How to convert indicator(e.g Regression indicator ) to function that return a value(e.g. regression value)

[fsin100]

//+------------------------------------------------------------------+

//|                                             Vinin HighLow v1.mq4 |

//|                                        Victor Nicolaev aka Vinin |

//|                                                    [e-mail] |

//+------------------------------------------------------------------+

#property copyright "Victor Nicolaev aka Vinin"

#property link      "mailto: [e-mail]"



#property indicator_chart_window

#property indicator_buffers 3

#property indicator_color1 Yellow

#property indicator_color2 Green

#property indicator_color3 Red



extern int period=34;

extern int price=0;

extern int Shift=0;

extern int Shift=0;



//---- buffers

double BufferGreen[];

double BufferYellow[];

double BufferRed[];

//+------------------------------------------------------------------+

//| Custom indicator initialization function                         |

//+------------------------------------------------------------------+

int init() {

   int i;

   for (i=0;i<3;i++) {

      SetIndexStyle(i,DRAW_LINE);

      SetIndexDrawBegin(i,period);

      SetIndexShift(i,Shift);

   }

   SetIndexBuffer(0,BufferYellow);

   SetIndexBuffer(1,BufferGreen);

   SetIndexBuffer(2,BufferRed);

   return(0); }//int init() 

//+------------------------------------------------------------------+

int start() {

   int limit;

   double tmp1,tmp2,tmp3;

   int tmpBar, tmpTime;

   int counted_bars=IndicatorCounted();

   int i, j,k;

   if(counted_bars<0) return(-1);

   if(counted_bars>0) counted_bars--;

   limit=Bars-counted_bars;

   int cmd;

   for (i = limit;i>=0;i--){

      tmp1=iMA(Symbol(),0,period,0,MODE_SMA,price,i);

      tmp2=iMA(Symbol(),0,period,0,MODE_LWMA,price,i);

      tmp3=3.0*tmp2-2.0*tmp1;

      BufferGreen[i] =tmp3;

      BufferYellow[i]=tmp3;

      BufferRed[i]   =tmp3;

//2018-10-1 plan to enhance  Begin enhancement 

if (i==1) // to return the latest  regression value

{        

  Return_value =tmp3;        //2008-10-01 how do I pass the return_value to calling program ?  ***

}

//2018-10-1 plan to enhance  End enhancement 



      if (BufferYellow[i]>BufferYellow[i+1]){

         BufferRed[i]=EMPTY_VALUE;

      } else if (BufferYellow[i]<BufferYellow[i+1]){

         BufferGreen[i] =EMPTY_VALUE;

      } else {

         BufferRed[i]=EMPTY_VALUE;         

         BufferGreen[i] =EMPTY_VALUE;

      }

   }

   return(0); 

}

Hi all,

Good day.

GENERICALLY, how do we modify an indicator to a become a function that **return a value** to calling program ?

so that e.g. from the main program, we can call this EXAMPLE function to get a value e.g. linear-regression-indikator value 

Just using this indicator to learn how to convert to function

In main program e.g. when condition-1 met, I like to call this linear-regression-indikator to get the regression value and get the 

 double Return_val=iCustom("SP-DEC18",0,"linear-regression-indikator",34,0,0);

This is just a example function to be called

Currently the linear-regression-indikator has parameters

extern int period=34;

extern int price=0;

extern int Shift=0;

---===  sample indicator  script attached  ====

..

   int cmd;

   for (i = limit;i>=0;i--){

      tmp1=iMA(Symbol(),0,period,0,MODE_SMA,price,i);

      tmp2=iMA(Symbol(),0,period,0,MODE_LWMA,price,i);

      tmp3=3.0*tmp2-2.0*tmp1;

      BufferGreen[i] =tmp3;

      BufferYellow[i]=tmp3;

      BufferRed[i]   =tmp3;

//2018-10-1 plan to enhance  Begin enhancement 

if (i==1) // to return the latest  regression value

{  

  Return_value =tmp3;        //2008-10-01 how do I pass the return_value to calling program ?  ***

}

//2018-10-1 plan to enhance  End enhancement 

      if (BufferYellow[i]>BufferYellow[i+1]){

         BufferRed[i]=EMPTY_VALUE;

      } else if (BufferYellow[i]<BufferYellow[i+1]){

         BufferGreen[i] =EMPTY_VALUE;

      } else {

         BufferRed[i]=EMPTY_VALUE;         

         BufferGreen[i] =EMPTY_VALUE;

      }

   }

   return(0); 

}

==== Note: Reference for icustom======

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

double  iCustom(
   string       symbol,           // symbol
   int          timeframe,        // timeframe
   string       name,             // path/name of the custom indicator compiled program
   ...                            // custom indicator input parameters (if necessary)
   int          mode,             // line index
   int          shift             // shift
   );

Thank you very much in advance

/

[Sergey Golubev]

Forum on trading, automated trading systems and testing trading strategies

When you post code please use the CODE button (Alt-S)!

Thank you.

[fsin100]

Noted. Thank you