Data from previous bar

[xoprofittaker]

How do I get data from the close of the previous bar???

How do I get data from the close of 2 bars ago???

Thanks,

John

[ACM]

xoprofittaker
That depends on the type of data.
If it is a series then you can access the value either directly by specifying the bar index within the function eg

var myClose1 = close(-1);//the Close at the prior bar
var myHigh2 = high(-2);//the High of two bars ago 
var myVar3 = sma(10,-3);//the value of a 10 period simple MA at three bars ago
//etc 

or you can use the getValue(-n) method where -n is the bar index eg.

var myStudy = sma(10);//declare and initialize the series
var myVar1 = myStudy.getValue(-1);//retrieves the value of myStudy one bar back
var myVar2 = myStudy.getValue(-2);//the value of myStudy two bars back
//etc 

If instead the data is not a series then see this reply to a similar question
Alex

[buzzhorton]

Alexis or anyone else:

I just can't seem to figure out SERIES data.

Everytime I think I "get" it, I run into another problem.

I must have a MENTAL BLOCK.

I want to be able to define xOPEN, xHIGH, xMIDPOINT, xLOW, and xCLOSE so I can reference values in this manner:

xMIDPOINT(-1) : previous day's midpoint

xMIDPOINT(0) : current day's midpoint.

var xInit   = false;
var xMiddle = null;

var xOpen   = null;
var xHigh   = null;
var xLow    = null;
var xClose  = null;

function main( ) {


    if(xInit==false){         


         xOpen   =  open( inv("D") ) ;

         
         xHigh   =  high( inv("D") ) ;

         xLow    =  low( inv("D") ) ;

         xClose  =  close( inv("D") ) ;

         xInit=true;

    } // xInit 


var zOpen   = xOpen.getValue(0) ;

var zClose1 = xClose.getValue(-1) ;

var zHigh   = xHigh.getValue(-1) ;

var zLow    = xLow.getValue(-1) ;

var zMid1   = rnd( ((zHigh + zLow) * .50) , 2 )   ;
var zGap    = rnd( (zOpen - zClose1) , 2) ;


debugPrint( "zMid1  xInit   : " + zMid1  + "\n" ); 
debugPrint( "zGap  xInit   : " + zGap + "\n" ); 

return ; // main

}


//==rnd will round to N digits.
function rnd(value, N) {
    var n;
    var mult=1;
    for(n=0;n<N;n++) mult*=10;
    value*=mult;
    return Math.round( value,N)/mult;
} 

From what I have read, that should create a series.

It works.

I am still baffled.

It is just not INTUITIVE.

Sometimes, I can create a series that works and sometimes what I code just doesn't work.

Why doesn't xMidpoint = ( xHigh + xLow) * .50 ;

Create a series?

What don't I understand?

THANKING YOU IN ADVANCE

[zeller4]

MidPoint

TRO

I'm wondering if the definition is

MidPoint = (H+L)/2; found in the following thread.

Click here to view post by ckryza

Also, I'm doing a search on "waist" or "candlewaist". I seem to remember Alex helping out with code for that study...

Hope this helps.
kz

[buzzhorton]

Re: MidPoint

Usually, computers multiply faster than they divide .

That's why I have midpoint = ( h + l ) * .50

Same as (h + l) / 2, just faster.

I see the "waist", but I haven't studied that.

Originally posted by zeller4
TRO

I'm wondering if the definition is

MidPoint = (H+L)/2; found in the following thread.

Click here to view post by ckryza

Also, I'm doing a search on "waist" or "candlewaist". I seem to remember Alex helping out with code for that study...

Hope this helps.
kz

[zeller4]

Good to note about multiplying...

I was mainly pointing out MidPoint with Capital "P" if Case Sensitive is a potential problem.

kz

[buzzhorton]

I finally fiquered out how to do what I wanted to do.

I wrote the TRO SM MIDDLE study that uses series and calculates the midpoint.

It's still not clear to me.

Whoever created JAVA is a SADIST!

It's not intuitive and it is CASE SENSITIVE... WHAT WERE THEY THINKING?

Such a waste of time.

Originally posted by zeller4
Good to note about multiplying...

I was mainly pointing out MidPoint with Capital "P" if Case Sensitive is a potential problem.

I know you'll get to the bottom of it...

kz

[eSignal_JasonK]

Hello Avery,

Originally posted by buzzhorton
Alexis or anyone else:

I just can't seem to figure out SERIES data.

Everytime I think I "get" it, I run into another problem.

I must have a MENTAL BLOCK.

I want to be able to define xOPEN, xHIGH, xMIDPOINT, xLOW, and xCLOSE so I can reference values in this manner:

xMIDPOINT(-1) : previous day's midpoint

xMIDPOINT(0) : current day's midpoint.

var xInit   = false;
var xMiddle = null;

var xOpen   = null;
var xHigh   = null;
var xLow    = null;
var xClose  = null;

function main( ) {


    if(xInit==false){         


         xOpen   =  open( inv("D") ) ;

         
         xHigh   =  high( inv("D") ) ;

         xLow    =  low( inv("D") ) ;

         xClose  =  close( inv("D") ) ;

         xInit=true;

    } // xInit 


var zOpen   = xOpen.getValue(0) ;

var zClose1 = xClose.getValue(-1) ;

var zHigh   = xHigh.getValue(-1) ;

var zLow    = xLow.getValue(-1) ;

var zMid1   = rnd( ((zHigh + zLow) * .50) , 2 )   ;
var zGap    = rnd( (zOpen - zClose1) , 2) ;


debugPrint( "zMid1  xInit   : " + zMid1  + "\n" ); 
debugPrint( "zGap  xInit   : " + zGap + "\n" ); 

return ; // main

}


//==rnd will round to N digits.
function rnd(value, N) {
    var n;
    var mult=1;
    for(n=0;n<N;n++) mult*=10;
    value*=mult;
    return Math.round( value,N)/mult;
} 

From what I have read, that should create a series.

It works.

I am still baffled.

It is just not INTUITIVE.

Sometimes, I can create a series that works and sometimes what I code just doesn't work.

Why doesn't xMidpoint = ( xHigh + xLow) * .50 ;

Create a series?

What don't I understand?

THANKING YOU IN ADVANCE

To create a custom series you have to run it through efsInternal(). When you use variables that contain series objects in a math equation, the EFS2 engine automaticlly retrieves the current values from those series so it can return a number as a result. It was designed this way to make things easier on the novice users.

xMidpoint = (xHigh.getValue(0) + xLow.getValue(0)) * .50;

is the same as

xMidpoint = ( xHigh + xLow) * .50 ;

which returns a number.

To create the xMidpoint series do this

function main() {
    ....
    if (xMidpoint == null) xMidpoint = efsInternal("calcMidpoint", xHigh, xLow);

    ....
}

function calcMidpoint(xH, xL) {
    return (xH.getValue(0) + xL.getValue(0)) * .50;
} 

[buzzhorton]

Thanks Jason,

But what I wanted to do was access the previous middle as xMiddle(-1).

I just can't seem to figure it out.

Nothing about this is intuitive... at least not to me.

I can access the data and it's correct.

I just want to use the "x(-1)" type of reference instead of "x.getValue(-1)" ... I AM SO CONFUSED.

Once it finally sinks in, I know I'll have a good laugh.

P.S. The jury is still out on this: "It was designed this way to make things easier on the novice users."

var xInit    = false;
var xMiddle1 = null;

var xMidpoint = null;
var xOpen   = null;
var xHigh   = null;
var xLow    = null;
var xClose  = null;

function preMain() {

    setPlotType(PLOTTYPE_SQUAREWAVE ,0);

    setDefaultBarThickness(2,0);   
}

function main( ) {

    if(xInit==false){         

         xOpen   =  open(   ) ;
         
         xHigh   =  high(   ) ;

         xLow    =  low(   ) ;

         xClose  =  close(   ) ;

         xInit=true;

    } // xInit 
     
if (xMidpoint == null) xMidpoint = efsInternal("calcMidpoint", xHigh, xLow);

// debugPrint( "xMidpoint.getValue(0) : " + xMidpoint.getValue(0)   + "\n" );

xMiddle = rnd( xMidpoint.getValue(0) , 2 )  ;

xMiddle1 = rnd( xMidpoint.getValue(-1) , 2 )  ;

debugPrint( "xMiddle1 : " + xMiddle1   + "\n" );

debugPrint( "xMiddle  : " + xMiddle  + "\n" );

return new Array( getSeries(xMidpoint)  ) ;

}

function calcMidpoint(xH, xL) {
    return (xH.getValue(0) + xL.getValue(0)) * .50;
}

// rnd function - round to iDecimals places
function rnd(value, iDecimals ) {  

value =  value * Math.pow(10, iDecimals);

    return Math.round(value, iDecimals) / Math.pow(10, iDecimals);
} 

[eSignal_JasonK]

Hello Avery,

Originally posted by buzzhorton
Thanks Jason,

But what I wanted to do was access the previous middle as xMiddle(-1).

I just can't seem to figure it out.

Nothing about this is intuitive... at least not to me.

I can access the data and it's correct.

I just want to use the "x(-1)" type of reference instead of "x.getValue(-1)" ... I AM SO CONFUSED.

Once it finally sinks in, I know I'll have a good laugh.

P.S. The jury is still out on this: "It was designed this way to make things easier on the novice users."

var xInit    = false;
var xMiddle1 = null;

var xMidpoint = null;
var xOpen   = null;
var xHigh   = null;
var xLow    = null;
var xClose  = null;

function preMain() {

    setPlotType(PLOTTYPE_SQUAREWAVE ,0);

    setDefaultBarThickness(2,0);   
}

function main( ) {

    if(xInit==false){         

         xOpen   =  open(   ) ;
         
         xHigh   =  high(   ) ;

         xLow    =  low(   ) ;

         xClose  =  close(   ) ;

         xInit=true;

    } // xInit 
     
if (xMidpoint == null) xMidpoint = efsInternal("calcMidpoint", xHigh, xLow);

// debugPrint( "xMidpoint.getValue(0) : " + xMidpoint.getValue(0)   + "\n" );

xMiddle = rnd( xMidpoint.getValue(0) , 2 )  ;

xMiddle1 = rnd( xMidpoint.getValue(-1) , 2 )  ;

debugPrint( "xMiddle1 : " + xMiddle1   + "\n" );

debugPrint( "xMiddle  : " + xMiddle  + "\n" );

return new Array( getSeries(xMidpoint)  ) ;

}

function calcMidpoint(xH, xL) {
    return (xH.getValue(0) + xL.getValue(0)) * .50;
}

// rnd function - round to iDecimals places
function rnd(value, iDecimals ) {  

value =  value * Math.pow(10, iDecimals);

    return Math.round(value, iDecimals) / Math.pow(10, iDecimals);
} 

EFS does not have an "x(-1)" option available. That type of syntax does not exist for a custom series established with efsInternal. The proper way to reference previous values of the xMidpoint series is with the xMidpoint.getValue(-1) method.