Exponential Moving Average（EMA）

Exponential Moving Average（EMA）－MetaQuotes
Exponential Moving Average（EMA）－DanielsTrading

Calculation:

Exponential Moving Average (EMA)

Exponentially smoothed moving average is calculated by adding the moving
average of a certain share of the current closing price to the previous value.
With exponentially smoothed moving averages, the latest prices are of more
value. P-percent exponential moving average will look like:

EMA = (CLOSE(i)*P)+(EMA(i-1)*(100-P))

Where:
CLOSE(i) — the price of the current period closure;
EMA(i-1) — Exponentially Moving Average of the previous period closure;
P — the percentage of using the price value.

這指標在TS內部並無內建指標，但是HTS內建有，因此在轉部份HTS
程式到TS上的時候會需要自己新增自訂函數，在這裡就直接把這部
份的程式碼直接轉成TS，使用者自己加入就可以了。

• 函數名稱取名自定，或者同HTS內建名稱：EMA
  
• 設定完後要記得按Verify（F3）

TS新增自訂函數

TS程式碼（修改HTS源碼）

Inputs: Price(Numeric), Length(Numeric);
Variables: Factor(0);

If CurrentBar = 1 Then begin
   EMA = Price;
end
Else begin
   If CurrentBar <= Length -1 Then begin     
       Factor = 2 / (CurrentBar + 1);     
       EMA = Price * Factor + (1 - Factor) * EMA[1];  
   end  
   Else begin     
       Factor = 2 / (Length + 1);                
       EMA = Factor * Price + (1 - Factor) * EMA[1];  
   end;
End;