public class CategoricalScale : IEnumerable

Public Class CategoricalScale
	Implements IEnumerable

public ref class CategoricalScale : IEnumerable

type CategoricalScale =  
    class
        interface IEnumerable
    end

The CategoricalScale type exposes the following members.

	Name	Description
	CategoricalScale(ICollection)	Constructs a categorical scale from an ICollection.
	CategoricalScale(Type)	Constructs a factor from an enumeration type.
	CategoricalScale(SortOrder)	Constructs a new categorical scale.
	CategoricalScale(Type, SortOrder)	Constructs a factor from an enumeration type.
	CategoricalScale(ICollection, String, SortOrder)	Constructs a categorical scale from an ICollection.

	Name	Description
	Count	Gets the number of levels in this CategoricalScale.
	IsOrdered	Gets whether the categorical scale is ordered or unordered.
	Item	Gets the level corresponding to the specified level index. In C#, this property is the indexer for the DateTimeScale class.
	SortOrder	Gets a value that indicates how the levels in the scale are sorted.

	Name	Description
	Equals	Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
	Finalize	Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
	GetCaption	Gets a textual representation of the level at the specified index.
	GetCaptions	Gets an array containing the captions of the levels in this CategoricalScale.
	GetComparer	Gets an IComparer object that can be used to compare the levels of this CategoricalScale.
	GetEnumerator	Returns an IEnumerator object that can be used to iterate through the levels of the CategoricalScale.
	GetHashCode	Serves as a hash function for a particular type. (Inherited from Object.)
	GetLevelIndex	Gets the index of the specified level in this CategoricalScale.
	GetLevels	Gets an array containing the levels of this CategoricalScale.
	GetType	Gets the Type of the current instance. (Inherited from Object.)
	Map(Object)	Gets the index of the specified level in this CategoricalScale.
	Map(Object)	Returns an array of indexes corresponding to the
	MemberwiseClone	Creates a shallow copy of the current Object. (Inherited from Object.)
	ToString	Returns a string that represents the current object. (Inherited from Object.)

Use the CategoricalScale class to represent the possible values for a categorical variable. The unique values are called levels. Every level is assigned an index, ranging from 0 to the number of distinct values minus 1.

The Map(Object) method finds the level index corresponding to an object.

Using a CategoricalScale, a categorical variable can be transformed into a numerical variable by replacing the level value by its level index. However, care should be taken that no new meaning is assigned to the numerical value of the level index. A variable that represents color using the categories 'red', 'green' and 'blue' can be converted into a numerical variable with possible values 0, 1, and 2. However, it is completely meaningless to talk about the mean or variance of this variable.

Several derived classes provide functionality tailored to specific kinds of data. These classes extend the Map(Object) methods:

CategoricalScale objects are used by CategoricalVariable objects to map levels to numerical values (level indexes).

Numerical Libraries

Reference