firstbarindex(), lastbarindex().afl

一个更精度的平滑涵数, 可用于股票交易系统.用于Amibroker 平台

//------------------------------------------------------------------------------
//
//  Formula Name:    FirstBarIndex(), LastBarIndex()
//  Author/Uploader: Antonio Marra 
//  E-mail:          [e-mail]
//  Date/Time Added: 2004-07-20 06:38:08
//  Origin:          
//  Keywords:        BarIndex
//  Level:           basic
//  Flags:           showemail,function
//  Formula URL:     http://www.amibroker.com/library/formula.php?id=363
//  Details URL:     http://www.amibroker.com/library/detail.php?id=363
//
//------------------------------------------------------------------------------
//
//  It retrieve the first or the last BarIndex() Value when a given condition
//  is true.
//
//------------------------------------------------------------------------------

/*_________________________________________________________________________________________ 

  SYNTAX:
         FirstBarIndex(Condition)
         LastBarIndex(Condition)
  
  PURPOSE:
          It gets the first BarIndex() Value when a given condition is true.
          It gets the last BarIndex() Value when a given condition is true.
  
  HOW TO USE:
          Copy this file in your include directory or append it to another file that You 
          use as "functions database".

  EXAMPLE:
          1. Let's suppose you want to know when a given condition comes true for the
             first time and for the last time.
             
             //We will serch for the first and last DOJI candle
             // Condition is:
             Doji = (O == C and O < H and O > L);
             
             First_Bar = FirstBarIndex(Doji);
             First_Doji_Close = ValueWhen( BarIndex()== First_Bar,C,1);
             
             Last_Bar = LastBarIndex(Doji);
             Last_Doji_Close = ValueWhen( BarIndex()== Last_Bar,C,1);
          

  ________________________________________________________________________________________  
                                                                                          */
                                                                                          
                                                                                          
function FirstBarIndex(Condition)
{
     TotalBarsIndex = LastValue(BarIndex());
     a = 0;
     Counter = 0;
     for (a = 0 ;a < TotalBarsIndex; a++)
     {
       Counter = Counter+1;
       if (
           IsTrue(Condition[a])
          )
       a = TotalBarsIndex;
       }
     result = Counter-1;

     return result;
}




function LastBarIndex(Condition)
{
     TotalBarsIndex = LastValue(BarIndex());
     a = TotalBarsIndex;
     Counter = TotalBarsIndex+1;
     for (a = TotalBarsIndex ;a > 0; a--)
     {
       Counter = Counter-1;
       if (
           IsTrue(Condition[a])
          )
       a = 0;
     }
     result = Counter;

     return result;
}