net.sf.tweety.math.term

Class Logarithm

java.lang.Object

net.sf.tweety.math.term.Term

net.sf.tweety.math.term.FunctionalTerm

net.sf.tweety.math.term.Logarithm

public class Logarithm
extends FunctionalTerm

Instances of this class represent application of the logarithm function on some term.

Author:

Matthias Thimm

Constructor Summary

Constructors

Constructor and Description
Logarithm(Term term) Creates a new logarithm term for the give inner term.

Method Summary

Modifier and Type	Method and Description
Term	derive(Variable v) Differentiates the term with respect to the given variable.
boolean	isContinuous(Variable v) Checks whether this term is continuous in v.
Term	replaceTerm(Term toSubstitute, Term substitution) Replaces each occurrence of "toSubstitute" by "substitution" and return the new term.
Term	simplify() Simplifies this term in an equivalent way: - Replaces products that contain a zero by the constant zero - Removes a term one from products - Removes a term zero from sums - Aggregates constants in sums, products, and minimums - Evaluates functional terms on constants - Simplifies fractions where possible.
java.lang.String	toString()
Constant	value() Computes the actual value of this term if it contains no variables.

Methods inherited from class net.sf.tweety.math.term.FunctionalTerm

collapseAssociativeOperations, expandAssociativeOperations, getAbsoluteValues, getMaximums, getMinimums, getProducts, getTerm, getVariables, isInteger, toLinearForm

Methods inherited from class net.sf.tweety.math.term.Term

add, doubleValue, evaluateMatrix, evaluateVector, evaluateVector, isContinuous, isLinear, min, minus, mult, replaceAllTerms, replaceAllTerms

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

Logarithm

public Logarithm(Term term)

Creates a new logarithm term for the give inner term.

Parameters:

term - a term

Method Detail

replaceTerm

public Term replaceTerm(Term toSubstitute,
                        Term substitution)

Description copied from class: Term

Replaces each occurrence of "toSubstitute" by "substitution" and return the new term.

Specified by:

replaceTerm in class FunctionalTerm

Parameters:

toSubstitute - the term to be substituted

substitution - the new term

Returns:

this term where "toSubstitute" is replaced by "substitution"

toString

public java.lang.String toString()

Specified by:

toString in class FunctionalTerm

derive

public Term derive(Variable v)
            throws NonDifferentiableException

Description copied from class: Term

Differentiates the term with respect to the given variable.

Specified by:

derive in class Term

Parameters:

v - a variable.

Returns:

the derivation of this term wrt. the given variable.

Throws:

NonDifferentiableException - if the term cannot be differentiated.

simplify

public Term simplify()

Description copied from class: Term

Simplifies this term in an equivalent way:
- Replaces products that contain a zero by the constant zero
- Removes a term one from products
- Removes a term zero from sums
- Aggregates constants in sums, products, and minimums
- Evaluates functional terms on constants
- Simplifies fractions where possible.

Specified by:

simplify in class Term

Returns:

the simplified term.

isContinuous

public boolean isContinuous(Variable v)

Description copied from class: Term

Checks whether this term is continuous in v.

Specified by:

isContinuous in class Term

Returns:

"true" iff this term is continuous in v.

value

public Constant value()
               throws java.lang.IllegalArgumentException

Description copied from class: Term

Computes the actual value of this term if it contains no variables.

Specified by:

value in class FunctionalTerm

Returns:

the value of this term, either a float or an integer.

Throws:

java.lang.IllegalArgumentException - if this term contains at least on variable.