n/a 当 line.new 在 Pine Script TradingView 中使用 if 语句时的值

Question

我想创建一个指标，显示收盘价何时越过趋势线。

这是代码，这里的“trendLineCrossover”应该在交叉条上显示 1.00，在其他条上显示 0.00。但实际上这只在最后一个柱（和连续区域）上显示 0.00，在其他柱上它显示 n/a .

lineObj = if (syminfo.tickerid == "BINANCE:SRMUSDT")
    if (barstate.islast)
        line.new(x1=3380-89, y1=0.9609, x2=3380 , y2=1.0216)

line.set_extend(id=lineObj, extend=extend.right)
trendLine = line.get_price(lineObj, 0)

trendLineCrossover = crossover(close, trendLine)
plotshape(trendLineCrossover, title="trendLineCrossover", color=color.purple, style=shape.xcross)

如何修改代码以显示预期结果？谢谢

Answer 1

在这里，我们在 x2 柱号 3380 上绘制您的线，并在每个柱上评估的条件中包含 barstate.islast，因为将您的线图调用包含在 if 块内不会使交叉检测成为可能：

版本 1

//@version=4
study("", "", true, max_bars_back = 5000)
var line lineObj = na
trendLineCrossover = false
if (syminfo.tickerid == "BINANCE:SRMUSDT") and bar_index == 3380
    lineObj := line.new(x1=bar_index-89, y1=0.9609, x2=bar_index , y2=1.0216, extend=extend.right)
        
trendLine = line.get_price(lineObj, bar_index)
trendLineCrossover := barstate.islast and crossover(close, trendLine)
plotshape(trendLineCrossover, title="trendLineCrossover", color=color.purple, style=shape.xcross)

// For validation only.
c = close < trendLine
plotchar(c, "c", "•", location.top, size = size.tiny)

// Show bg starting at the bar where we draw our line.
bgcolor(bar_index > 3380-89 ? color.silver : na)

版本 2

//@version=4
study("", "", true)
var line lineObj = na
if (syminfo.tickerid == "BINANCE:SRMUSDT") and bar_index == 3380
    lineObj := line.new(x1=bar_index-89, y1=0.9609, x2=bar_index , y2=1.0216, extend=extend.right)
        
trendLine = line.get_price(lineObj, bar_index)
trendLineCrossover = crossover(close, trendLine)
plotshape(trendLineCrossover, title="trendLineCrossover", color=color.purple, style=shape.xcross)

// —————— For validation only.
// Bar no.
plotchar(bar_index, "bar_index", "", location.top, size = size.tiny)
// Plots the value returned by line.get_price() so you can see when it becomes available.
plot(trendLine, "trendLine", color.blue, 6, transp = 60)
// Show bg starting at the bar where where the line is drawn.
bgcolor(bar_index > 3380 ? color.silver : na)

n/a 当 line.new 在 Pine Script TradingView 中使用 if 语句时的值

n/a value when line.new with if statement in Pine Script TradingView

algorithmic-trading

pine-script

版本 1

版本 2