gaia2::Filter Class Reference

The Filter class allows to check whether a predicate is true for a given Point. More...

#include <filter.h>

Inheritance diagram for gaia2::Filter:

Public Member Functions
	Filter (const Filter &filter)
void	updateVariables ()
	Look in the predicate/value tree for all the variables it can find and put them inside their respective *VarList member variables. More...
bool	needsBinding () const
	Returns whether this filter needs to be bound to a specific layout. More...
void	bindToLayout (const PointLayout &layout)
void	bindToPointAttributes ()
bool	isTrue (const Point *p) const
	Returns whether the filter predicate is true for the given point.
bool	isAlwaysTrue () const
	Returns whether the filter predicate is always true, regardless of the given point.
const parser::Predicate *	pred () const
QString	toString () const

Static Public Member Functions
static Filter *	parse (const QString &str)
	Parses a given string and returns the newly created Filter object.
static int	opFromString (const QString &str)
static int	opFromString (const std::string &str)

Protected Member Functions
void	clear ()
void	clearVariables ()
void	updateVariables (parser::Predicate *pred)
void	updateVariables (parser::Value *value)
void	updateVariables (parser::Label *label)

Static Protected Member Functions
static Filter *	stealDataFrom (const Filter &other)

Protected Attributes
parser::Predicate *	_pred
QList< parser::ValueVariable * >	_valueVarList
QList< parser::LabelVariable * >	_labelVarList
QList< parser::LabelPointID * >	_pointVarList
QStringList	_slist
QList< Real >	_vlist
const Point *	_currentPoint

Friends
class	parser::FilterParser
template<typename SearchPointType , typename DataSetType >
class	BaseQueryOptimizer
void	parser::yy_reduce (parser::yyParser *, int)

Detailed Description

The Filter class allows to check whether a predicate is true for a given Point.

To use it, you first need to instantiate it (usually returned by the FilterParser::parse() method), and then bind it to a specific layout (so that variables used in the query are bound to the variables in the layout). You can then call Filter::isTrue() method with a Point as argument to know whether the predicate is true for the given Point or not.

Member Function Documentation

bool gaia2::Filter::needsBinding

(

)

const

Returns whether this filter needs to be bound to a specific layout.

A filter will need to be bound when it has at least one value or label variable, otherwise it is free (and most probably useless!).

Referenced by gaia2::BaseView< DataSetType, PointType, SearchPointType, DistanceType >::validate().

void gaia2::Filter::updateVariables

(

)

Look in the predicate/value tree for all the variables it can find and put them inside their respective *VarList member variables.

This needs to be called if you want your filter to be valid, otherwise it might do weird things (such as crash your program, corrupt your data, ...).

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

• src/parser/filter.h
• src/parser/filter.cpp