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File Name: RefUsage.efs

The function, ref(), is used to refer to previously returned values of a formula's indicator. This example formula demonstrates the usage of ref() for formulas that return only one indicator to the chart.

Formula Parameters:

The formula uses a basic moving average study and outputs information to the Formula Output Window. To view the results, open the output window before applying the formula to a chart from the "Tools" menu.

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EFS Code:
/*******************************Provided By : eSignal. (c) Copyright 2003*******************************//***  syntax: ref(nRelativeOffset, nNumBars)   ***    These examples are based on formulas that return a single value.  For example:        return vValue;            See RefUsage2.efs for examples of formulas that returns an array of values. For example:        return new Array(vValue1, vValue2);        var myRef = ref(-1)     Returns the previous bar's value.    var myRef = ref(-3, 3)  Returns values of bars -3 to -1 bars ago.    var myRef = ref(-1, -3) Returns values of bars -1 to -3 bars ago.        Note:   VERY IMPORTANT!!                When using ref() it is very important that you incorporate some logic into your            code that will ensure that ref() returns a valid result.  See the "BarCntr" logic             below.  If you don't use the BarCntr logic or some other technique, you will get            unfavorable results. **********************************************/var study1 = new MAStudy(10, 0, "Close", MAStudy.Simple); function preMain() {    setPriceStudy(true);}var BarCntr = 0;function main() {    var vMA1 = study1.getValue(MAStudy.MA);        if (getBarState() == BARSTATE_NEWBAR) {        BarCntr += 1;    }/***  BarCntr logic  ***/    if (BarCntr > 10) {     // We're using 10 because our MAStudy requires a minimum of 10 bars.    var myRef = ref(-1);    if (myRef == null) return;    //var myRef = ref(-3, 3);    //var myRef = ref(-1, -3);    }    // Open the Formula Output Window from the tools menu to view the values of myRef.    if (BarCntr > 10) {        debugPrintln("Bar Index: " + getCurrentBarIndex() + "    myRef= " + myRef);    }        return vMA1;}