org.matheclipse.core.reflection.system

Class Numerator

java.lang.Object

org.matheclipse.core.eval.interfaces.AbstractEvaluator

org.matheclipse.core.reflection.system.Numerator

All Implemented Interfaces:

IFunctionEvaluator, IEvaluator

public class Numerator
extends AbstractEvaluator

Get the numerator part of an expression See Wikipedia: Fraction (mathematics)

See Also:

Denominator

Constructor Summary

Constructors

Constructor and Description
Numerator()

Method Summary

Modifier and Type	Method and Description
IExpr	evaluate(IAST ast, EvalEngine engine) Symbolic evaluation of a function.
static IExpr	getTrigForm(IAST function, boolean trig) Get the "numerator form" of the given function.
void	setUp(ISymbol symbol) Evaluate built-in rules and define Attributes for a function.

Methods inherited from class org.matheclipse.core.eval.interfaces.AbstractEvaluator

numericEval

Methods inherited from class java.lang.Object

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

Constructor Detail

Numerator

public Numerator()

Method Detail

evaluate

public IExpr evaluate(IAST ast,
                      EvalEngine engine)

Description copied from class: AbstractEvaluator

Symbolic evaluation of a function. ast.get(0) (or alternatively ast.head()) contains the head (i.e. the function symbol) of this abstract syntax tree (AST).
From ast.arg1() to ast.get(n) the ast contains the first to n-th argument of the function (alternatively you get the first to fifth argument with the methods arg1(), arg2(),... arg5()).
If necessary use the methods from the Validate class to check the number or types of arguments in the evaluate method.
Note: if the symbolic evaluation isn't possible or no result is found the evaluate method returns with a null value without throwing an exception!

Specified by:

evaluate in interface IFunctionEvaluator

Specified by:

evaluate in class AbstractEvaluator

Parameters:

ast - the abstract syntax tree (AST) which should be evaluated

engine - the users current evaluation engine

Returns:

the evaluated object or null, if evaluation isn't possible

See Also:

Validate, IExpr.head(), IAST.arg1(), IAST.arg2(), IAST.arg3()

setUp

public void setUp(ISymbol symbol)

Description copied from class: AbstractEvaluator

Evaluate built-in rules and define Attributes for a function.

Specified by:

setUp in interface IEvaluator

Overrides:

setUp in class AbstractEvaluator

Parameters:

symbol - the symbol which should be set up

getTrigForm

public static IExpr getTrigForm(IAST function,
                                boolean trig)

Get the "numerator form" of the given function. Example: Csc[x] gives Sin[x].

Parameters:

function - the function which should be transformed to "denominator form" determine the denominator by splitting up functions like Tan[9,Cot[], Csc[],...

Returns: