indicator not working correctly

[dido]

Hi-
I'm having trouble getting this Fisher xform indicator to update accurately on my tick charts (any charts). Any ideas would be helpful.
Thanks
D.

function preMain()
{
    setStudyTitle("Fisher XForm");
    setCursorLabelName("Fisher", 0);
    setCursorLabelName("Trigger", 1);
    addBand(0, PS_SOLID, 1, Color.aqua);
    setDefaultBarFgColor(Color.green, 0);
    setDefaultBarFgColor(Color.red, 1);
    setDefaultBarThickness(1,0);
    setDefaultBarThickness(1,1);
}
var Value1_1 = 0;
var Fish_1 = 0
function main(Len) {
 if (Len == null)
  Len = 15;
 
 var Price = (high() + low()) / 2;
 var MaxH = 0;
 var MinL = 0;
 var Fish = 0;
 var i;
 var Value1 = 0;
 var temp;
 
 for(i = 0; i < Len; i++)
          if(i == 0){
   MaxH = high();
   MinL = low()
  }else{
   MaxH = Math.max(MaxH, high(-i));
   MinL = Math.min(MinL, low(-i));
  }
 
 Value1 = .33 * 2 * ((Price - MinL) / (MaxH - MinL) - .5) + .67 * Value1_1;
 
 if(Value1 > .99)
  Value1 = 9.999;
 if(Value1 < -.99)
  Value1 = -9.999;
 
 Fish = .5 * Math.log((1 + Value1) / (1 - Value1)) + .5 * Fish_1;
 
 Value1_1 = Value1;
 if(getBarState() == BARSTATE_NEWBAR) {
  temp = Fish_1;
  Fish_1 = Fish;
 }
 return new Array(Fish,temp);
} 

[ACM]

dido
The simplest solution is to use the Fisher.efs that is posted here (which also works in multiple time frames)
However if you are still interested in understanding why the version you posted is not working correctly I can guide you through fixing it
Alex

[dido]

thanks

thanks alex, that was helpful.
D

[dido]

difference in scripts

Alex-
Any idea why and if there is a difference in the script Fisher efs and Fisher xform?
I downloaded the updated link you attached for the Fisher efs and it appears to be similar but the new Fisher efs looks much more noisy(choppy) on my chart than the Fisher xform that I posted here earlier. I've tried adjusting the settings on the new one so it would match xform but can't get it to look the same. Maybe this xform is a slightly different script than the regular Fisher efs?
Any ideas and thanks for your help.
Dido

[ACM]

dido
Aside from the errors that cause the formula you posted to compute incorrectly in real time that formula is using the High and Low as MaxH and MinL regardless of the price source used whereas these should be the highest and lowest values of the price source (see here the original article by John Ehlers).
Alex