Get Highest high and lowest low in every last Moving Average Cross like ZigZag

Question

I am trying to code an indicator that plots the highest high and lowest low between each moving average crosses. Like a ZigZag indicator.

For example if the fast MA crosses the slow MA from below, the indicator should be looking for the highest high only and there should be only one value between the crosses. The same for a cross from above, the indicator should be plotting only one value which is the lowest low since the last cross.

I am new to Pine script, but not new to coding in general. I find it challenging to code the simplest things with Pine script. I am learning how to code in this language.

Please help direct me on how to find the correct answer. Thank you

//@version=4
study(title="MA Cross", overlay=true, max_bars_back=3000)

MA1 = sma(close, 20)
MA2 = sma(close, 100)

Highest(src, len) =>
    max = high
    for i = 1 to len
        if src[i] > max
            max := src[i]
    max

Lowest(src, len) =>
    min = src[0]
    for i = 1 to len
        if src[i] < min
            min := src[i]
    min

HH = 0.0
HH := Highest(high, barssince(cross(MA1, MA2)))

LL = 0.0
LL := Lowest(low, barssince(cross(MA1, MA2)))

HighLow = 0.0

if(MA1 > MA2)
    HighLow := HH
else
    if(MA1 < MA2)
        HighLow := LL
    else
        HighLow := na


plot(series=HighLow, color = color.red, linewidth=3)
plot(series=MA1, color = color.aqua, linewidth=1)
plot(series=MA2, color = color.orange, linewidth=1)

Answer 1

I'm not 100% sure but, the problem seems to be related to the fact that barssince() returns series[integer] and when you use that in for condition, it causes problems.

So, you need to implement your own barssince() . I used a simple counter for that.

//@version=4
study(title="MA Cross Debug", overlay=false, max_bars_back=3000)

MA1 = sma(close, 20)
MA2 = sma(close, 100)

var cntA1LessThanA2 = 0
HighestCross = 0.0

MovingAverage_Long  = crossover(MA1, MA2) 

Highest(src, len) =>
    max = high
    for i = 1 to len
        if (src[i] > max)
            max := src[i]
    max

if (MA1 > MA2)
    cntA1LessThanA2 := cntA1LessThanA2 + 1
else
    cntA1LessThanA2 := 0

if (MA1 > MA2)
    HighestCross := Highest(high, cntA1LessThanA2)

else
    HighestCross := na

plot(series=barssince(MA1<MA2), title="barssince", color=color.green, linewidth=3)
plot(series=cntA1LessThanA2, title="cntA1LessThanA2", color=color.red, linewidth=3)

In the indicator below in the screenshot, I plot the counter (red) and return value of barssince() (green), to show you counter works as expected.

plot(series=barssince(MA1<MA2), title="barssince", color=color.green, linewidth=3)
plot(series=cntA1LessThanA2, title="cntA1LessThanA2", color=color.red, linewidth=3)

Note that, your indicator will not have a valid output if MA >= M1 because you are asigning na to HighestCross in that case. But I guess you already know that.

if (MA1 > MA2)
    HighestCross := Highest(high, cntA1LessThanA2)

else
    HighestCross := na

plot(HighestCross, color = color.red, linewidth = 3)

I believe you can take it from here.