eSignal EFS

[tttay]

Hi,

In determining the high price for the preceeding trading day in order to compute pivot points for the current day, the PivotPoint.efs supplied by eSignal uses the following functions:
xHigh = high(inv("D"));
vHigh = xHigh.getValue(-1);

In your EFS KnowledgeBase, http://kb.esignal.com/display/2/inde...98504614830017 (descriptions for inv() function), the example given to determine the high price is as follows:
var myVar = high( -1, inv("D") );

I tried out both, and I obtained different values. I would get the same values if I use a different offset
var myVar = high(0, inv("D") );

May I know what cause the differences? Also, in terms of execution efficiency, which one is preferred?

[waynecd]

Hi tttay,

They work as expected on my end.

xHigh.getValue(0) is the same as high( 0, inv("D") )

and

xHigh.getValue(-1) is the same as high( -1, inv("D") )

Try the script below to verify.

For performance try the different combinations using the "Tools-EFS-Performance Monitor" from the main toolbar in eSignal.

function main(){
    xHigh = high(inv("D"));
    vHigh_0 = xHigh.getValue(0);
    var myVar_0 = high( 0, inv("D") );
    vHigh_1 = xHigh.getValue(-1);
    var myVar_1 = high( -1, inv("D") );
    debugPrintln(xHigh+", "+vHigh_0+", "+myVar_0+", "+vHigh_1+", "+myVar_1);
}
/*
xHigh returns a series but if used in debugPrintln(xHigh) it returns the high for bar 0
vHigh_0 returns the high for bar 0
myVar_0 returns the high for bar 0
vHigh_1  returns the high for bar -1
myVar_1   returns the high for bar -1

debugPrint output follows:

xHigh  , vHigh_0, myVar_0, vHigh_1, myVar_1
1105.75, 1105.75, 1105.75, 1115.75, 1115.75
1105.75, 1105.75, 1105.75, 1115.75, 1115.75
1105.75, 1105.75, 1105.75, 1115.75, 1115.75
1105.75, 1105.75, 1105.75, 1115.75, 1115.75
1105.75, 1105.75, 1105.75, 1115.75, 1115.75
1105.75, 1105.75, 1105.75, 1115.75, 1115.75
1105.75, 1105.75, 1105.75, 1115.75, 1115.75
1105.75, 1105.75, 1105.75, 1115.75, 1115.75
*/ 

Wayne

[tttay]

Thanks. I'll check my codes again.

[neoikon]

Perhaps this study will do what you want.

http://neotoolbox.com/blog/post/2009/04/13/EFS-Daily-Pivot-Levels.aspx