RSI-Trend

study(title="RSI-Trend", shorttitle="RSI-Trend")
src = close, len = input(200, minval=1, title="Length")
smooth = input(1, minval=0, title="Smooth")

up = rma(max(change(src), 0), len)
down = rma(-min(change(src), 0), len)
rsi = down == 0 ? 100 : up == 0 ? 0 : 100 - (100 / (1 + up / down))
rsiema=ema(rsi, smooth)

plot(rsiema, color=blue, transp=0, linewidth=2)
band1 = hline(49.5)
band0 = hline(50.5)
banmx = hline(55)
banmn = hline(45)
ban50 = hline(50)

fill(band1, band0, color=red, transp=80)