RWInterval< T > Class Template Reference

A class template for describing an interval of values. More...

#include <rw/analytics/interval.h>

Public Types
enum	Type { open, closed, openClosed, closedOpen }

Public Member Functions
	RWInterval ()
	RWInterval (T a, T b, Type t)
	RWInterval (const RWInterval< T > &i)
bool	contains (T x)
T	lowerBound () const
RWInterval< T > &	operator= (const RWInterval< T > &rhs)
void	setBound (T x)
void	setBounds (T a, T b)
void	setType (Type t)
Type	type () const
T	upperBound () const

Related Functions
(Note that these are not member functions.)
template<class T >
bool	operator== (const RWInterval< T > &lhs, const RWInterval< T > &rhs)

Detailed Description

template<class T>
class RWInterval< T >

RWInterval<T> is a general-purpose class for describing an interval of values. The values in the interval are of type T. An interval may be considered a set of contiguous values where the interval endpoints are either included or excluded from the set. If an interval's endpoints are excluded, it is said to be open; if the endpoints are included, the interval is said to be closed.

In Linear Algebra Module, the class RWInterval<T> is used to describe confidence intervals for regression predictions and parameter estimates.

Synopsis

#include <rw/analytics/interval.h>

RWInterval<double> ci( -1.031, 2.045, RWInterval<double>::closed);

Example

The following example prints the linear regression prediction interval for the first pattern in the predictor matrix at a confidence level of 99 percent.

#include <rw/analytics/linregress.h>
#include <rw/analytics/interval.h>

int main() {
 RWGenMat<double> predictorMatrix =
                  "5x2 [1.2 2.1 8 7 3 3.2 6.4 4.6 2 2.3]";
 RWMathVec<double> observationVector = "[2.5 3.7 1.4 2.3 5.6]";

 RWLinearRegression lr(predictorMatrix, observationVector);
 RWMathVec<double> firstPredPattern = predictorMatrix(0,RWAll);
 RWInterval<double> interval =
                  lr.predictionInterval(firstPredPattern, 0.01);

 cout << "Interval lower bound: " << interval.lowerBound() <<
         endl;
 cout << "Interval upper bound: " << interval.upperBound() <<
         endl;
 return 0;
}

Member Enumeration Documentation

template<class T>

enum RWInterval::Type

If the left endpoint is a and the right endpoint is b, and \(a \leq b\)

then the values of the Type enumeration have the following meanings:

Enumerator
open	(a,b)
closed	[a,b]
openClosed	(a,b]
closedOpen	[a,b)

Constructor & Destructor Documentation

template<class T>

RWInterval< T >::RWInterval ( )

inline

Constructs an empty interval.

template<class T>

RWInterval< T >::RWInterval ( T  a, T  b, Type  t  )

inline

Constructs an interval of type t with endpoints a and b.

template<class T>

RWInterval< T >::RWInterval ( const RWInterval< T > &  i )

inline

Constructs a copy of i.

Member Function Documentation

template<class T>

bool RWInterval< T >::contains ( T  x )

inline

Returns true if the interval contains x, otherwise returns false.

template<class T>

T RWInterval< T >::lowerBound ( ) const

inline

Returns the interval's lower bound.

template<class T>

RWInterval<T>& RWInterval< T >::operator= ( const RWInterval< T > &  rhs )

inline

Sets self equal to rhs.

template<class T>

void RWInterval< T >::setBound ( T  x )

inline

Sets the interval's upper bound to x if x is greater than the current upper bound. Otherwise, sets the lower bound to x.

template<class T>

void RWInterval< T >::setBounds ( T  a, T  b  )

inline

Sets the interval's lower bound to the smaller of the two values and the upper bound to the larger of the two values.

template<class T>

void RWInterval< T >::setType ( Type  t )

inline

Sets the interval's type to t.

template<class T>

Type RWInterval< T >::type ( ) const

inline

Returns the interval's type.

template<class T>

T RWInterval< T >::upperBound ( ) const

inline

Returns the interval's upper bound.

Friends And Related Function Documentation

template<class T >

bool operator== ( const RWInterval< T > &  lhs, const RWInterval< T > &  rhs  )

related

Returns true if the intervals have the same endpoints and type.