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                                                   Problem with performance calculation in custom function


2017-02-05 12:54:52

Hello Sir,

I am writing a custom function which returns rate of change from first visible date on the chart but am having error in calculation. I would appreciate if you can point where my mistake is.

This is the srcipt which sets global variable of visible date


Chart chart = Charts.GetSelectedChart();

DateTime startdate = chart.VisibleStartDate;



Function is below

VectorDate vDate = cFunctions.Date;
String temp = Global.GetVariable("Date").ToString();
//DateTime date = DateTime.Parse(temp);
DateTime date = DateTime.Parse(temp, System.Globalization.CultureInfo.InvariantCulture);

double tt = 0;
int i = 0;

for(i=0; i<result.Length; i++)
if(vDate[i] == date){
tt = a[i];
result[i] = 0;

for(i=0; i < result.Length; i++)
if(vDate[i] >= date){
result[i] = ((a[i] - tt)/a[i])*100;

cFunctions.SetForwardAndBackwardBars(0, 0);

I tested this on symbol GDXJ for with start date feb 1 2017 (close = 38.07) and end date feb 3 2017 (close = 39.26)

so the performance on feb 3 is 3.125 but
my function returns 3.03

I can't figure out why I am seeing this discrepancy

Thank you

2017-02-05 14:58:19


Found the problem !!

result[i] = ((a[i] - tt)/tt)*100; instead of

result[i] = ((a[i] - tt)/a[i])*100;

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