ref()
ref( nParams )
- nParams: Offsets indicating which historical indicator data points you wish to retrieve.
This is a special function that allows you to retrieve prior values for a built-in study or studies.
Examples:
/*** syntax: ref(nRelativeOffset, nNumBars) ***
//These examples are based on formulas that return multiple values. For example:
//return new Array(vValue1, vValue2);
//See RefUsage.efs for examples of formulas that return a single values. For example:
//return vValue;
var myRef = ref(-1) Returns an array of the previous bar's values:
myRef[0] = vMA1 from -1 bar ago.
myRef[1] = vMA2 from -1 bar ago.
var myRef = ref(-2, 2) Returns a two dimentional array of values for bars -2 to -1 bars ago:
myRef[0][0] = vMA1 from -2 bars ago.
myRef[0][1] = vMA2 from -2 bars ago.
myRef[1][0] = vMA1 from -1 bar ago.
myRef[1][1] = vMA2 from -1 bar ago.
var myRef = ref(-1, -2) Returns a two dimentional array of values for bars -1 to -2 bars ago:
myRef[0][0] = vMA1 from -1 bar ago.
myRef[0][1] = vMA2 from -1 bar ago.
myRef[1][0] = vMA1 from -2 bars ago.
myRef[1][1] = vMA2 from -2 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);
var study2 = new MAStudy(20, 0, "Close", MAStudy.Simple);
function preMain() {
setPriceStudy(true);
}
var BarCntr = 0;
function main() {
var vMA1 = study1.getValue(MAStudy.MA);
var vMA2 = study2.getValue(MAStudy.MA);
if (getBarState() == BARSTATE_NEWBAR) {
BarCntr += 1;
}
/*** BarCntr logic ***/
if (BarCntr > 20) { // We're using 20 because our longest MAStudy requires a minimum of 20 bars.
var myRef = ref(-1);
//var myRef = ref(-2, 2);
//var myRef = ref(-1, -2);
var myValue1 = myRef[0];
var myValue2 = myRef[1];
}
// Open the Formula Output Window from the tools menu to view the values of myRef.
if (BarCntr > 20) {
debugPrintln("Bar Index: " + getCurrentBarIndex() + " myValue1= " + myValue1 + " myValue2= " + myValue2);
}
return new Array(vMA1, vMA2);
}
Example2:
/*** 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);
//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;
}