找股价在ma21以上

//version=5
indicator("Scan: MA5>MA250 & Price<MA21", overlay=false)

ma5 = ta.sma(close, 5)
ma21 = ta.sma(close, 21)
ma250= ta.sma(close, 250)

ma250_up = ma250 > ma250[20] // 长期上升过滤
vol_ok = volume >= ta.sma(volume,20)*0.5 // 流动性过滤（可选）

signal = (ma5 > ma250) and (close < ma21) and ma250_up and vol_ok

plot(signal ? 1 : 0, style=plot.style_columns, title="Signal")
hline(0, color=color.gray)
hline(1, color=color.green)