# Moving Averages

ICE Data Services -

sma(), ema(), smma(), wma(), vwma() Built-in Study Functions

A Moving Average is an indicator that shows the average value of a security's price over a period of time. When calculating a moving average, a mathematical analysis of the security's average value over a predetermined time period is made. As the security's price changes, its average price moves up or down.

Syntax
sma(  nLength [, Series | sym() | inv() ][, nBarIndex ] )
ema(  nLength [, Series | sym() | inv() ][, nBarIndex ] )
smma(  nLength [, Series | sym() | inv() ][, nBarIndex ] )
wma(  nLength [, Series | sym() | inv() ][, nBarIndex ] )
vwma( nLength [, Series | sym() | inv() ][, nBarIndex ] )

Parameters
Parameter: Description: Default:
nLength Required. Number of periods to use for calculation.

n/a Series or
sym() or
inv()
[Optional]   Series Object or function of sym() or inv() to determine symbol/interval source for the study.

Base sym/inv nBarIndex [Optional]  Bar index of series to retrieve.

n/a

Return Value(s)

Returns a Series Object when nBarIndex is not specified.

Returns a single value when nBarIndex is specified.

Notes
Functions sma(), ema(), wma(), vwma() are only available in versions 7.9 or later.
Function smma() is only available in versions 12.1 or later.

Code Examples
Single Line Indicator:
 `function main() { return new Array(sma(10), ema(10), `
smma(10), wma(10), vwma(10));}
Single Line Study-on-Study Indicator:
 `function main() { return new Array(sma(10, hl2()), ema(10, hl2()), smma(10, hl2()), wma(10, hl2()), vwma(10, hl2()));}`

Retrieve single values:
 ``function main() { var nValue_0 = ema(10, 0); // Current Bar Index var nValue_1 = ema(10, -1); // Prior Bar Index return new Array(nValue_0, nValue_1);}``

Initialize Series Objects:
 ``//global Series Object variablesvar xStudy1 = null;var xStudy2 = null;var xStudy3 = null;function main() { if (xStudy1 == null) xStudy1 = sma(10); if (xStudy2 == null) xStudy2 = ema(10); if (xStudy3 == null) xStudy3 = wma(10); // retrieve single values for conditional statements var nValue1_0 = xStudy1.getValue(0); // Current Bar Index value var nValue2_0 = xStudy2.getValue(0); // Current Bar Index value var nValue3_0 = xStudy3.getValue(0); // Current Bar Index value var nValue1_1 = xStudy1.getValue(-1); // Prior Bar Index value // Plot Current Bar Index Value return new Array(nValue1_0, nValue2_0, nValue3_0); }``

Initialize a Series Object based on an external interval:
 ``// global Series Object variablesvar xStudy1 = null;var xStudy2 = null;var xStudy3 = null;var bInit = false; // Initialization flagfunction main() { if (bInit == false) { xStudy1 = sma(10, inv(20)); // 20-min interval xStudy2 = ema(10, inv(20)); // 20-min interval xStudy3 = wma(10, inv(20)); // 20-min interval bInit = true; } // retrieve single values for conditional statements var nValue1_0 = xStudy1.getValue(0); // Current Bar Index value var nValue1_1 = xStudy1.getValue(-1); // Prior Bar Index value // Synchronized Series plot return new Array(getSeries(xStudy1), getSeries(xStudy2), getSeries(xStudy3) ); }``

Initialize a Series Object based on an external symbol and interval:
 ``// global Series Object variablesvar xStudy1 = null;var xStudy2 = null;var xStudy3 = null;var bInit = false; // Initialization flagfunction main() { if (bInit == false) { xStudy1 = sma(10, sym("IBM,20")); // IBM 20-min interval xStudy2 = ema(1``0, sym("IBM,20")``); // ``IBM ``20-min interval xStudy3 = wma(1``0, sym("IBM,20")``); // ``IBM ``20-min interval bInit = true; } // retrieve single values for conditional statements var nValue1_0 = xStudy1.getValue(0); // Current Bar Index value var nValue1_1 = xStudy1.getValue(-1); // Prior Bar Index value // Synchronized Series plot return new Array(getSeries(xStudy1), getSeries(xStudy2), getSeries(xStudy3) ); }``