Relative Strength Index – EFS

rsi() Built-in Study Functions

The Relative Strength Index (RSI) is designed to indicate a market's current strength or weakness depending on where prices close during a given period. It is based on the premise that higher closes indicate strong markets and lower closes indicate weak markets. The RSI is displayed as three lines, the RSI and two moving averages of the RSI. The RSI is calculated by finding the percentage of positive closes (the current close is higher than the previous close) to negative closes (the current close is lower than the previous close).

Syntax

rsi( 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.	Chart's 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

Only available in versions 7.9 or later.

Code Examples

Single Line Indicator:

function main() {
  return rsi(14);
}

Single Line Study-on-Study Indicator:

function main() {
  return rsi(14, hl2());
}

Retrieve single values:

function main() {
  var nValue_0 = rsi(14, 0); // Current Bar Index
  var nValue_1 = rsi(14, -1); // Prior Bar Index
  return new Array(nValue_0, nValue_1);
}

Initialize a Series Object:

var xStudy = null;
function main() {
  if (xStudy == null) {
    xStudy = rsi(14);
  } // retrieve single values for conditional statements
  var nValue_0 = xStudy.getValue(0); // Current Bar Index value
  var nValue_1 = xStudy.getValue(-1); // Prior Bar Index value
  return nValue_0; // Plot Current Bar Index Value
}

Initialize a Series Object based on an external interval:

var xStudy = null;
var bInit = false; // Initialization flag
function main() {
  if (bInit == false) {
    xStudy = rsi(14, inv(20)); // 20-min interval
    bInit = true;
  }
  // retrieve single values for conditional statements
  var nValue_0 = xStudy.getValue(0); // Current Bar Index value
  var nValue_1 = xStudy.getValue(-1); // Prior Bar Index value
  return getSeries(xStudy); // Synchronized Series plot
}

Initialize a Series Object based on an external symbol and interval:

var xStudy = null;
var bInit = false; // Initialization flag
function main() {
  if (bInit == false) {
    xStudy = rsi(14, sym("IBM,20")); // IBM 20-min interval
    bInit = true;
  } // retrieve single values for conditional statements
  var nValue_0 = xStudy.getValue(0); // Current Bar Index value
  var nValue_1 = xStudy.getValue(-1); // Prior Bar Index value
  return getSeries(xStudy); // Synchronized Series plot
}