// Input options
maLen = input(title="SMA Length", type=input.integer, defval=20)
stdLen = input(title="StdDev Length", type=input.integer, defval=20)
offset = input(title="StdDev Offset", type=input.float, defval=2.0)
// Calculate values
maValue = sma(close, maLen)
stdValue = stdev(close...