How to give an indicator my own data? - page 3

[nadiawicket]

Lakshan Perera:

if you want to give custom values for EMA (for any MA for that matter) use iMAOnArray()

https://docs.mql4.com/indicators/imaonarray

//+------------------------------------------------------------------+
//|                                                 ima_on_array.mq4 |
//|                        Copyright 2017, MetaQuotes Software Corp. |
//|                                             https://www.mql5.com |
//+------------------------------------------------------------------+
#property copyright "Copyright 2017, MetaQuotes Software Corp."
#property link      "https://www.mql5.com"
#property version   "1.00"
#property strict

double custom_close[13];
double ima_on_array_data;
double default_ema;
//+------------------------------------------------------------------+
//| Expert initialization function                                   |
//+------------------------------------------------------------------+
int OnInit()
  {
//---

//---
   return(INIT_SUCCEEDED);
  }
//+------------------------------------------------------------------+
//| Expert deinitialization function                                 |
//+------------------------------------------------------------------+
void OnDeinit(const int reason)
  {
//---

  }
//+------------------------------------------------------------------+
//| Expert tick function                                             |
//+------------------------------------------------------------------+
void OnTick()
  {
//---
   default_ema=iMA(_Symbol,PERIOD_M1,12,0,MODE_EMA,PRICE_CLOSE,0);

   custom_close[0]=Close[0];
   custom_close[1]=Close[1];
   custom_close[2]=Close[2];
   custom_close[3]=Close[3];
   custom_close[4]=Close[4];
   custom_close[5]=Close[5];
   custom_close[6]=Close[6];
   custom_close[7]=Close[7];
   custom_close[8]=Close[8];
   custom_close[9]=Close[9];
   custom_close[10]=Close[10];
   custom_close[11]=Close[11];
   custom_close[12]=Close[12];

//ima_on_array_data=iMAOnArray(Close,0,12,0,MODE_EMA,0);
   ima_on_array_data=iMAOnArray(custom_close,0,12,0,MODE_EMA,0);
   Print("ima on array adata = ",ima_on_array_data);
   Print("default_ema = ",default_ema);
  }
//+------------------------------------------------------------------+

Why does that code not work?

[nadiawicket]

//+------------------------------------------------------------------+
//|                                                whereitwillbe.mq4 |
//|                        Copyright 2017, MetaQuotes Software Corp. |
//|                                             https://www.mql5.com |
//+------------------------------------------------------------------+
#property copyright "Copyright 2017, MetaQuotes Software Corp."
#property link      "https://www.mql5.com"
#property version   "1.00"
#property strict

double MaBuffer[13];
int x;
double custom_close[13];
//+------------------------------------------------------------------+
//| Expert initialization function                                   |
//+------------------------------------------------------------------+
int OnInit()
  {
//---

//---
   return(INIT_SUCCEEDED);
  }
//+------------------------------------------------------------------+
//| Expert deinitialization function                                 |
//+------------------------------------------------------------------+
void OnDeinit(const int reason)
  {
//---

  }
//+------------------------------------------------------------------+
//| Expert tick function                                             |
//+------------------------------------------------------------------+
void OnTick()
  {
//---

   custom_close[0]=Close[0];
   custom_close[1]=Close[1];
   custom_close[2]=Close[2];
   custom_close[3]=Close[3];
   custom_close[4]=Close[4];
   custom_close[5]=Close[5];
   custom_close[6]=Close[6];
   custom_close[7]=Close[7];
   custom_close[8]=Close[8];
   custom_close[9]=Close[9];
   custom_close[10]=Close[10];
   custom_close[11]=Close[11];
   custom_close[12]=Close[12];

   x=0;
   MaBuffer[x]=ExponentialMA(x,12,MaBuffer[x-1],custom_close);        //MaBuffer0[i-1] (or [i+1]) = prev_value 

  }
//+------------------------------------------------------------------+
double ExponentialMA(const int position,const int period,const double prev_value,const double &price[])
  {
//---
   double result=0.0;
//--- calculate value
   if(period>0)
     {
      double pr=2.0/(period+1.0);
      result=price[position]*pr+prev_value*(1-pr);
     }
//---
   return(result);
  }
//+------------------------------------------------------------------+

If anyone knows why this code does not work please let me know.. .

Bah just stumbled upon https://book.mql4.com/samples/icustom it looks like buffers are the issue, didn't really get that before posting. 

Missed that page. Thanks for helping me out hopefully ill sort this out soon

[Lakshan Perera]

nadiawicket:

Why does that code not work?

Set the array as series.

[nadiawicket]

Lakshan Perera:
Set the array as series.

//+------------------------------------------------------------------+
//|                                                          EMA.mq4 |
//|                                         Copyright © 2010, LeMan. |
//|                                                 [e-mail] |
//+------------------------------------------------------------------+
#property copyright "Copyright © 2010, LeMAn."
#property link      "[e-mail]"

#property indicator_chart_window
#property indicator_buffers 1

double custom_close[];
double default_ema;
double ima_on_array_data;
//+------------------------------------------------------------------+
int init()
  {
   int draw_begin;
   IndicatorDigits(MarketInfo(Symbol(),MODE_DIGITS));
//----
   SetIndexDrawBegin(0,draw_begin);
//----
   SetIndexBuffer(0,custom_close);
//----
   return(0);
  }
//+------------------------------------------------------------------+
int start()
  {

//
   ArraySetAsSeries(custom_close,true);

   custom_close[0]=Close[0];
   custom_close[1]=Close[1];
   custom_close[2]=Close[2];
   custom_close[3]=Close[3];
   custom_close[4]=Close[4];
   custom_close[5]=Close[5];
   custom_close[6]=Close[6];
   custom_close[7]=Close[7];
   custom_close[8]=Close[8];
   custom_close[9]=Close[9];
   custom_close[10]=Close[10];
   custom_close[11]=Close[11];

   ima_on_array_data=iMAOnArray(custom_close,0,12,0,MODE_EMA,0); 
   default_ema=iMA(_Symbol,PERIOD_M1,12,0,MODE_EMA,PRICE_CLOSE,0);
   
   Print("ima on array adata = ",ima_on_array_data);
   Print("default_ema = ",default_ema);



//----
   
  }

still way off

[Lakshan Perera]

nadiawicket:

still way off

did you try it on 1 min chart?, because you have set the normal iMA() to 1 min.. and the value of Close[] gives the close prices of the current time frame

[nadiawicket]

Lakshan Perera:

did you try it on 1 min chart?, because you have set the normal iMA() to 1 min.. and the value of Close[] gives the close prices of the current time frame

1m frame , yes ..

[Lakshan Perera]

nadiawicket:
1m frame , yes ..

what are the values you get?

[nadiawicket]

Lakshan Perera:

what are the values you get?

heres a screen

imaonarray is name of indicator on my computer.. .same exact code as above. .

[nadiawicket]

//+------------------------------------------------------------------+
//|                                                          EMA.mq4 |
//|                                         Copyright © 2010, LeMan. |
//|                                                 [e-mail] |
//+------------------------------------------------------------------+
#property copyright "Copyright © 2010, LeMAn."
#property link      "[e-mail]"

#property indicator_chart_window
#property indicator_buffers 1

double MA_Period12=12;
int MA_Shift12 = 0;
int SetPrice12 = 0;

double ema12;
int ExtCountedBars12=0;
double ema12_calculation;
double custom_close[];
double custom_open[];
double default_ema;
//+------------------------------------------------------------------+
int init()
  {
   IndicatorDigits(MarketInfo(Symbol(),MODE_DIGITS));

   SetIndexBuffer(0,custom_close);
   SetIndexShift(0,MA_Shift12);


   SetIndexBuffer(1,custom_open);
      SetIndexShift(1,MA_Shift12);

  }
//+------------------------------------------------------------------+
int start()
  {

   default_ema=iMA(_Symbol,PERIOD_M1,12,0,MODE_EMA,PRICE_CLOSE,0);

   custom_close[0]=Close[0];
   custom_close[1]=Close[1];
   custom_close[2]=Close[2];
   custom_close[3]=Close[3];
   custom_close[4]=Close[4];
   custom_close[5]=Close[5];
   custom_close[6]=Close[6];
   custom_close[7]=Close[7];
   custom_close[8]=Close[8];
   custom_close[9]=Close[9];
   custom_close[10]=Close[10];
   custom_close[11]=Close[11];
   custom_close[12]=Close[12];

   custom_open[0]=Open[0];
   custom_open[1]=Open[1];
   custom_open[2]=Open[2];
   custom_open[3]=Open[3];
   custom_open[4]=Open[4];
   custom_open[5]=Open[5];
   custom_open[6]=Open[6];
   custom_open[7]=Open[7];
   custom_open[8]=Open[8];
   custom_open[9]=Open[9];
   custom_open[10]=Open[10];
   custom_open[11]=Open[11];
   custom_open[12]=Open[12];



   if(Bars <= MA_Period12) return(0);
   ExtCountedBars12=IndicatorCounted();
   if(ExtCountedBars12 < 0) return(-1);
   if(ExtCountedBars12>0) ExtCountedBars12--;
//----
   ema12_function();
   double pr12;
   pr12=2.0/(MA_Period12+1);
   int pos12=Bars-2;
   if(ExtCountedBars12>2) pos12=Bars-ExtCountedBars12-1;
//---- main calculation loop
   while(pos12>=0)
     {
      if(pos12==Bars-2)
         custom_close[pos12+1]=(Open[pos12+1]+custom_close[pos12+1])/2;
      custom_close[pos12]=GetPrice12(pos12)*pr12+custom_close[pos12+1]*(1-pr12);
      pos12--;
      ema12_calculation=(custom_close[pos12]);
      ema12=NormalizeDouble(ema12_calculation,Digits+1);
      Print("!!!!ema12 = ",ema12);
      return(0);
     }
  }
//----
void ema12_function()
  {
   double pr12;
   pr12=2.0/(MA_Period12+1);
   int pos12=Bars-2;
   if(ExtCountedBars12>2) pos12=Bars-ExtCountedBars12-1;
//---- main calculation loop
   while(pos12>=0)
     {
      if(pos12==Bars-2)
         custom_close[pos12+1]=(Open[pos12+1]+custom_close[pos12+1])/2;
      custom_close[pos12]=GetPrice12(pos12)*pr12+custom_close[pos12+1]*(1-pr12);
      pos12--;
     }
  }
//+------------------------------------------------------------------+
double GetPrice12(int shift12)
  {
   double price12;
   price12=custom_close[shift12];
   return(price12);
  }
//+------------------------------------------------------------------+

Why oh why does this previous code not just work, its got the buffered array and everything. Looks like I need to assign a value for every bar counted or something like that. .

Following MQL source doesn't set as series at all and works however I need to change the first value to a custom one so I can see in the future:

//+------------------------------------------------------------------+
//|                                                          EMA.mq4 |
//|                                         Copyright © 2010, LeMan. |
//|                                                 [e-mail] |
//+------------------------------------------------------------------+
#property copyright "Copyright © 2010, LeMAn."
#property link      "[e-mail]"

#property indicator_chart_window
#property indicator_buffers 1

double MA_Period12=12;
int MA_Shift12 = 0;
int SetPrice12 = 0;
double ExtMapBuffer12[];
double ema12;
int ExtCountedBars12=0;
double ema12_calculation;
double custom_close[];
double default_ema;
//+------------------------------------------------------------------+
int init()
  {
   IndicatorDigits(MarketInfo(Symbol(),MODE_DIGITS));
   SetIndexShift(0,MA_Shift12);
   SetIndexBuffer(0,ExtMapBuffer12);
  }
//+------------------------------------------------------------------+
int start()
  {
  
  default_ema=iMA(_Symbol,PERIOD_M1,12,0,MODE_EMA,PRICE_CLOSE,0);
    
   if(Bars <= MA_Period12) return(0);
   ExtCountedBars12=IndicatorCounted();
   if(ExtCountedBars12 < 0) return(-1);
   if(ExtCountedBars12>0) ExtCountedBars12--;
//----
   ema12_function();
   double pr12;
   pr12=2.0/(MA_Period12+1);
   int pos12=Bars-2;
   if(ExtCountedBars12>2) pos12=Bars-ExtCountedBars12-1;
//---- main calculation loop
   while(pos12>=0)
     {
      if(pos12==Bars-2)
         ExtMapBuffer12[pos12+1]=(Open[pos12+1]+Close[pos12+1])/2;
      ExtMapBuffer12[pos12]=GetPrice12(pos12)*pr12+ExtMapBuffer12[pos12+1]*(1-pr12);
      pos12--;
      ema12_calculation=(ExtMapBuffer12[pos12]);
      ema12=NormalizeDouble(ema12_calculation,Digits);
      Print("default_ema  = ", default_ema , "ema12 = ", ema12);
      return(0);
     }
  }
//----
void ema12_function()
  {
   double pr12;
   pr12=2.0/(MA_Period12+1);
   int pos12=Bars-2;
   if(ExtCountedBars12>2) pos12=Bars-ExtCountedBars12-1;
//---- main calculation loop
   while(pos12>=0)
     {
      if(pos12==Bars-2)
         ExtMapBuffer12[pos12+1]=(Open[pos12+1]+Close[pos12+1])/2;
      ExtMapBuffer12[pos12]=GetPrice12(pos12)*pr12+ExtMapBuffer12[pos12+1]*(1-pr12);
      pos12--;
     }
  }
//+------------------------------------------------------------------+
double GetPrice12(int shift12)
  {
   double price12;
   price12=Close[shift12];
   return(price12);
  }
//+------------------------------------------------------------------+

So Im just running these 2 side by side trying to replicate the exact value of the normal one (second one posted),  still no luck. Looks like its the bars counted thing

[Lakshan Perera]

nadiawicket:

heres a screen

imaonarray is name of indicator on my computer.. .same exact code as above. .

instead of copying the each Close value, try using this

ArrayCopy(custom_close,Close,0,0,WHOLE_ARRAY);

Or just use

CopyClose(Symbol(),PERIOD_M1,0,iBars(Symbol(),PERIOD_M1),custom_close);