source question

[rainwater88]

Hello,
I added some function parameters to this EFS and would like to be able to use high + low + (2*close)/4 as one of the sources for the CCI, if not the only choice, but I don't seem to be able to get it to work, it comes up blank.
Also when I try to add direction color to the line it goes blank as well.
Any help would be greatly appreciated.

/*********************************************************
By Alexis C. Montenegro December 2004                     
Use and/or modify this code freely. If you redistribute it
please include this and/or any other comment blocks and a 
description of any changes you make.                      
**********************************************************/
var fpArray = new Array();
function preMain() {
    setPriceStudy(false);
    setStudyTitle("CCI adj");
    setCursorLabelName("CCI adj", 0);
    setDefaultBarFgColor(Color.yellow, 0);
    setPlotType(PLOTTYPE_LINE,0);
    setDefaultBarThickness(1,0);
    setStudyMin(-220);
    setStudyMax(220);
    addBand(200, PS_DOT, 2, Color.grey,"200");
    addBand(100, PS_DOT, 2, Color.green,"100");
    addBand(0, PS_DASH, 2, Color.grey,"zero");
    addBand(-100, PS_DOT, 2, Color.green,"-100");
    addBand(-200, PS_DOT, 2, Color.grey,"-200"); 
    askForInput();
    var x=0;
    fpArray[x] = new FunctionParameter("Length", FunctionParameter.NUMBER);
    with(fpArray[x++]){
        setLowerLimit(1);        
        setDefault(20);
    }
    fpArray[x] = new FunctionParameter("Source", FunctionParameter.STRING);
    with(fpArray[x++]){
        addOption("open"); 
        addOption("high");
        addOption("low");
        addOption("close");
        addOption("hl2");
        addOption("hlc3");
        addOption("ohlc4");
        //Is there any way to add HLCC option here ?
        //addOption("hlcc4");
        setDefault("hlc3"); 
    }
    fpArray[x] = new FunctionParameter("Type", FunctionParameter.STRING);
    with(fpArray[x++]){
        addOption("sma");
        addOption("ema");
        addOption("wma");
        addOption("vwma");
        setDefault("sma");
    }
    fpArray[x] = new FunctionParameter("Multiplier", FunctionParameter.NUMBER);
    with(fpArray[x++]){
        setLowerLimit(0.001);        
        setDefault(0.015);
    }
}
var bInit = false;
var xPrice = null;
var xAvgPrice = null;
var xMulti = null;
var xCCI = null;
//var xHLCC = null;
function main(Length, Source, Type, Multiplier){
    if(bInit == false){ 
    //Tried to add new source here
    //xHLCC = (high(0)+low(0)+(2*close(0)))/4; 
    //xPrice = xHLCC;
    xPrice = eval(Source)();
    xAvgPrice = eval(Type)(Length,xPrice);
    xMulti = Multiplier;
    bInit = true;
    }
    if(xPrice.getValue(-Length)==null||xAvgPrice.getValue(-Length)==null) return;
    var Sum = 0;
    for (var i=0; i<Length; i++){
        Sum += Math.abs(xPrice.getValue(-i)-xAvgPrice.getValue(0));
    }
    var MeanDevPrice = Sum/Length;
    var xCCI = (xPrice.getValue(0)-xAvgPrice.getValue(0))/(MeanDevPrice*xMulti);
    //CCI color change with direction change
    /*if(xCCI.getValue(0) > xCCI.getValue(-1)) {
        setBarFgColor(Color.green,0);
            } else setBarFgColor (Color.red,0);*/
    return xCCI;    
} 

[ACM]

Re: source question

rainwater88
The reason your script is not working is because hlcc4 is not a valid source as there is no such function.
In order to do what you want you will need to calculate your custom source in a separate function or efs and then call that function or efs from inside main() using either the efsInternal() or efsExternal() functions (see the links to the corresponding article in the EFS KnowledgeBase for the descripotion and syntax of these functions). This will create the series which you can then use as a source for the moving average functions used to calculate xAvgPrice
For a more detailed explanation and solution see this post in reply to a similar question. In that reply you will also find links to other examples on creating studies on studies or custom variables using efs2 functions
Alex

Originally posted by rainwater88
Hello,
I added some function parameters to this EFS and would like to be able to use high + low + (2*close)/4 as one of the sources for the CCI, if not the only choice, but I don't seem to be able to get it to work, it comes up blank.
Also when I try to add direction color to the line it goes blank as well.
Any help would be greatly appreciated.

/*********************************************************
By Alexis C. Montenegro December 2004                     
Use and/or modify this code freely. If you redistribute it
please include this and/or any other comment blocks and a 
description of any changes you make.                      
**********************************************************/
var fpArray = new Array();
function preMain() {
    setPriceStudy(false);
    setStudyTitle("CCI adj");
    setCursorLabelName("CCI adj", 0);
    setDefaultBarFgColor(Color.yellow, 0);
    setPlotType(PLOTTYPE_LINE,0);
    setDefaultBarThickness(1,0);
    setStudyMin(-220);
    setStudyMax(220);
    addBand(200, PS_DOT, 2, Color.grey,"200");
    addBand(100, PS_DOT, 2, Color.green,"100");
    addBand(0, PS_DASH, 2, Color.grey,"zero");
    addBand(-100, PS_DOT, 2, Color.green,"-100");
    addBand(-200, PS_DOT, 2, Color.grey,"-200"); 
    askForInput();
    var x=0;
    fpArray[x] = new FunctionParameter("Length", FunctionParameter.NUMBER);
    with(fpArray[x++]){
        setLowerLimit(1);        
        setDefault(20);
    }
    fpArray[x] = new FunctionParameter("Source", FunctionParameter.STRING);
    with(fpArray[x++]){
        addOption("open"); 
        addOption("high");
        addOption("low");
        addOption("close");
        addOption("hl2");
        addOption("hlc3");
        addOption("ohlc4");
        //Is there any way to add HLCC option here ?
        //addOption("hlcc4");
        setDefault("hlc3"); 
    }
    fpArray[x] = new FunctionParameter("Type", FunctionParameter.STRING);
    with(fpArray[x++]){
        addOption("sma");
        addOption("ema");
        addOption("wma");
        addOption("vwma");
        setDefault("sma");
    }
    fpArray[x] = new FunctionParameter("Multiplier", FunctionParameter.NUMBER);
    with(fpArray[x++]){
        setLowerLimit(0.001);        
        setDefault(0.015);
    }
}
var bInit = false;
var xPrice = null;
var xAvgPrice = null;
var xMulti = null;
var xCCI = null;
//var xHLCC = null;
function main(Length, Source, Type, Multiplier){
    if(bInit == false){ 
    //Tried to add new source here
    //xHLCC = (high(0)+low(0)+(2*close(0)))/4; 
    //xPrice = xHLCC;
    xPrice = eval(Source)();
    xAvgPrice = eval(Type)(Length,xPrice);
    xMulti = Multiplier;
    bInit = true;
    }
    if(xPrice.getValue(-Length)==null||xAvgPrice.getValue(-Length)==null) return;
    var Sum = 0;
    for (var i=0; i<Length; i++){
        Sum += Math.abs(xPrice.getValue(-i)-xAvgPrice.getValue(0));
    }
    var MeanDevPrice = Sum/Length;
    var xCCI = (xPrice.getValue(0)-xAvgPrice.getValue(0))/(MeanDevPrice*xMulti);
    //CCI color change with direction change
    /*if(xCCI.getValue(0) > xCCI.getValue(-1)) {
        setBarFgColor(Color.green,0);
            } else setBarFgColor (Color.red,0);*/
    return xCCI;    
} 

[rainwater88]

Thank you Alexis

I used the EFSInternal

xPrice = EFSInternal("xHLLCC")
xHLCC function() {
return((high(0)+low(0)+(2*close(0)))/4;
}
works good.

With the formula as is below when I try to add direction color to the line, (bottom blocked out code), it goes blank, any suggestions ?

Thanks again for you help.

[ACM]

rainwater88
The reason why the script is not working when you uncomment that section of code is because in the condition to color the plot ie
if(xCCI.getValue(0) > xCCI.getValue(-1)) {
you are trying to retrieve the current and previous values of xCCI using the .getValue() method which is invalid since xCCI is not a series but a single value. In this case the simplest solution is to use one of methods suggested in this post.
Alex

Originally posted by rainwater88
Thank you Alexis

I used the EFSInternal

xPrice = EFSInternal("xHLLCC")
xHLCC function() {
return((high(0)+low(0)+(2*close(0)))/4;
}
works good.

With the formula as is below when I try to add direction color to the line, (bottom blocked out code), it goes blank, any suggestions ?

Thanks again for you help.

[rainwater88]

Thanks Alex, I managed to get the line red but no green though. I still must have something wrong ?

var bInit = false;
var xPrice = null;
var xAvgPrice = null;
var xMulti = null;
var xCCI = null;
var xCCI_1 = null;
function main(Length, Source, Type, Multiplier){
    if (getBarState() == BARSTATE_NEWBAR) {
    xCCI_1 = xCCI;
    }
    if(bInit == false){    
    xPrice = eval(Source)();
    xAvgPrice = eval(Type)(Length,xPrice);
    xMulti = Multiplier;
    bInit = true;
    }
    if(xPrice.getValue(-Length)==null||xAvgPrice.getValue(-Length)==null) return;
    var Sum = 0;
    for (var i=0; i<Length; i++){
        Sum += Math.abs(xPrice.getValue(-i)-xAvgPrice.getValue(0));
    }
    var MeanDevPrice = Sum/Length;
    var xCCI = (xPrice.getValue(0)-xAvgPrice.getValue(0))/(MeanDevPrice*xMulti);
    
    if(xCCI >= xCCI_1) {
        setBarFgColor(Color.green,0);
            } else setBarFgColor(Color.red,0);
    
    return xCCI;    
} 

[ACM]

rainwater88
Remove the var from the line
var xCCI = (xPrice.getValue(0)-xAvgPrice.getValue(0))/(MeanDevPrice*xMulti);
and it should work.
Alex

Originally posted by rainwater88
Thanks Alex, I managed to get the line red but no green though. I still must have something wrong ?

var bInit = false;
var xPrice = null;
var xAvgPrice = null;
var xMulti = null;
var xCCI = null;
var xCCI_1 = null;
function main(Length, Source, Type, Multiplier){
    if (getBarState() == BARSTATE_NEWBAR) {
    xCCI_1 = xCCI;
    }
    if(bInit == false){    
    xPrice = eval(Source)();
    xAvgPrice = eval(Type)(Length,xPrice);
    xMulti = Multiplier;
    bInit = true;
    }
    if(xPrice.getValue(-Length)==null||xAvgPrice.getValue(-Length)==null) return;
    var Sum = 0;
    for (var i=0; i<Length; i++){
        Sum += Math.abs(xPrice.getValue(-i)-xAvgPrice.getValue(0));
    }
    var MeanDevPrice = Sum/Length;
    var xCCI = (xPrice.getValue(0)-xAvgPrice.getValue(0))/(MeanDevPrice*xMulti);
    
    if(xCCI >= xCCI_1) {
        setBarFgColor(Color.green,0);
            } else setBarFgColor(Color.red,0);
    
    return xCCI;    
} 

[rainwater88]

Thank you Alex,
your very kind, I never would of figured that one out, but I am advancing my knowledge of how to work with EFS, little by little. If I may ask what is the reason for the removal ?
Here is the finished EFS
Thanks Alex

[ACM]

rainwater88
You are most welcome.
Removing the var is required because the variable xCCI needs to be declared globally (rather than locally as was the case) so that its value persists between iterations of the efs and you can transfer it to xCCI_1. If it is declared locally it will instead be undefined at the following iteration of the efs until it gets declared and a value is assigned to it
Hope this helps
Alex

Originally posted by rainwater88
Thank you Alex,
your very kind, I never would of figured that one out, but I am advancing my knowledge of how to work with EFS, little by little. If I may ask what is the reason for the removal ?
Here is the finished EFS
Thanks Alex

[ACM]

rainwater88
To illustrate what I explained in my previous reply run the following efs on a chart and open the Formula Output Window.

//global variables
var x = null;
var y = null;

function main(){

    debugPrintln("in line 6 x is = "+x);

    if(getBarState()==BARSTATE_NEWBAR){
        y = x;//value of x is transferred to y at every first tick of new bar
    }
        
    var x = close(0);//declaring locally overrides the global scope
    
    debugPrintln("in line 15 x is = "+x);
} 

You will see that on each iteration of the efs the variable x at line 6 will return undefined hence y will also be set to undefined. This is what was happening in your script prior to the correction.



Now remove the var from line 15, save the efs and reload it.



You will now see that on each iteration of the efs the variable x at line 6 will return value of x at line 15 of the prior iteration hence that value will be transferred to the variable y
Alex

[rainwater88]

Alex, Thank you for the example, I understand the difference in variable calls better now.

From the CCI efs example below could you translate this piece of code for me. I see this in many formulas, I understand the results, but don't understand the use of "i" or how the code is working.

var Sum = 0;

for (var i=0; i<Length; i++){

Sum += Math.abs(xPrice.getValue(-i)-xAvgPrice.getValue(0));

}

Thank you,
rainwater

[ACM]

rainwater
That is a for loop. In the example the variable i will hold a value that starts at 0 and keeps on incrementing by 1 on each iteration of the loop as long as i is less than the value of Length. When the value of i is equal to the value of Length the loop terminates. On each iteration of the loop it adds to the local variable Sum the result of the equation Math.abs(xPrice.getValue(-i)-xAvgPrice.getValue(0))
For a complete description of the for loop including examples on how to use it you may want to review this article of the Core JavaScript Guide which is in the EFS KnowledgeBase. The for loop is also explained in the JavaScript for EFS video series
Alex

Originally posted by rainwater88
Alex, Thank you for the example, I understand the difference in variable calls better now.

From the CCI efs example below could you translate this piece of code for me. I see this in many formulas, I understand the results, but don't understand the use of "i" or how the code is working.

var Sum = 0;

for (var i=0; i<Length; i++){

Sum += Math.abs(xPrice.getValue(-i)-xAvgPrice.getValue(0));

}

Thank you,
rainwater

[rainwater88]

Very good Alex, you have been most helpful.
This has been a great exercise to further my knowledge of EFS coding.
Sometimes it becomes a little challenging to be an affective trader and learn EFS programming at the same time. The EFS work is usually put off until later.
You make it much easier to learn the code and how it is used.
Thank you for your time and assistance.
rainwater

[ACM]

rainwater88
You are most welcome
Alex

Originally posted by rainwater88
Very good Alex, you have been most helpful.
This has been a great exercise to further my knowledge of EFS coding.
Sometimes it becomes a little challenging to be an affective trader and learn EFS programming at the same time. The EFS work is usually put off until later.
You make it much easier to learn the code and how it is used.
Thank you for your time and assistance.
rainwater