//+---------------------------------------------------------------------+
//|                                                  ZP_WPR-OBV_v02.mq4 |
//|                                       Copyright © 2009, Ron Mauldin |
//|                                                                     |
//| William's Percent Range Crossed With On Balance Volume              |
//|                                                                     |
//| This indicator is a modification of William's Percent Range.        |
//| In WPR, I replaced the 'period close' with On Balance Volume.       |
//| This was simply a way to introduce volume into my favorite          |
//| indicator.
//| The outcome is very interesting with mixed results.                 |
//| • On the plus side, it is like an enhanced WPR in that it is        |
//|   still a leading signal that usually leads even WPR.               |
//| • On the minus side, sometimes it gives totally bogus signals.      |
//| If you figure out how to stop the bogus signals or can even         |
//| Identify what causes the bogus signals... please drop me a line.    |
//|                                                                     |
//| Collaborators Wanted                                                |
//| Do you have an interesting idea or indicator designed for scalping? |
//| Would you like to collaborate and turn it into an EA trading robot? |
//| If I like your idea, I will help you fully analyze it.              |
//| If the analysis is good, then I will help you turn your idea into   |
//| an EA robot that we will both share.                                |
//|                                                                     |
//| Are you a "quality" MT4 programmer with "plenty of time" to work on |
//| joint venture (JV) projects?                                        |
//| If so, I have plenty of ideas and would like to discuss a JV.       |
//|                                                                     |
//|  NOTE!!!                                                            |
//|  I am NOT looking for back-testers or programmers for hire.         |
//|  I am looking for entrepreneurial technical analysts or programmers |
//|  who really believe that well coded forex robot could make millions.|
//|  Please don't yank my chain if you are not serious about hard work. |
//|                                                                     |
//| Email: ronmauldin51-mt4 at yahoo dot com                            |
//|                                                                     |
//| This is the forex broker I use: fx41.com                            |
//+---------------------------------------------------------------------+
#property  copyright "Copyright © 2009, Ron Mauldin"
#property  link      "ronmauldin51-mt4 at yahoo dot com"

#property indicator_separate_window
#property indicator_minimum -100
#property indicator_maximum 0
#property indicator_buffers 2
#property indicator_color1 Black
#property indicator_color2 DodgerBlue
#property indicator_level1 -20
#property indicator_level2 -80


extern int WPR_Period = 6;
//---- buffers
double obvBuffer[];
double wprBuffer[];
//+------------------------------------------------------------------+
//| ZP_WPR-OBV indicator initialization function                         |
//+------------------------------------------------------------------+
int init(){
 IndicatorShortName("ZP_WPR-OBV("+WPR_Period+")");
 IndicatorBuffers(2);
 SetIndexBuffer(0,obvBuffer);
 SetIndexStyle(0,DRAW_LINE);
 SetIndexLabel(0,"OBV");
 SetIndexBuffer(1,wprBuffer);
 SetIndexStyle(1,DRAW_LINE);
 SetIndexLabel(1,"WPR-OBV");
 return(0);
}
//+------------------------------------------------------------------+
//| WPR Using On Balance Volume                                          |
//+------------------------------------------------------------------+
int start(){
// int    bar,nLimit,nCountedBars;

 //Indicator Variables
 double obvOpen,obvClose;
 double obvMaxHigh,obvMinLow;
 
 // Standard variables
 int bar,MaxBar, limit, counted_bars = IndicatorCounted();

 // Standard loop setup
 MaxBar=WPR_Period;
 if(Bars-1 < MaxBar) return(0);
 if(counted_bars < 0) return(-1);
 if(counted_bars > 0) counted_bars--;
 MaxBar = Bars - 1 - MaxBar;
 limit = (Bars - 1 - counted_bars);
   
 //---- initialization of buffer nulls
 if(limit > MaxBar){
  for(bar = Bars - 1; bar >= MaxBar; bar--) {
   obvBuffer[bar] = 0.0;
   wprBuffer[bar] = 0.0;
  }
  limit = MaxBar; 
 }

 //+--- Basic loop to populate the OBV buffer
 for(bar = limit; bar >= 0; bar--){
  if(bar==Bars-1)obvBuffer[bar]=Volume[bar];
  else{
   obvOpen=Close[bar+1];
   obvClose=Close[bar];
   if(obvClose==obvOpen)obvBuffer[bar]=obvBuffer[bar+1];
   else if(obvClose<obvOpen)obvBuffer[bar]=obvBuffer[bar+1]-Volume[bar];  
   else obvBuffer[bar]=obvBuffer[bar+1]+Volume[bar]; 
  }
 }

 //+--- Basic loop to calcute WPR-OBV
 for(bar = limit; bar >= 0; bar--){
  obvMaxHigh = obvBuffer[ArrayMaximum(obvBuffer,WPR_Period,bar)];
  obvMinLow  = obvBuffer[ArrayMinimum(obvBuffer,WPR_Period,bar)];
  if(!CompareDouble((obvMaxHigh - obvMinLow), 0.0))
   wprBuffer[bar] = -100*(obvMaxHigh - obvBuffer[bar]) / (obvMaxHigh - obvMinLow);
 }
 
 return(0);
}
//+------------------------------------------------------------------+
bool CompareDouble(double Number1, double Number2)
  {
    bool Compare = NormalizeDouble(Number1 - Number2, 8) == 0;
    return(Compare);
  } 
//+------------------------------------------------------------------+