nroot().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:    nRoot()
//  Author/Uploader: Antonio Marra 
//  E-mail:          [e-mail]
//  Date/Time Added: 2004-07-20 15:08:34
//  Origin:          
//  Keywords:        root sqrt
//  Level:           basic
//  Flags:           showemail,function
//  Formula URL:     http://www.amibroker.com/library/formula.php?id=366
//  Details URL:     http://www.amibroker.com/library/detail.php?id=366
//
//------------------------------------------------------------------------------
//
//  This function calculates the n-root of a number or array.
//
//------------------------------------------------------------------------------

/*_______________________________________________________________________________________ 

  SYNTAX:
         nRoot(index,number)
  
  PURPOSE:
          This function calculates the n-root of a number or array.
          The n-root of a negative number returns a zero value. 
  
  HOW TO USE:
          Copy this file in your "include" directory or append it to another file
          that You use as "functions database".

  EXAMPLE:
          1. if you want to calculate the square-root of 100, you can use
             indifferently:

             Square_root = Sqrt(100);
             or
             n_Root = nRoot(2,100);

          2. if you want to calculate the cube-root of 100 or whatever:

             n_Root = nRoot(3,100);
             n_Root = nRoot(10,100);
             n_Root = nRoot(-2,Close);

  ______________________________________________________________________________________  
                                                                                        */

Function nRoot(index,number)
{    
    cond_r = index == 0 or number == 0 or number < 0;
    If_True = 0;
    If_False = (Exp ( (1 / index) * Log(number)));
    result = iif(cond_r, If_True, If_False);
    
    Return result;
}