How to add more Standard Deviation to this VWAP indicator?

I would like to add two additional standard deviation levels to this indicator, but I couldn't get it to work properly. I attempted to do this by duplicating the existing standard deviation (stdv) code in the source file and modifying it accordingly. However, the output was not as expected, and the added levels did not function correctly.

https://www.tradingview.com/script/Cnk6E8IO-Koalafied-VWAP-D-W-M-Q-Y/

// This source code is subject to the terms of the Mozilla Public License 2.0 at https://mozilla.org/MPL/2.0/
// © TJ_667

// Volume Weighted Average Price for multiple periods with Standard Deviation band selection - Daily, Weekly, Monthly, Quarterly, Yearly 


indicator("Koalafied VWAP D/W/M/Q/Y ", overlay = true)

// ---------- Functions ---------- //

// TradingView vwap function. Taken out stdev calcs to put in seperate function. 
computeVWAP(src, isNewPeriod) =>
    var float sumSrcVol = na
    var float sumVol = na
    var float sumSrcSrcVol = na

    sumSrcVol := isNewPeriod ? src * volume : src * volume + sumSrcVol[1]
    sumVol := isNewPeriod ? volume : volume + sumVol[1]
    // sumSrcSrcVol calculates the dividend of the equation that is later used to calculate the standard deviation
    sumSrcSrcVol := isNewPeriod ? volume * math.pow(src, 2) : volume * math.pow(src, 2) + sumSrcSrcVol[1]

    _vwap = sumSrcVol / sumVol
    variance = sumSrcSrcVol / sumVol - math.pow(_vwap, 2)
    variance := variance < 0 ? 0 : variance
    stDev = math.sqrt(variance)

    [_vwap, stDev]

// Standard Deviation Band calculation function
compute_stDEV(_vwap, stDev, stDevMultiplier_1, stDevMultiplier_2) =>

    upperBand_2 = _vwap + stDev * stDevMultiplier_2
    upperBand_1 = _vwap + stDev * stDevMultiplier_1
    lowerBand_1 = _vwap - stDev * stDevMultiplier_1
    lowerBand_2 = _vwap - stDev * stDevMultiplier_2
    
    [upperBand_2, upperBand_1, lowerBand_1, lowerBand_2]

// Label function from sbtnc - Daily Weekly Monthly Opens script
f_drawLabel(_x, _y, _text, _textcolor, _style, _size) =>
    var _label = label.new(
     x          = _x,
     y          = _y,
     text       = _text,
     textcolor  = _textcolor,
     style      = _style,
     size       = _size,
     xloc       = xloc.bar_time
     )
    
    label.set_xy(_label, _x, _y)

// ---------- VWAP selection ---------- //

src = input(hlc3, "VWAP Source")

plot_vD = input(true, "Plot Daily VWAP")
plot_vW = input(true, "Plot Weekly VWAP")
plot_vM = input(true, "Plot Monthly VWAP")
plot_vQ = input(true, "Plot Quarterly VWAP")
plot_vY = input(true, "Plot Yearly VWAP")

showStd = input(false, "Plot Standard Deviation")
Std_selection = input.string(title = "Standard Deviation Option", defval="Day", options = ["Day", "Week", "Month", "Quarter", "Year"])

stDevMultiplier_1 = input(1.0, "StDev mult 1")
stDevMultiplier_2 = input(2.0, "StDev mult 2")

show_labels = input(true, "Show Labels")
fill_bands = input(false, "Fill Bands")

plot_pL1 = input(false, "Plot Previous Period 1+- Levels")
plot_pL2 = input(false, "Plot Previous Period 2+- Levels")

show_plabels = input(true, "Show Previous Labels")
fill_pbands = input(false, "Fill Previous Bands")

off_mult = input(15, "Label offset")
var DEFAULT_LABEL_SIZE      = size.small
var DEFAULT_LABEL_STYLE     = label.style_none
ll_offset = timenow + math.round(ta.change(time)*off_mult)

// ---------- VWAP Calculations ---------- //

timeChange(period) =>
    ta.change(time(period))

newSessionD = timeChange("D")
newSessionW = timeChange("W")
newSessionM = timeChange("M")
newSessionQ = timeChange("3M")
newSessionY = timeChange("12M")


// ---------- VWAP Function Calls ---------- //

[vD, stdevD] = computeVWAP(src, newSessionD)
[vW, stdevW] = computeVWAP(src, newSessionW)
[vM, stdevM] = computeVWAP(src, newSessionM)
[vQ, stdevQ] = computeVWAP(src, newSessionQ)
[vY, stdevY] = computeVWAP(src, newSessionY)


    
    
// ---------- Plot VWAPs ---------- //

vDplot = plot(plot_vD ? vD : na, title = "VWAP - Daily", color = color.red, style = plot.style_line, transp = 0, linewidth = 1)
f_drawLabel(ll_offset, show_labels and plot_vD ? vD : na, "--------- vD   ", color.red, DEFAULT_LABEL_STYLE, DEFAULT_LABEL_SIZE) 

vWplot = plot(plot_vW ? vW : na, title = "VWAP - Weekly", color = color.white, style = plot.style_line, transp = 0, linewidth = 1)
f_drawLabel(ll_offset, show_labels and plot_vW ? vW : na, "--------- vW   ", color.white, DEFAULT_LABEL_STYLE, DEFAULT_LABEL_SIZE) 

vMplot = plot(plot_vM ? vM : na, title = "VWAP - Monthly", color = color.blue, style = plot.style_line, transp = 0, linewidth = 1)
f_drawLabel(ll_offset, show_labels and plot_vM ? vM : na, "--------- vM   ", color.blue, DEFAULT_LABEL_STYLE, DEFAULT_LABEL_SIZE) 

vQplot = plot(plot_vQ ? vQ : na, title = "VWAP - Quarter", color = color.green, style = plot.style_line, transp = 0, linewidth = 1)
f_drawLabel(ll_offset, show_labels and plot_vQ ? vQ : na, "--------- vQ   ", color.green, DEFAULT_LABEL_STYLE, DEFAULT_LABEL_SIZE) 

vYplot = plot(plot_vY ? vY : na, title = "VWAP - Year", color = color.yellow, style = plot.style_line, transp = 0, linewidth = 1)
f_drawLabel(ll_offset, show_labels and plot_vY ? vY : na, "--------- vY   ", color.yellow, DEFAULT_LABEL_STYLE, DEFAULT_LABEL_SIZE) 


// ---------- Standard Deviation Calc ---------- //

stdev_sel = Std_selection == "Day" ? stdevD : 
         Std_selection == "Week" ? stdevW : 
         Std_selection == "Month" ? stdevM : 
         Std_selection == "Quarter" ? stdevQ : 
         Std_selection == "Year" ? stdevY : na

vwap_sel = Std_selection == "Day" ? vD : 
         Std_selection == "Week" ? vW : 
         Std_selection == "Month" ? vM : 
         Std_selection == "Quarter" ? vQ : 
         Std_selection == "Year" ? vY : na

prev_period = Std_selection == "Day" ? newSessionD : 
         Std_selection == "Week" ? newSessionW : 
         Std_selection == "Month" ? newSessionM : 
         Std_selection == "Quarter" ? newSessionQ : 
         Std_selection == "Year" ? newSessionY : na

[s2up, s1up, s1dn, s2dn] = compute_stDEV(vwap_sel, stdev_sel, stDevMultiplier_1, stDevMultiplier_2)

a = plot(showStd ? s2up : na, title = "VWAP - STDEV +2", color = color.red, style = plot.style_linebr, linewidth = 3, transp = 70)
f_drawLabel(ll_offset, show_labels and showStd ?  s2up : na , "     -------- SD+2   ", color.red, DEFAULT_LABEL_STYLE, DEFAULT_LABEL_SIZE) 

b = plot(showStd ? s1up : na, title = "VWAP - STDEV +1", color = color.gray, style = plot.style_linebr, linewidth = 3, transp = 60)
f_drawLabel(ll_offset, show_labels and showStd ?  s1up : na , "     -------- SD+1   ", color.gray, DEFAULT_LABEL_STYLE, DEFAULT_LABEL_SIZE) 

c = plot(showStd ? s1dn : na, title = "VWAP - STDEV -1", color = color.gray, style = plot.style_linebr, linewidth = 3, transp = 60)
f_drawLabel(ll_offset, show_labels and showStd ?  s1dn : na , "     -------- SD-1   ", color.gray, DEFAULT_LABEL_STYLE, DEFAULT_LABEL_SIZE) 

d = plot(showStd ? s2dn : na, title = "VWAP - STDEV -2", color = color.blue, style = plot.style_linebr, linewidth = 3, transp = 70)
f_drawLabel(ll_offset, show_labels and showStd ? s2dn : na , "     -------- SD-2   ", color.blue, DEFAULT_LABEL_STYLE, DEFAULT_LABEL_SIZE) 

fill_col_up = color.new(color.red, 95)
fill_col_mid = color.new(color.gray, 90)
fill_col_down = color.new(color.blue, 95)

fill(a, b, fill_bands ? fill_col_up : na)
fill(b, c, fill_bands ? fill_col_mid : na)
fill(c, d, fill_bands ? fill_col_down : na)


// ---------- Previous period levels ---------- //

previouslevels(period, VWAP, s2up, s1up, s1dn, s2dn) =>
    var float pV = na
    var float ps2up = na
    var float ps1up = na
    var float ps1dn = na
    var float ps2dn = na
    pV := period ? VWAP[1] : pV
    ps2up := period ? s2up[1] : ps2up
    ps1up := period ? s1up[1] : ps1up
    ps1dn := period ? s1dn[1] : ps1dn
    ps2dn := period ? s2dn[1] : ps2dn

    [ pV, ps2up, ps1up, ps1dn, ps2dn ]

[ pV, ps2up, ps1up, ps1dn, ps2dn ] = previouslevels(prev_period, vwap_sel, s2up, s1up, s1dn, s2dn)

// ---------- Plot previous levels ---------- //

pVplot = plot(plot_pL1 ? pV : na, title = "Previous VWAP", color = color.orange, style = plot.style_linebr, transp = 60, linewidth = 1)
f_drawLabel(ll_offset, show_plabels and plot_pL1 ? pV : na, "--------- pVWAP   ", color.gray, DEFAULT_LABEL_STYLE, DEFAULT_LABEL_SIZE) 

pa = plot(plot_pL2 ? ps2up : na, title = "Previous VWAP - STDEV +2", color = color.red, style = plot.style_linebr, linewidth = 1, transp = 70)
f_drawLabel(ll_offset, show_plabels and plot_pL2 ?  ps2up : na , "     -------- pSD+2   ", color.red, DEFAULT_LABEL_STYLE, DEFAULT_LABEL_SIZE) 

pb = plot(plot_pL1 ? ps1up : na, title = "Previous VWAP - STDEV +1", color = color.gray, style = plot.style_linebr, linewidth = 1, transp = 60)
f_drawLabel(ll_offset, show_plabels and plot_pL1 ?  ps1up : na , "     -------- pSD+1   ", color.gray, DEFAULT_LABEL_STYLE, DEFAULT_LABEL_SIZE) 

pc = plot(plot_pL1 ? ps1dn : na, title = "Previous VWAP - STDEV -1", color = color.gray, style = plot.style_linebr, linewidth = 1, transp = 60)
f_drawLabel(ll_offset, show_plabels and plot_pL1 ?  ps1dn : na , "     -------- pSD-1   ", color.gray, DEFAULT_LABEL_STYLE, DEFAULT_LABEL_SIZE) 

pd = plot(plot_pL2 ? ps2dn : na, title = "Previous VWAP - STDEV -2", color = color.blue, style = plot.style_linebr, linewidth = 1, transp = 70)
f_drawLabel(ll_offset, show_plabels and plot_pL2 ? ps2dn : na , "     -------- pSD-2   ", color.blue, DEFAULT_LABEL_STYLE, DEFAULT_LABEL_SIZE) 

fill(pa, pb, fill_pbands ? fill_col_up : na)
fill(pb, pc, fill_pbands ? fill_col_mid : na)
fill(pc, pd, fill_pbands ? fill_col_down : na)```

Solution

You can use the compute_stDEV function, with new values

stDevMultiplier_3 = input(3.0, "StDev mult 3")
stDevMultiplier_4 = input(4.0, "StDev mult 4")

[s4up, s3up, s3dn, s4dn] = compute_stDEV(vwap_sel, stdev_sel, stDevMultiplier_3, stDevMultiplier_4)

plot(showStd ? s4up : na, title = "VWAP - STDEV +4", color = color.purple, style = plot.style_linebr, linewidth = 3, transp = 60)
plot(showStd ? s3up : na, title = "VWAP - STDEV +3", color = color.aqua,   style = plot.style_linebr, linewidth = 3, transp = 60)
plot(showStd ? s3dn : na, title = "VWAP - STDEV -3", color = color.aqua,   style = plot.style_linebr, linewidth = 3, transp = 60)
plot(showStd ? s4dn : na, title = "VWAP - STDEV -4", color = color.purple, style = plot.style_linebr, linewidth = 3, transp = 60)