisy" input data value.
OUTPUT[t] = OUTPUT[t-1] + α(INPUT[t] - OUTPUT[t-1])
+= α(INPUT[t] - OUTPUT[t-1])
Where:
α = ∆t/ (RC + ∆t)
When:
τ = RC [seconds]
= 1 / 2πƒ