Williams AD is the accumulated sum of positive "accumulational" and negative "distributional" price movements.
Calculation:
To calculate the accumulation/distribution indicator, first you have to find a "True Range High" (TRH) and "True Range Low" (TRL):
TRH (i) = MAX (HIGH (i) || CLOSE (i - 1))
TRL (i) = MIN (LOW (i) || CLOSE (i - 1))
Then you must find the current value of accumulation/distribution by comparing today and yesterday's closing prices.
1. If the current closing price is higher than the previous one, then:
CurА/D = CLOSE (i) - ТRL (i)
2. If the current closing price is lower than the previous one, then:
CurА/D = CLOSE (i) - ТRH (i)
3. If current and previous closing prices coincide then:
CurА/D = 0
Williams accumulation/distribution indicator is a growing sum of these values for each day:
WА/D (i) = CurА/D + WА/D (i - 1)
Where:
TRH (i) — the True Range High;
TRL (i) — the True Range Low;
MIN — the minimum value;
MAX — the maximum value;
|| — the logical OR;
LOW (i) — the minimum price of the current bar;
HIGH (i) — the maximum price of the current bar;
CLOSE (i) — the closing price of the current bar;
CLOSE (i - 1) — the closing price of the previous bar;
CurА/D — means current value of accumulation/distribution;
WА/D (i) — the current value of Williams Accumulation/Distribution indicator;
WА/D (i - 1) — the value of Williams Accumulation/Distribution indicator on the previous bar.
- Code: Select all
function Init()
indicator:name("Williams Accumulation/Distribution (WAD)");
indicator:description("Williams Accumulation/Distribution (WAD)");
indicator:requiredSource(core.Bar);
indicator:type(core.Oscillator);
indicator.parameters:addColor("clrWAD", "Color of WAD", "Color of WAD", core.rgb(0, 255, 0));
end
local first;
local source = nil;
local WAD;
function Prepare()
source = instance.source;
first=source:first()+2;
local name = profile:id() .. "(" .. source:name() .. ")";
instance:name(name);
WAD = instance:addStream("WAD", core.Line, name .. ".WAD", "WAD", instance.parameters.clrWAD, first);
end
function Update(period, mode)
if (period>first+1) then
local TRH=math.max(source.high[period],source.close[period-1]);
local TRL=math.min(source.low[period],source.close[period-1]);
local AD;
if source.close[period]>source.close[period-1]+source:pipSize() then
AD=source.close[period]-TRL;
elseif source.close[period]<source.close[period-1]-source:pipSize() then
AD=source.close[period]-TRH;
else
AD=0.;
end
WAD[period]=WAD[period-1]+AD;
else
WAD[period]=0.;
end
end
WAD.lua- (1.21 KiB) Downloaded 1515 times
- WAD Price Overlay.lua
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