If I want to compare the close of today with the high of the last 4 days, what is the format? I have used
_hi = close > high[4] ? 1 : 0
But that only counts the high 4 days ago, not the days in between. I have tried
_hi = close > high[1,2,3,4] ? 1 : 0
Error message
You can use highest() for that purpose.
highest(source, length) → series
You need to be careful though. close > highest(close, 4) can never be true. Because, if the current bar's close price is the highest among those 4 bars, highest() will return current bar's close price. Therefore, that check would be close > close, which can never be true.
You can either do close > highest(nz(close[1]), 4) or close == highest(close, 5) (It is 5, because current bar is also included. But you want to compare the previous 4 bars).
Have a look at the following code and chart. One is using close > highest(nz(close[1]), 4) and the other one is using close == highest(close, 5). As you can see, the output is identical.
//@version=3
study(title="Compare 2", overlay=true)
_hi = close > highest(nz(close[1]), 4)
plotshape(series=_hi, title="_hi", text="hi", style=shape.triangleup, location=location.belowbar, color=color.green, size=size.small, transp=40)
