//+------------------------------------------------------------------+
//| Custom Moving Average.mq4 |
//| Copyright © 2004, MetaQuotes Software Corp. |
//| http://www.metaquotes.net/ |
//+------------------------------------------------------------------+
#property copyright "Copyright © 2004, MetaQuotes Software Corp."
#property link "http://www.metaquotes.net/"
#property indicator_chart_window
#property indicator_buffers 1
#property indicator_color1 Red
//---- indicator parameters
extern int MA_Period=13; extern int MA_Shift=0; extern int MA_Method=0; //---- indicator buffers
double ExtMapBuffer[]; //----
int ExtCountedBars=0; //+------------------------------------------------------------------+
//| Custom indicator initialization function |
//+------------------------------------------------------------------+
int init()
{
int draw_begin; string short_name; //---- drawing settings
SetIndexStyle(0,DRAW_LINE); SetIndexShift(0,MA_Shift); IndicatorDigits(MarketInfo(Symbol(),MODE_DIGITS)); if(MA_Period<2) MA_Period=13; draw_begin=MA_Period-1; //---- indicator short name
switch(MA_Method)
{
case 1 : short_name="EMA("; draw_begin=0; break; case 2 : short_name="SMMA("; break; case 3 : short_name="LWMA("; break; default : MA_Method=0; short_name="SMA("; }
IndicatorShortName(short_name+MA_Period+")"); SetIndexDrawBegin(0,draw_begin); //---- indicator buffers mapping
SetIndexBuffer(0,ExtMapBuffer); //---- initialization done
return(0); }
//+------------------------------------------------------------------+
//| |
//+------------------------------------------------------------------+
int start()
{
if(Bars<=MA_Period) return(0); ExtCountedBars=IndicatorCounted(); //---- check for possible errors
if (ExtCountedBars<0) return(-1); //---- last counted bar will be recounted
if (ExtCountedBars>0) ExtCountedBars--; //----
switch(MA_Method)
{
case 0 : sma(); break; case 1 : ema(); break; case 2 : smma(); break; case 3 : lwma(); }
//---- done
return(0); }
//+------------------------------------------------------------------+
//| Simple Moving Average |
//+------------------------------------------------------------------+
void sma()
{
double sum=0; int i,pos=Bars-ExtCountedBars-1; //---- initial accumulation
if(pos<MA_Period) pos=MA_Period; for(i=1;i<MA_Period;i++,pos--)
sum+=Close[pos]; //---- main calculation loop
while(pos>=0)
{
sum+=Close[pos]; ExtMapBuffer[pos]=sum/MA_Period; sum-=Close[pos+MA_Period-1]; pos--; }
//---- zero initial bars
if(ExtCountedBars<1)
for(i=1;i<MA_Period;i++) ExtMapBuffer[Bars-i]=0; }
//+------------------------------------------------------------------+
//| Exponential Moving Average |
//+------------------------------------------------------------------+
void ema()
{
double pr=2.0/(MA_Period+1); int pos=Bars-2; if(ExtCountedBars>2) pos=Bars-ExtCountedBars-1; //---- main calculation loop
while(pos>=0)
{
if(pos==Bars-2) ExtMapBuffer[pos+1]=Close[pos+1]; ExtMapBuffer[pos]=Close[pos]*pr+ExtMapBuffer[pos+1]*(1-pr); pos--; }
}
//+------------------------------------------------------------------+
//| Smoothed Moving Average |
//+------------------------------------------------------------------+
void smma()
{
double sum=0; int i,k,pos=Bars-ExtCountedBars+1; //---- main calculation loop
pos=Bars-MA_Period; if(pos>Bars-ExtCountedBars) pos=Bars-ExtCountedBars; while(pos>=0)
{
if(pos==Bars-MA_Period)
{
//---- initial accumulation
for(i=0,k=pos;i<MA_Period;i++,k++)
{
sum+=Close[k]; //---- zero initial bars
ExtMapBuffer[k]=0; }
}
else sum=ExtMapBuffer[pos+1]*(MA_Period-1)+Close[pos]; ExtMapBuffer[pos]=sum/MA_Period; pos--; }
}
//+------------------------------------------------------------------+
//| Linear Weighted Moving Average |
//+------------------------------------------------------------------+
void lwma()
{
double sum=0.0,lsum=0.0; double price; int i,weight=0,pos=Bars-ExtCountedBars-1; //---- initial accumulation
if(pos<MA_Period) pos=MA_Period; for(i=1;i<=MA_Period;i++,pos--)
{
price=Close[pos]; sum+=price*i; lsum+=price; weight+=i; }
//---- main calculation loop
pos++; i=pos+MA_Period; while(pos>=0)
{
ExtMapBuffer[pos]=sum/weight; if(pos==0) break; pos--; i--; price=Close[pos]; sum=sum-lsum+price*MA_Period; lsum-=Close[i]; lsum+=price; }
//---- zero initial bars
if(ExtCountedBars<1)
for(i=1;i<MA_Period;i++) ExtMapBuffer[Bars-i]=0; }
//+------------------------------------------------------------------+
