Bollinger Bands
study(shorttitle="BB", title="Bollinger Bands", overlay=true) source = close length = input(20, minval=1), mult = input(2.0, minval=0.001, maxval=50) basis = sma(source, length) dev = mult * stdev(source, length) upper = basis + dev lower = basis - dev plot(basis, color=red) p1 = plot(upper, color=blue) p2 = plot(lower, color=blue) fill(p1, p2)