loading string return as an array

[tedsmith]

How do I load this string return as a multi-element array?

vRSI = null;

function main() {
    // RSI
    if (vRSI == null) vRSI = new RSIStudy(8, "Close");

    //var aryRSI = vRSI.getValue(RSIStudy.RSI, 0, -2);  // loads as a single variable, not an array
    var aryRSI = [vRSI.getValue(RSIStudy.RSI, 0, -2)];  // loads as a one element array
    debugPrint ( "aryRSI = " + aryRSI + "\n");
    debugPrint ( "\naryRSI[0] = " + aryRSI[0] + "\n");

} 

like the following does:

var aryClose = getValue("Close", 0, -2); // [0] is close(), [1] is close(-1), etc. 

Thanks,
-Ted.

[Doji3333]

Please explain in more detail

Ted,

What, exactly, are you trying to accomplish??

Do you want to build an array of the RSI data??

or do you want to build an array of the STRINGS??

And how many of the data items are you trying to store?

B

[tedsmith]

B,
I would like to populate an ARRAY just like this command does:
var aryClose = getValue("Close", 0, -2);

The 'getValue("Close", 0, -2)' command appears to automatically create an ARRAY 'aryClose' of the size returned. Size being extracted from the third parameter, -2, passed to getValue. I can access aryClose[0]. A debugPrint of aryClose shows all requested values.

However, the 'var aryRSI = vRSI.getValue(RSIStudy.RSI, 0, -2);' command appears to return a STRING datatype instead of an ARRAY. I cannot access aryRSI[0], while a printDebug of aryRSI shows all requested values in comma delimited format. It seems that the proper values are returned, just not populated in an ARRAY datatype.

Is there a way to get the RSI getValue command to autocreate and populate an ARRAY like the Close getValue command does?

Thanks,
-Ted.

[gspiker]

Ted,

Make sure you are doing a check for a null return before you try to access any element of the array:


var aryRSI = vRSI.getValue(RSIStudy.RSI, 0, -2);
if (aryRSI == null)
return;
debugPrintln("aryRSI[0] = " aryRSI[0]);

Garth

[gspiker]

Ted,

To clarify, RSI() will return null until there is enough data available to honor the requested length. If you don't do the null check you will get an error on execution when there isn't enough data to fulfill the RSI request.

I'm guessing that is your problem, since you don't state why you can't access it (ie: what error you might be seeing).

Garth

[tedsmith]

Garth,
That did it.
(What a forehead slapper!)

This EFS was just a test to resolve my issue. The error was 'TypeError: aryRSI has no properties.'.

Sorry for the hassle. I'll try to be clearer with the initial post next time.

Thanks,
-Ted.

for posterity... the resolution was:

var vBarCount   = 0;
var vRSI = null;

var fp01 = new FunctionParameter("vRSILength", FunctionParameter.NUMBER);
    fp01.setName("RSI Length");
    fp01.setDefault(8);  

var fp02 = new FunctionParameter("vRSISource", FunctionParameter.STRING);
    fp02.setName("RSISource");
    fp02.addOption("Close");
    fp02.addOption("High");
    fp02.addOption("Low");
    fp02.addOption("Open");
    fp02.addOption("HL/2");
    fp02.addOption("HLC/3");
    fp02.addOption("OHLC/4");
    fp02.setDefault("Close");

var fp03 = new FunctionParameter("vRSIHistoryLength", FunctionParameter.NUMBER);
    fp03.setName("RSI History Length");
    fp03.setUpperLimit(1);
    fp03.setDefault(2);  


function main(vRSILength, vRSISource, vRSIHistoryLength) {

    // BarCount
    if ( getBarState() == BARSTATE_NEWBAR ) vBarCount += 1;

    // RSI
    if (vRSI == null) vRSI = new RSIStudy(vRSILength, vRSISource);

    // Load an array of RSI history on each tick, when valid values are available
    if (vBarCount >= vRSILength + vRSIHistoryLength) {
        var aryRSI = vRSI.getValue(RSIStudy.RSI, 0, -vRSIHistoryLength);
        // aryRSI[0] is current value, aryRSI[1] is last value, etc.
        debugPrint ( "aryRSI = " + aryRSI + "\n");
        debugPrint ( "\naryRSI[0] = " + aryRSI[0] + "\n");
    }

}