Summary:
This indicator script measures the current closing price in relation to the high and low of the past specified number of periods.

Range:
-100 To 0

Developer:
Larry Williams

Interpretation:
1. Overbought: When the underlying symbol is moving upwards, but the indicator script is approaching its upper bound, the underlying symbol is likely to reverse direction and move downwards.
2. Oversold: When the underlying symbol is moving downwards, but the indicator script is approaching its lower bound, the underlying symbol is likely to reverse direction and move upwards.

                    
#region Namespaces using System; #endregion namespace ScriptCode { /// <summary> /// Indicator scripts are used for calculating a series of numerical values. /// /// This script can be used in several ways: /// (1) It can be used on a chart. /// (2) It can be used from another script. /// (3) It can be used as a script column in a watchlist. /// </summary> public partial class MyIndicator : IndicatorScriptBase // NEVER CHANGE THE CLASS NAME { #region Variables // Use for the underlying symbol index on which to calculate the indicator script. private int _symbolIndex; // Use for the number of periods to include in the indicator script calculation. private int _periods; #endregion #region OnInitialize /// <summary> /// This function accepts the user parameters for the script and is called when a new indicator instance is created. /// One of the parameters accepted by it must be that of a symbol or another script that is /// based on a symbol (drawing, indicator, pattern or signal). This symbol will be used as the underlying symbol for the indicator. /// /// The parameter values can be specified from the user interface (UI) or from another script, depending on usage. /// </summary> /// -------------------------------------------------------------------------------------------------- /// PLEASE USE THE SCRIPT WIZARD (CTRL+W) TO ADD, EDIT AND REMOVE THE SCRIPT PARAMETERS /// -------------------------------------------------------------------------------------------------- /// YOU MUST SET A PARAM TAG FOR EACH PARAMETER ACCEPTED BY THIS FUNCTION. /// ALL PARAM TAGS SHOULD BE SET IN THE 'OnInitialize' REGION, RIGHT ABOVE THE 'OnInitialize' FUNCTION. /// THE ORDER OF THE TAGS MUST MATCH THE ORDER OF THE ACTUAL PARAMETERS. /// REQUIRED ATTRIBUTES: /// (1) name: The exact parameter name. /// (2) type: The type of data to collect from the user: /// Set to "Integer" when the data type is 'int' /// Set to "IntegerArray" when the data type is 'int[]' /// Set to "DateTime" when the data type is 'long' /// Set to "DateTimeArray" when the data type is 'long[]' /// Set to "Boolean" when the data type is 'bool' /// Set to "BooleanArray" when the data type is 'bool[]' /// Set to "Double" when the data type is 'double' /// Set to "DoubleArray" when the data type is 'double[]' /// Set to "String" when the data type is 'string' /// Set to "StringArray" when the data type is 'string[]' /// Set to "Indicator" when the data type is 'Indicator' /// Set to "Pattern" when the data type is 'Pattern' /// Set to "Signal" when the data type is 'Signal' /// Set to "Drawing" when the data type is 'Drawing' /// Set to "Symbol" when the data type is 'int' representing a symbol index. /// OPTIONAL ATTRIBUTES: /// (3) default: The default parameter value is only valid when the type is Integer, Boolean, Double or String. /// (4) min: The minimum parameter value is only valid when the type is Integer or Double. /// (5) max: The maximum parameter value is only valid when the type is Integer or Double. /// EXAMPLE: <param name="" type="" default="" min="" max="">Enter the parameter description here.</param> /// -------------------------------------------------------------------------------------------------- /// <param name="symbolIndex" type="Symbol" default="">Use for the underlying symbol index on which to calculate the indicator script.</param> /// <param name="periods" type="Integer" default="14" min="1">Use for the number of periods to include in the indicator script calculation.</param> public void OnInitialize( int symbolIndex, int periods) { // Set the symbol index. _symbolIndex = symbolIndex; // Set the number of periods. _periods = periods; } #endregion #region OnBarUpdate /// <summary> /// This function is used for calculating the indicator value for the latest bar (see the Indicator functions). /// </summary> /// <returns>The indicator value for the latest bar.</returns> public override double OnBarUpdate() { // Use for holding the highest and lowest numbers so far. double highest = 0; double lowest = double.MaxValue; // Iterate over the specified number of periods. for (int i = _periods - 1; i >= 0; i--) { // Check whether the highest number should be updated. if (highest < BarHigh(_symbolIndex, i)) // Update the highest number. highest = BarHigh(_symbolIndex, i); // Check whether the lowest number should be updated. if (lowest > BarLow(_symbolIndex, i)) // Update the lowest number. lowest = BarLow(_symbolIndex, i); } // Check whether the highest minus the lowest is valid. if ((highest - lowest) != 0) // Return the latest Williams %R value. return 100 * (BarClose(_symbolIndex, 0) - highest) / (highest - lowest); // Return the previous value since an indicator value can't be calculated. else return this[0]; } #endregion #region OnChartSetup /// <summary> /// This function is used for setting up the indicator on the chart and registering its pens (see the IndicatorRegisterPen function). /// </summary> public override void OnChartSetup() { // Register a pen. IndicatorRegisterPen(0, "Pen", new byte[] { 150, 150, 150, 200}, IQ_DashStyle.SOLID, 2); // Set the indicator in a new chart panel. IndicatorChartSetNewPanel(true); // Set the plot style. IndicatorChartSetPlotStyle(IQ_PlotStyle.BAR_ZERO); // Set the indicator range. IndicatorChartSetRange(-100, 0); // Set the overbought range. IndicatorChartSetColorZone(-30, -30, new byte[] { 175, 25, 25, 200}, new byte[] { 175, 25, 25, 200}, new byte[] { 175, 25, 25, 200}, IQ_DashStyle.SOLID, 2); // Set the oversold range. IndicatorChartSetColorZone(-70, -70, new byte[] { 25, 200, 25, 200}, new byte[] { 25, 200, 25, 200}, new byte[] { 25, 200, 25, 200}, IQ_DashStyle.SOLID, 2); } #endregion #region OnSelectPen /// <summary> /// This function is used for selecting a registered indicator pen with which to color the latest indicator value. /// Call the IndicatorRegisterPen function from the OnChartSetup function in order to register an indicator pen. /// </summary> /// <returns>The indicator pen index to use for coloring the latest indicator value.</returns> public override byte OnSelectPen() { // Color the indicator value with the zero pen. return 0; } #endregion } }

The Algorithmic Trading Software for Hedge Funds and Quants