KnownVariable Class Reference

A variable with a known value. More...

#include <Variable.h>

Inheritance diagram for KnownVariable:

Public Member Functions
	KnownVariable (string cat_, string name_, const MathStructure &o, string title_="", bool is_local=true, bool is_builtin=false, bool is_active=true)
	KnownVariable (string cat_, string name_, string expression_, string title_="", bool is_local=true, bool is_builtin=false, bool is_active=true)
	KnownVariable ()
	KnownVariable (const KnownVariable *variable)
virtual ExpressionItem *	copy () const
virtual void	set (const ExpressionItem *item)
bool	isKnown () const
virtual bool	isExpression () const
virtual string	expression () const
int	subtype () const
virtual void	set (const MathStructure &o)
virtual void	set (string expression_)
virtual const MathStructure &	get ()
virtual bool	representsPositive (bool=false)
virtual bool	representsNegative (bool=false)
virtual bool	representsNonNegative (bool=false)
virtual bool	representsNonPositive (bool=false)
virtual bool	representsInteger (bool=false)
virtual bool	representsNumber (bool=false)
virtual bool	representsRational (bool=false)
virtual bool	representsReal (bool=false)
virtual bool	representsComplex (bool=false)
virtual bool	representsNonZero (bool=false)
virtual bool	representsEven (bool=false)
virtual bool	representsOdd (bool=false)
virtual bool	representsUndefined (bool=false, bool=false, bool=false)
virtual bool	representsBoolean ()
virtual bool	representsNonMatrix ()
Public Member Functions inherited from Variable
	Variable (string cat_, string name_, string title_="", bool is_local=true, bool is_builtin=false, bool is_active=true)
	Variable (const Variable *variable)
virtual int	type () const
Public Member Functions inherited from ExpressionItem
	ExpressionItem (string cat_, string name_, string title_="", string descr_="", bool is_local=true, bool is_builtin=false, bool is_active=true)
virtual bool	destroy ()
bool	isRegistered () const
void	setRegistered (bool is_registered)
	For internal use.
virtual const string &	name (bool use_unicode=false, bool(*can_display_unicode_string_function)(const char *, void *)=NULL, void *can_display_unicode_string_arg=NULL) const
virtual const string &	referenceName () const
virtual const ExpressionName &	preferredName (bool abbreviation=false, bool use_unicode=false, bool plural=false, bool reference=false, bool(*can_display_unicode_string_function)(const char *, void *)=NULL, void *can_display_unicode_string_arg=NULL) const
virtual const ExpressionName &	preferredInputName (bool abbreviation=false, bool use_unicode=false, bool plural=false, bool reference=false, bool(*can_display_unicode_string_function)(const char *, void *)=NULL, void *can_display_unicode_string_arg=NULL) const
virtual const ExpressionName &	preferredDisplayName (bool abbreviation=false, bool use_unicode=false, bool plural=false, bool reference=false, bool(*can_display_unicode_string_function)(const char *, void *)=NULL, void *can_display_unicode_string_arg=NULL) const
virtual const ExpressionName &	getName (size_t index) const
virtual void	setName (const ExpressionName &ename, size_t index=1, bool force=true)
virtual void	setName (string sname, size_t index, bool force=true)
virtual void	addName (const ExpressionName &ename, size_t index=0, bool force=true)
virtual void	addName (string sname, size_t index=0, bool force=true)
virtual size_t	countNames () const
virtual void	clearNames ()
virtual void	clearNonReferenceNames ()
virtual void	removeName (size_t index)
virtual size_t	hasName (const string &sname, bool case_sensitive=true) const
virtual size_t	hasNameCaseSensitive (const string &sname) const
virtual const ExpressionName &	findName (int abbreviation=-1, int use_unicode=-1, int plural=-1, bool(*can_display_unicode_string_function)(const char *, void *)=NULL, void *can_display_unicode_string_arg=NULL) const
virtual const string &	title (bool return_name_if_no_title=true, bool use_unicode=false, bool(*can_display_unicode_string_function)(const char *, void *)=NULL, void *can_display_unicode_string_arg=NULL) const
virtual void	setTitle (string title_)
virtual const string &	description () const
virtual void	setDescription (string descr_)
virtual const string &	category () const
virtual void	setCategory (string cat_)
virtual bool	hasChanged () const
virtual void	setChanged (bool has_changed)
virtual bool	isLocal () const
virtual bool	setLocal (bool is_local=true, int will_be_active=-1)
virtual bool	isBuiltin () const
virtual bool	isApproximate () const
virtual void	setApproximate (bool is_approx=true)
virtual int	precision () const
virtual void	setPrecision (int prec)
virtual bool	isActive () const
virtual void	setActive (bool is_active)
virtual bool	isHidden () const
virtual void	setHidden (bool is_hidden)
virtual int	refcount () const
virtual void	ref ()
virtual void	unref ()
virtual void	ref (ExpressionItem *o)
virtual void	unref (ExpressionItem *o)
virtual ExpressionItem *	getReferencer (size_t index=1) const
virtual bool	changeReference (ExpressionItem *o_from, ExpressionItem *o_to)

Protected Attributes
MathStructure *	mstruct
bool	b_expression
int	calculated_precision
string	sexpression
Protected Attributes inherited from ExpressionItem
string	scat
string	stitle
string	sdescr
bool	b_local
bool	b_changed
bool	b_builtin
bool	b_approx
bool	b_active
bool	b_registered
bool	b_hidden
bool	b_destroyed
int	i_ref
int	i_precision
vector< ExpressionItem * >	v_refs
vector< ExpressionName >	names

Detailed Description

A variable with a known value.

Known variables have an associated value. The value can be a simple number or a full mathematical expression. The known variable class is used both for variable values and constants.

The value can be provided as an expression in the form of a text string or as a mathematical value in the form of an object of the MathStructure class. The text string is parsed when needed, which saves time when loading many variable definitions which might not be used, at least not immediately.

Constructor & Destructor Documentation

KnownVariable::KnownVariable	(	string	cat_,
		string	name_,
		const MathStructure &	o,
		string	title_ = "",
		bool	is_local = true,
		bool	is_builtin = false,
		bool	is_active = true
	)

Create a known variable with a value.

Parameters

cat_	Category that the variable belongs to.
name_	Initial name of the variable.
o	Value.
title_	Descriptive name.
is_local	If the variable is local/user-defined or global.
is_builtin	If the variable is builtin and not modifiable.
is_active	If the variable is active and can be used in expressions.

KnownVariable::KnownVariable	(	string	cat_,
		string	name_,
		string	expression_,
		string	title_ = "",
		bool	is_local = true,
		bool	is_builtin = false,
		bool	is_active = true
	)

Create a known variable with an text string expression.

Parameters

cat_	Category that the variable belongs to.
name_	Initial name of the variable.
expression_	Expression.
title_	Descriptive name.
is_local	If the variable is local/user-defined or global.
is_builtin	If the variable is builtin and not modifiable.
is_active	If the variable is active and can be used in expressions.

KnownVariable::KnownVariable

(

)

Create an empty known variable. Primarily for internal use.

KnownVariable::KnownVariable

(

const KnownVariable *

variable

)

Create a copy of a known variable.

Parameters

variable

Known variable to copy.

Member Function Documentation

virtual string KnownVariable::expression ( ) const

virtual

Returns the variable's string expression or an empty string if it has not got an expression.

Returns

The variable's expression.

virtual const MathStructure& KnownVariable::get ( )

virtual

Returns the value of the variable. If no value is set or parsed and an expression is set, the expression is parsed and resulting value returned.

Returns

The value of the variable..

Reimplemented in DynamicVariable.

virtual bool KnownVariable::isExpression ( ) const

virtual

Returns if the variable has an text string expression instead of a value.

Returns

True if the variable has an expression instead of a value.

bool KnownVariable::isKnown ( ) const

inlinevirtual

Returns if the variable has a known value (as oppossed to assumptions).

Returns

true if the variable is of class KnownVariable, false if UnknownVariable.

Implements Variable.

virtual bool KnownVariable::representsPositive ( bool  = false )

virtual

Returns if the variable represents a positive value.

Reimplemented from Variable.

Reimplemented in DynamicVariable.

virtual void KnownVariable::set ( const MathStructure &  o )

virtual

Sets the value of the variable. If expression is set, it is cleared.

Parameters

o

Value.

Reimplemented in DynamicVariable.

virtual void KnownVariable::set ( string  expression_ )

virtual

Sets the text string expression of the variable. The value is cleared.

Parameters

expression_

Expression.

Reimplemented in DynamicVariable.

int KnownVariable::subtype ( ) const

inlinevirtual

Returns the subtype of the variable, corresponding to which subsubclass the object belongs to.

Returns

VariableSubtype.

Reimplemented from Variable.

References SUBTYPE_KNOWN_VARIABLE.

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The documentation for this class was generated from the following file:

• libqalculate/Variable.h