mql5 standard deviation channel formula code -good coder wanted

[Roler100]

Hi all,

does any one know what formula is used in creating the mql5 standard deviation channels object OBJ_STDDEVCHANNEL and how this formula can be coded from first principles in mql5 to derive the channel values.

I think this could be a freelance opportunity for some one with this knowledge

[William Roeder]

      // Standard deviation - //en.wikipedia.org/wiki/Standard_deviation
      // SMA = 1/n sum(X)
      // Std = Sqrt[1/n sum{(x-sma)^2}] = Sqrt[1/n Sum(x^2)-(1/n Sum(x))^2]
      double   sumX  = 0.0, sumX2   = 0.0;
      for(INDEX i=iBar+agkLength; i>iBar;){  --i;
         CHANGE   tr = TRD(i);   sumX += tr; sumX2 += tr * tr;
      }
      double      sma   = sumX / agkLength,
                  std   = MathSqrt(sumX2/agkLength - atr*atr);

[Roler100]

William Roeder #:

Thanks William,

I will work on this.

Its a pity that the standard deviation channel values are not directly calculable in mql5 as they are for so many other indicators such as the MA functions.

btw are you available for freelance coding?

best regards.