org.matheclipse.core.expression

Class Symbol

java.lang.Object

org.matheclipse.core.expression.ExprImpl

org.matheclipse.core.expression.Symbol

All Implemented Interfaces:

edu.jas.structure.AbelianGroupElem<IExpr>, edu.jas.structure.Element<IExpr>, edu.jas.structure.GcdRingElem<IExpr>, edu.jas.structure.MonoidElem<IExpr>, edu.jas.structure.RingElem<IExpr>, java.io.Serializable, java.lang.Comparable<IExpr>, org.apache.commons.math4.FieldElement<IExpr>, IExpr, ISymbol

Direct Known Subclasses:

MethodSymbol

public class Symbol
extends ExprImpl
implements ISymbol, java.io.Serializable

Implements Symbols for function, constant and variable names

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from interface org.matheclipse.core.interfaces.ISymbol

ISymbol.RuleType

Field Summary

Fields

Modifier and Type	Field and Description
protected static org.matheclipse.core.expression.Symbol.DummyEvaluator	DUMMY_EVALUATOR

Fields inherited from interface org.matheclipse.core.interfaces.ISymbol

CONSOLE_OUTPUT, CONSTANT, DELAYED_RULE_EVALUATION, FLAT, FLATORDERLESS, HOLDALL, HOLDFIRST, HOLDREST, LISTABLE, NHOLDALL, NHOLDFIRST, NHOLDREST, NOATTRIBUTE, NUMERICFUNCTION, ONEIDENTITY, ORDERLESS, PACKAGE_LOADED

Fields inherited from interface org.matheclipse.core.interfaces.IExpr

ASTID, BLANKID, COMPLEXID, DOUBLECOMPLEXID, DOUBLEID, FRACTIONID, INTEGERID, METHODSYMBOLID, PATTERNID, STRINGID, SYMBOLID

Constructor Summary

Constructors

Constructor and Description
Symbol(java.lang.String symbolName)
Symbol(java.lang.String symbolName, IEvaluator evaluator)

Method Summary

Modifier and Type	Method and Description
<T> T	accept(IVisitor<T> visitor) Accept a visitor with return type T
boolean	accept(IVisitorBoolean visitor) Accept a visitor with return type boolean
int	accept(IVisitorInt visitor) Accept a visitor with return type int
long	accept(IVisitorLong visitor) Accept a visitor with return type long
IExpr	apply(IExpr... expressions)
void	clear(EvalEngine engine) Clear the associated rules for this symbol
void	clearAll(EvalEngine engine) Clear all associated rules and attributes for this symbol
int	compareTo(IExpr expr) Compares this expression with the specified expression for order.
boolean	containsRules() Check if ths symbol contains a "DownRule" or "UpRule"
void	createRulesData(int[] sizes) Create internal rules data structure with precalculated sizes index 0 - number of equal rules in RULES
java.util.List<IAST>	definition() Return a list of the rules associated to this symbol
java.lang.String	definitionToString() Return the rules associated to this symbol in String representation
boolean	equals(java.lang.Object obj) Test if this is equal to b.
org.apache.commons.math4.complex.Complex	evalComplex() Evaluate the expression to a INumber value.
double	evalDouble() Evaluate the expression to a Java double value.
IExpr	evalDownRule(IEvaluationEngine ee, IExpr expression) Evaluate the given expression for the "down value" rules associated with this symbol
INumber	evalNumber() Evaluate the expression to a INumber value.
ISignedNumber	evalSignedNumber() Evaluate the expression to a ISignedNumber value.
IExpr	evaluate(EvalEngine engine) Evaluate an expression
IExpr	evaluateHead(IAST ast, EvalEngine engine)
IExpr	evalUpRule(IEvaluationEngine ee, IExpr expression) Evaluate the given expression for the "up value" rules associated with this symbol
java.lang.String	fullFormString() Return the FullForm() of this expression
IExpr	get() Get the topmost value from the local variable stack
IExpr	getAssignedValue() Get the value which is assigned to the symbol or null, if no value is assigned.
int	getAttributes() Get the Attributes of this symbol (i.e.
IExpr	getDefaultValue() Get the general default value for this symbol (i.e.
IExpr	getDefaultValue(int pos) Get the default value at the arguments position for this symbol (i.e.
IEvaluator	getEvaluator() Get the current evaluator for this symbol
RulesData	getRulesData() Get the rules for initializing the pattern matching rules of this symbol.
java.lang.String	getSymbolName() Get the pure symbol name string
boolean	hasAssignedSymbolValue() Is a (local or global) value assigned for this symbol?
int	hashCode() Hashcode of this Element.
boolean	hasLocalVariableStack() Is a local variable stack created for this symbol ?
ISymbol	head() If this object is an instance of IAST get the first element (offset 0) of the IAST list (i.e. get(0) ).
int	hierarchy() A unique integer ID for the implementation of this expression
java.lang.String	internalFormString(boolean symbolsAsFactoryMethod, int depth) Return the internal Java form of this expression.
java.lang.String	internalJavaString(boolean symbolsAsFactoryMethod, int depth, boolean useOperators) Return the internal Java form of this expression.
java.lang.String	internalScalaString(boolean symbolsAsFactoryMethod, int depth) Return the internal Scala form of this expression.
boolean	isAtom() Test if this expression is an atomic expression (i.e. no AST expression)
boolean	isConstant() Test if this expression is a symbol with attribute Constant.
boolean	isE() Test if this expression equals E (base of the natural logarithm; approximately equal to 2.71828...) in symbolic or numeric mode.
boolean	isFalse() Test if this expression equals the symbol "False"
boolean	isIndeterminate() Test if this expression is representing Indeterminate
boolean	isNegative() Test if this object is a negative signed number.
boolean	isPi() Test if this expression equals Pi (the ratio of a circle's circumference to its diameter, approx. 3.141592...) in symbolic or numeric mode.
boolean	isPolynomial(IAST variables) Test if this expression is a polynomial for the given list of variables.
boolean	isPolynomial(ISymbol variable) Test if this expression is a polynomial for the given variable.
boolean	isPolynomialOfMaxDegree(ISymbol variable, long maxDegree) Test if this expression is a polynomial of maxDegree (i.e.
boolean	isPositive() Test if this object is a positive signed number.
boolean	isString(java.lang.String str) Tests if this symbols name equals the given string
boolean	isSymbolName(java.lang.String name) Returns true, if this symbol has the given name.
boolean	isTrue() Test if this expression equals the symbol True.
boolean	isValue() Returns true, if this symbol or ast expression is bound to a value (i.e. the evaluation returns an assigned value).
boolean	isVariable() Test if this expression is a symbol which doesn't has attribute Constant.
IExpr	mapConstantDouble(INumericFunction<IExpr> function) If this symbol has attribute ISymbol.CONSTANT and the symbol's evaluator is of instance INumericConstant, then apply the constants double value to the given function and return the result, otherwise return F.NIL.
IExpr	negate() Negate this.
void	popLocalVariable() Delete the topmost placeholder from the local variable stack
void	pushLocalVariable() Create a new variable placeholder on the symbols variable stack
void	pushLocalVariable(IExpr expression) Create a new variable placeholder on the symbols variable stack and set the local value
IPatternMatcher	putDownRule(ISymbol.RuleType symbol, boolean equalRule, IExpr leftHandSide, IExpr rightHandSide, boolean packageMode) Associate a new "down value" rule with default priority to this symbol.
IPatternMatcher	putDownRule(ISymbol.RuleType setSymbol, boolean equalRule, IExpr leftHandSide, IExpr rightHandSide, int priority, boolean packageMode) Associate a new rule with the given priority to this symbol.
PatternMatcher	putDownRule(PatternMatcherAndInvoker pmEvaluator) Associate a new rule, which invokes a method, to this symbol.
IPatternMatcher	putUpRule(ISymbol.RuleType symbol, boolean equalRule, IAST leftHandSide, IExpr rightHandSide) Associate a new "up value" rule with default priority to this symbol.
IPatternMatcher	putUpRule(ISymbol.RuleType setSymbol, boolean equalRule, IAST leftHandSide, IExpr rightHandSide, int priority) Associate a new "up value" rule with the given priority to this symbol.
java.lang.Object	readResolve()
void	readRules(java.io.ObjectInputStream stream) Deserialize the rules associated to this object
IExpr[]	reassignSymbolValue(java.util.function.Function<IExpr,IExpr> function, ISymbol functionSymbol) Apply the function to the currently assigned value of the symbol and reassign the result value to the symbol.
void	removeRule(ISymbol.RuleType setSymbol, boolean equalRule, IExpr leftHandSide, boolean packageMode)
void	set(IExpr value) Set the value of the local variable on top of the local variable stack
void	setAttributes(int attributes) Set the Attributes of this symbol (i.e.
void	setDefaultValue(IExpr expr) Set the general default value for this symbol (i.e.
void	setDefaultValue(int pos, IExpr expr) Set the default value at the arguments position for this symbol (i.e.
void	setEvaluator(IEvaluator evaluator) Set the current evaluator which is associated to this symbol
java.lang.String	toString()
IExpr	variables2Slots(java.util.Map<IExpr,IExpr> map, java.util.Collection<IExpr> variableCollector) Convert the variables (i.e. expressions of type ISymbol which aren't constants) in this expression into Slot[] s.
boolean	writeRules(java.io.ObjectOutputStream stream) Serialize the rule definitions associated to this symbol

Methods inherited from class org.matheclipse.core.expression.ExprImpl

$div, $minus, $plus, $times, $up, abs, and, apply, asType, conjugate, copy, dec, divide, egcd, factory, gcd, getAt, inc, inverse, leafCount, leaves, minus, mod, multiply, negative, opposite, optional, or, plus, power, power, remainder, replaceAll, replaceAll, replacePart, replaceRepeated, replaceRepeated, replaceRepeated, replaceSlots, signum, subtract, sum, times, topHead, toScript, toScriptFactory

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.matheclipse.core.interfaces.IExpr

$div, $minus, $plus, $times, $up, and, apply, asType, dec, divide, getAt, getField, ifPresent, inc, inverse, isAllExpanded, isAnd, isArcCos, isArcCosh, isArcSin, isArcSinh, isArcTan, isArcTanh, isAST, isAST, isAST, isAST, isAST, isAST, isAST, isASTSizeGE, isBlank, isComplex, isComplexInfinity, isComplexNumeric, isCondition, isCos, isCosh, isDerivative, isDirectedInfinity, isExpanded, isFlatAST, isFraction, isFree, isFree, isFree, isFreeAST, isFreeAST, isFreeOfPatterns, isFunction, isGEOrdered, isGTOrdered, isInfinity, isInteger, isIntegerResult, isLEOrdered, isList, isListOfLists, isLog, isLTOrdered, isMatrix, isMember, isMember, isMinusOne, isModule, isNegativeInfinity, isNegativeResult, isNonNegativeResult, isNot, isNumber, isNumEqualInteger, isNumEqualRational, isNumeric, isNumericFunction, isNumericMode, isNumIntValue, isOne, isONE, isOr, isOrderlessAST, isPattern, isPatternDefault, isPatternExpr, isPatternSequence, isPlus, isPlusTimesPower, isPositiveResult, isPower, isPresent, isRational, isRationalResult, isRationalValue, isRealResult, isRuleAST, isSame, isSame, isSequence, isSignedNumber, isSin, isSinh, isSlot, isSlotSequence, isSpan, isSymbol, isTan, isTanh, isTimes, isUnit, isVector, isZero, isZERO, leafCount, leaves, minus, mod, multiply, multiply, negative, ofNullable, opposite, optional, or, orElse, orElseGet, orElseThrow, plus, power, power, reciprocal, replaceAll, replaceAll, replacePart, replaceRepeated, replaceRepeated, replaceSlots, signum, subtract, sum, times, timesDistributed, topHead

Methods inherited from interface edu.jas.structure.RingElem

egcd, gcd

Methods inherited from interface edu.jas.structure.AbelianGroupElem

abs

Methods inherited from interface edu.jas.structure.MonoidElem

remainder

Methods inherited from interface edu.jas.structure.Element

copy, factory, toScript, toScriptFactory

Field Detail

DUMMY_EVALUATOR

protected static final org.matheclipse.core.expression.Symbol.DummyEvaluator DUMMY_EVALUATOR

Constructor Detail

Symbol

public Symbol(java.lang.String symbolName)

Symbol

public Symbol(java.lang.String symbolName,
              IEvaluator evaluator)

Method Detail

getRulesData

public RulesData getRulesData()

Get the rules for initializing the pattern matching rules of this symbol.

Specified by:

getRulesData in interface ISymbol

Returns:

null if no rule is defined

reassignSymbolValue

public IExpr[] reassignSymbolValue(java.util.function.Function<IExpr,IExpr> function,
                                   ISymbol functionSymbol)

Apply the function to the currently assigned value of the symbol and reassign the result value to the symbol. Used for functions like AppendTo, Decrement, Increment,...

Specified by:

reassignSymbolValue in interface ISymbol

Parameters:

function - the function which should be applied

functionSymbol - if this method throws a WrongArgumentType exception the symbol will be displayed in the exceptions message

Returns:

an array with the currently assigned value of the symbol and the new calculated value of the symbol or null if the reassignment isn't possible.

See Also:

WrongArgumentType

hasAssignedSymbolValue

public boolean hasAssignedSymbolValue()

Is a (local or global) value assigned for this symbol?

Specified by:

hasAssignedSymbolValue in interface ISymbol

Returns:

true if this symbol has an assigned value.

getAssignedValue

public IExpr getAssignedValue()

Get the value which is assigned to the symbol or null, if no value is assigned.

Specified by:

getAssignedValue in interface ISymbol

Returns:

null, if no value is assigned.

apply

public final IExpr apply(IExpr... expressions)

Specified by:

apply in interface IExpr

Overrides:

apply in class ExprImpl

Returns:

an IExpr instance with the current expression as head(), and leaves as leaves().

pushLocalVariable

public final void pushLocalVariable()

Create a new variable placeholder on the symbols variable stack

Specified by:

pushLocalVariable in interface ISymbol

pushLocalVariable

public final void pushLocalVariable(IExpr expression)

Create a new variable placeholder on the symbols variable stack and set the local value

Specified by:

pushLocalVariable in interface ISymbol

popLocalVariable

public final void popLocalVariable()

Delete the topmost placeholder from the local variable stack

Specified by:

popLocalVariable in interface ISymbol

clear

public final void clear(EvalEngine engine)

Clear the associated rules for this symbol

Specified by:

clear in interface ISymbol

clearAll

public final void clearAll(EvalEngine engine)

Clear all associated rules and attributes for this symbol

Specified by:

clearAll in interface ISymbol

equals

public boolean equals(java.lang.Object obj)

Test if this is equal to b.

Specified by:

equals in interface edu.jas.structure.Element<IExpr>

Overrides:

equals in class java.lang.Object

Returns:

true if this is equal to b, else false.

isSymbolName

public final boolean isSymbolName(java.lang.String name)

Description copied from interface: ISymbol

Returns true, if this symbol has the given name. The comparison of the symbols name with the given name is done according to the Config.PARSER_USE_LOWERCASE_SYMBOLS setting.

Specified by:

isSymbolName in interface ISymbol

evaluate

public IExpr evaluate(EvalEngine engine)

Evaluate an expression

Specified by:

evaluate in interface IExpr

Parameters:

engine - the evaluation engine

Returns:

the evaluated Object or F.NIL if the evaluation is not possible (i.e. the evaluation doesn't change the object).

evaluateHead

public IExpr evaluateHead(IAST ast,
                          EvalEngine engine)

Specified by:

evaluateHead in interface IExpr

evalDownRule

public final IExpr evalDownRule(IEvaluationEngine ee,
                                IExpr expression)

Evaluate the given expression for the "down value" rules associated with this symbol

Specified by:

evalDownRule in interface ISymbol

Returns:

F.NIL if no evaluation was possible

evalDouble

public final double evalDouble()

Evaluate the expression to a Java double value. If the conversion to a double value is not possible, the method throws a WrongArgumentType exception.

Specified by:

evalDouble in interface IExpr

Overrides:

evalDouble in class ExprImpl

Returns:

this expression converted to a Java double value.

evalComplex

public final org.apache.commons.math4.complex.Complex evalComplex()

Evaluate the expression to a INumber value.

Specified by:

evalComplex in interface IExpr

Overrides:

evalComplex in class ExprImpl

Returns:

null if the conversion is not possible.

evalNumber

public final INumber evalNumber()

Evaluate the expression to a INumber value.

Specified by:

evalNumber in interface IExpr

Overrides:

evalNumber in class ExprImpl

Returns:

null if the conversion is not possible.

evalSignedNumber

public final ISignedNumber evalSignedNumber()

Evaluate the expression to a ISignedNumber value.

Specified by:

evalSignedNumber in interface IExpr

Overrides:

evalSignedNumber in class ExprImpl

Returns:

null if the conversion is not possible.

evalUpRule

public final IExpr evalUpRule(IEvaluationEngine ee,
                              IExpr expression)

Evaluate the given expression for the "up value" rules associated with this symbol

Specified by:

evalUpRule in interface ISymbol

Returns:

F.NIL if no evaluation was possible

getAttributes

public final int getAttributes()

Get the Attributes of this symbol (i.e. LISTABLE, FLAT, ORDERLESS,...)

Specified by:

getAttributes in interface ISymbol

Returns:

See Also:

ISymbol.FLAT

getEvaluator

public IEvaluator getEvaluator()

Get the current evaluator for this symbol

Specified by:

getEvaluator in interface ISymbol

Returns:

the evaluator which is associated to this symbol or null if no evaluator is associated

hasLocalVariableStack

public final boolean hasLocalVariableStack()

Is a local variable stack created for this symbol ?

Specified by:

hasLocalVariableStack in interface ISymbol

Returns:

true if this symbol has a local variable stack

get

public final IExpr get()

Get the topmost value from the local variable stack

Specified by:

get in interface ISymbol

Returns:

null if no local variable is defined

set

public final void set(IExpr value)

Set the value of the local variable on top of the local variable stack

Specified by:

set in interface ISymbol

hashCode

public int hashCode()

Hashcode of this Element.

Specified by:

hashCode in interface edu.jas.structure.Element<IExpr>

Overrides:

hashCode in class java.lang.Object

Returns:

the hashCode.

hierarchy

public int hierarchy()

A unique integer ID for the implementation of this expression

Specified by:

hierarchy in interface IExpr

Returns:

a unique integer id for the implementation of this expression

isString

public final boolean isString(java.lang.String str)

Tests if this symbols name equals the given string

Specified by:

isString in interface ISymbol

Returns:

putDownRule

public final IPatternMatcher putDownRule(ISymbol.RuleType symbol,
                                         boolean equalRule,
                                         IExpr leftHandSide,
                                         IExpr rightHandSide,
                                         boolean packageMode)

Associate a new "down value" rule with default priority to this symbol.

Specified by:

putDownRule in interface ISymbol

Parameters:

symbol - which of the symbols Set, SetDelayed, UpSet, UpSetDelayed was used for defining this rule

equalRule - true if the leftHandSide could be matched with equality

packageMode - true if we are on "package mode"

Returns:

See Also:

PatternMap.DEFAULT_RULE_PRIORITY

putDownRule

public final IPatternMatcher putDownRule(ISymbol.RuleType setSymbol,
                                         boolean equalRule,
                                         IExpr leftHandSide,
                                         IExpr rightHandSide,
                                         int priority,
                                         boolean packageMode)

Associate a new rule with the given priority to this symbol.
Rules with lower numbers have higher priorities.

Specified by:

putDownRule in interface ISymbol

Parameters:

setSymbol - which of the symbols Set, SetDelayed, UpSet, UpSetDelayed was used for defining this rule

equalRule - true if the leftHandSide could be matched with equality

priority - the priority of the rule

packageMode - true if we are on "package mode"

Returns:

See Also:

PatternMap.DEFAULT_RULE_PRIORITY

removeRule

public final void removeRule(ISymbol.RuleType setSymbol,
                             boolean equalRule,
                             IExpr leftHandSide,
                             boolean packageMode)

Specified by:

removeRule in interface ISymbol

putDownRule

public final PatternMatcher putDownRule(PatternMatcherAndInvoker pmEvaluator)

Associate a new rule, which invokes a method, to this symbol.

Specified by:

putDownRule in interface ISymbol

putUpRule

public final IPatternMatcher putUpRule(ISymbol.RuleType symbol,
                                       boolean equalRule,
                                       IAST leftHandSide,
                                       IExpr rightHandSide)

Associate a new "up value" rule with default priority to this symbol.

Specified by:

putUpRule in interface ISymbol

Parameters:

symbol - which of the symbols Set, SetDelayed, UpSet, UpSetDelayed was used for defining this rule

equalRule - true if the leftHandSide could be matched with equality

Returns:

See Also:

PatternMap.DEFAULT_RULE_PRIORITY

putUpRule

public final IPatternMatcher putUpRule(ISymbol.RuleType setSymbol,
                                       boolean equalRule,
                                       IAST leftHandSide,
                                       IExpr rightHandSide,
                                       int priority)

Associate a new "up value" rule with the given priority to this symbol.
Rules with lower numbers have higher priorities.

Specified by:

putUpRule in interface ISymbol

Parameters:

setSymbol - which of the symbols Set, SetDelayed, UpSet, UpSetDelayed was used for defining this rule

equalRule - true if the leftHandSide could be matched with equality

priority - the priority of the rule

Returns:

See Also:

PatternMap.DEFAULT_RULE_PRIORITY

setAttributes

public final void setAttributes(int attributes)

Set the Attributes of this symbol (i.e. LISTABLE, FLAT, ORDERLESS,...)

Specified by:

setAttributes in interface ISymbol

Parameters:

attributes - the Attributes of this symbol

setEvaluator

public final void setEvaluator(IEvaluator evaluator)

Set the current evaluator which is associated to this symbol

Specified by:

setEvaluator in interface ISymbol

compareTo

public int compareTo(IExpr expr)

Compares this expression with the specified expression for order. Returns a negative integer, zero, or a positive integer as this expression is canonical less than, equal to, or greater than the specified expression.

Specified by:

compareTo in interface edu.jas.structure.Element<IExpr>

Specified by:

compareTo in interface java.lang.Comparable<IExpr>

Specified by:

compareTo in interface IExpr

Overrides:

compareTo in class ExprImpl

Returns:

0 if this is equal to b, -1 if this is less then b, else +1.

isAtom

public final boolean isAtom()

Test if this expression is an atomic expression (i.e. no AST expression)

Specified by:

isAtom in interface IExpr

isConstant

public final boolean isConstant()

Test if this expression is a symbol with attribute Constant. Therefore numbers return false for this method!

Specified by:

isConstant in interface IExpr

See Also:

#isRealFunction(), IExpr.isNumericFunction()

isE

public final boolean isE()

Test if this expression equals E (base of the natural logarithm; approximately equal to 2.71828...) in symbolic or numeric mode.
See e (mathematical constant)

Specified by:

isE in interface IExpr

isTrue

public boolean isTrue()

Test if this expression equals the symbol True.

Specified by:

isTrue in interface IExpr

Returns:

true if the expression equals symbol True and false in all other cases

isValue

public final boolean isValue()

Returns true, if this symbol or ast expression is bound to a value (i.e. the evaluation returns an assigned value).

Specified by:

isValue in interface IExpr

isVariable

public boolean isVariable()

Test if this expression is a symbol which doesn't has attribute Constant.

Specified by:

isVariable in interface IExpr

See Also:

IExpr.isConstant(), IExpr.isSymbol()

isFalse

public boolean isFalse()

Test if this expression equals the symbol "False"

Specified by:

isFalse in interface IExpr

isIndeterminate

public boolean isIndeterminate()

Test if this expression is representing Indeterminate

Specified by:

isIndeterminate in interface IExpr

isNegative

public boolean isNegative()

Test if this object is a negative signed number. For an IAST object the method checks, if it is a numeric constant. If the IAST object evaluates to a negative numeric expression this method returns true.

Specified by:

isNegative in interface IExpr

Returns:

true, if this < 0; false in all other case.

isPi

public final boolean isPi()

Test if this expression equals Pi (the ratio of a circle's circumference to its diameter, approx. 3.141592...) in symbolic or numeric mode.
See Pi

Specified by:

isPi in interface IExpr

isPolynomial

public boolean isPolynomial(ISymbol variable)

Test if this expression is a polynomial for the given variable.

Note: if the variable is set to null, this method returns true for a Symbol expression.

Specified by:

isPolynomial in interface IExpr

isPolynomial

public boolean isPolynomial(IAST variables)

Test if this expression is a polynomial for the given list of variables.

Note: if the list contains no argument, this method returns true for a Symbol expression.

Specified by:

isPolynomial in interface IExpr

Parameters:

variables - a list of variables or an empty list

Returns:

true if this expression is a polynomial; falseotherwise

isPolynomialOfMaxDegree

public boolean isPolynomialOfMaxDegree(ISymbol variable,
                                       long maxDegree)

Test if this expression is a polynomial of maxDegree (i.e. the maximum exponent <= maxDegree) for the given variable.

Specified by:

isPolynomialOfMaxDegree in interface IExpr

maxDegree - the maximum degree of the polynomial; maxDegree must be greater 0

isPositive

public boolean isPositive()

Test if this object is a positive signed number. For an IAST object the method checks, if it is a numeric constant. If the IAST object evaluates to a positive numeric expression this method returns true.

Specified by:

isPositive in interface IExpr

Returns:

true, if this > 0; false in all other case.

head

public ISymbol head()

If this object is an instance of IAST get the first element (offset 0) of the IAST list (i.e. get(0) ).

Specified by:

head in interface IExpr

Specified by:

head in class ExprImpl

Returns:

the head of the expression, which must not be null.

getSymbolName

public final java.lang.String getSymbolName()

Get the pure symbol name string

Specified by:

getSymbolName in interface ISymbol

Returns:

variables2Slots

public IExpr variables2Slots(java.util.Map<IExpr,IExpr> map,
                             java.util.Collection<IExpr> variableCollector)

Convert the variables (i.e. expressions of type ISymbol which aren't constants) in this expression into Slot[] s.

Specified by:

variables2Slots in interface IExpr

Overrides:

variables2Slots in class ExprImpl

Parameters:

map - for every given symbol argument return the associated unique slot from this map

variableCollector - collects the variables which are used in the replacement process

Returns:

F.NIL if no variable symbol was found.

internalFormString

public java.lang.String internalFormString(boolean symbolsAsFactoryMethod,
                                           int depth)

Return the internal Java form of this expression.

Specified by:

internalFormString in interface IExpr

Overrides:

internalFormString in class ExprImpl

Parameters:

symbolsAsFactoryMethod - if true use the F.symbol() method, otherwise print the symbol name.

depth - the recursion depth of this call. 0 indicates "recurse without a limit".

internalScalaString

public java.lang.String internalScalaString(boolean symbolsAsFactoryMethod,
                                            int depth)

Return the internal Scala form of this expression.

Specified by:

internalScalaString in interface IExpr

Overrides:

internalScalaString in class ExprImpl

Parameters:

symbolsAsFactoryMethod - if true use the F.symbol() method, otherwise print the symbol name.

depth - the recursion depth of this call. 0 indicates "recurse without a limit".

internalJavaString

public java.lang.String internalJavaString(boolean symbolsAsFactoryMethod,
                                           int depth,
                                           boolean useOperators)

Return the internal Java form of this expression.

Specified by:

internalJavaString in interface IExpr

Overrides:

internalJavaString in class ExprImpl

Parameters:

symbolsAsFactoryMethod - if true use the F.symbol() method, otherwise print the symbol name.

depth - the recursion depth of this call. 0 indicates "recurse without a limit".

useOperators - use operators instead of function names for representation of Plus, Times, Power,...

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

fullFormString

public java.lang.String fullFormString()

Return the FullForm() of this expression

Specified by:

fullFormString in interface IExpr

Overrides:

fullFormString in class ExprImpl

definition

public java.util.List<IAST> definition()

Return a list of the rules associated to this symbol

Specified by:

definition in interface ISymbol

Returns:

getDefaultValue

public IExpr getDefaultValue()

Get the general default value for this symbol (i.e. 1 is the default value for Times, 0 is the default value for Plus). The general default value is used in pattern-matching for expressions like a_. * b_. + c_

Specified by:

getDefaultValue in interface ISymbol

Returns:

the default value or null if undefined.

getDefaultValue

public IExpr getDefaultValue(int pos)

Get the default value at the arguments position for this symbol (i.e. 1 is the default value for Power at position 2). The default value is used in pattern-matching for expressions like a ^ b_.

Specified by:

getDefaultValue in interface ISymbol

Parameters:

pos - the position for the default value

Returns:

the default value or null if undefined.

setDefaultValue

public void setDefaultValue(IExpr expr)

Set the general default value for this symbol (i.e. 1 is the default value for Times, 0 is the default value for Plus). The general default value is used in pattern-matching for expressions like a_. * b_. + c_

Specified by:

setDefaultValue in interface ISymbol

Parameters:

expr - the general default value

See Also:

ISymbol.getDefaultValue()

setDefaultValue

public void setDefaultValue(int pos,
                            IExpr expr)

Set the default value at the arguments position for this symbol (i.e. 1 is the default value for Power at position 2). The default value is used in pattern-matching for expressions like a ^ b_.

Specified by:

setDefaultValue in interface ISymbol

Parameters:

pos - the position for the default value

expr - the default value for the given position

See Also:

ISymbol.getDefaultValue(int)

definitionToString

public java.lang.String definitionToString()
                                    throws java.io.IOException

Return the rules associated to this symbol in String representation

Specified by:

definitionToString in interface ISymbol

Returns:

the String representation of the symbol definition

Throws:

java.io.IOException

readResolve

public java.lang.Object readResolve()
                             throws java.io.ObjectStreamException

Throws:

java.io.ObjectStreamException

readRules

public void readRules(java.io.ObjectInputStream stream)
               throws java.io.IOException,
                      java.lang.ClassNotFoundException

Deserialize the rules associated to this object

Specified by:

readRules in interface ISymbol

Throws:

java.io.IOException

java.lang.ClassNotFoundException

writeRules

public boolean writeRules(java.io.ObjectOutputStream stream)
                   throws java.io.IOException

Serialize the rule definitions associated to this symbol

Specified by:

writeRules in interface ISymbol

Returns:

false if the symbol contains no rule definion.

Throws:

java.io.IOException

containsRules

public boolean containsRules()

Check if ths symbol contains a "DownRule" or "UpRule"

Specified by:

containsRules in interface ISymbol

Returns:

true if this symbol contains a "DownRule" or "UpRule"

createRulesData

public final void createRulesData(int[] sizes)

Create internal rules data structure with precalculated sizes

• index 0 - number of equal rules in RULES

Specified by:

createRulesData in interface ISymbol

accept

public <T> T accept(IVisitor<T> visitor)

Accept a visitor with return type T

Specified by:

accept in interface IExpr

accept

public boolean accept(IVisitorBoolean visitor)

Accept a visitor with return type boolean

Specified by:

accept in interface IExpr

accept

public int accept(IVisitorInt visitor)

Accept a visitor with return type int

Specified by:

accept in interface IExpr

Returns:

accept

public long accept(IVisitorLong visitor)

Accept a visitor with return type long

Specified by:

accept in interface IExpr

Returns:

mapConstantDouble

public IExpr mapConstantDouble(INumericFunction<IExpr> function)

If this symbol has attribute ISymbol.CONSTANT and the symbol's evaluator is of instance INumericConstant, then apply the constants double value to the given function and return the result, otherwise return F.NIL.

Specified by:

mapConstantDouble in interface ISymbol

Parameters:

function - applys the function to a double value, resulting in an object of type IExpr.

Returns:

the resulting expression from the function or F.NIL.

See Also:

Abs, Ceiling, Floor

negate

public IExpr negate()

Description copied from class: ExprImpl

Negate this.

Specified by:

negate in interface edu.jas.structure.AbelianGroupElem<IExpr>

Specified by:

negate in interface org.apache.commons.math4.FieldElement<IExpr>

Overrides:

negate in class ExprImpl

Returns:

- this.