Pine code v5, the rank and the abs functions not recognised

Question

this pinescript v5 doesn't seem to work for me, do you see anything wrong, how to correct it?

//@version=5
indicator("Top 20 Candles with Highest Absolute Differences", overlay=true)

// calculate the absolute difference between open and close prices using math.abs() function
abs_diff = math.abs(open - close)

// get the top 20 candles with the highest absolute differences over the last 200 days
rank = rank(abs_diff, 200)
is_top_20 = rank <= 20

// color the top 20 candles black
bar.color(is_top_20 ? color.black : na)

My tradingview account doesn't recognise the 'Rank' and the 'Abs' functions in the way I wrote them.

Answer 1

Please check the script below:

//@version=5 
indicator("Top 20 Candles with Highest Absolute Differences", overlay=true)

lookback = input.int(200, "Lookback window, bars")

// calculate the absolute difference between open and close prices using math.abs() function 
abs_diff = math.abs(open - close)

var diffs = array.new<float>()
diffs.unshift(abs_diff)
while diffs.size() > lookback // keep array size <= 200
    diffs.pop()



// get the top 20 candles with the highest absolute differences over the last 200 days 
// rank = rank(abs_diff, 200) 
// is_top_20 = rank <= 20
rank = diffs.percentrank(0)
is_top_20 = rank >= 80

lb = label.new(bar_index, high, str.format("{0,number, 0}", rank), style = label.style_none, size = size.normal, textcolor = color.yellow)
lb1 = label.new(bar_index, low, str.format("{0,number, 0.0}", abs_diff), style = label.style_label_up, size = size.normal, textcolor = color.yellow)


// color the top 20 candles black 
barcolor(is_top_20 ? color.black : na)
bgcolor(is_top_20 ? color.rgb(163, 234, 236, 51) : na)