Expressions Class Reference

Maintains the current expressions available for generation and plotting. More...

#include <expressions.h>

Inheritance diagram for Expressions:

Signals
void	expressionAdded (PlotExpression *expression)
	Raised when an expression is added. More...
void	expressionRemoved (const PlotExpression *expression)
	Raised when an expression is removed. More...
void	functionRegistered (const FunctionDefinition *function)
	Raised when a function is successfully added via registerFunction(). More...

Public Member Functions
	Expressions (QObject *parent=nullptr)
	Create an expressions data model object. More...
	~Expressions ()
	Destructor.
void	clear (bool suppressSignals=true)
	Delete all expressions optionally suppressing event signals. More...
void	loadExpressions (const QSettings &settings, bool delaySignals=true)
	Load expressions from the given settings. More...
void	saveExpressions (QSettings &settings)
	Save expressions to the given settings. More...
void	addExpression (PlotExpression *expression)
	Adds an expression. More...
bool	removeExpression (PlotExpression *expression)
	Remove expression if it is present. More...
bool	contains (const PlotExpression *expression) const
	Check if expression is a known expression (check by pointer). More...
const QList< PlotExpression * > &	expressions () const
	Access the list of expressions. More...
const PlotFunctionRegister &	functionRegister () const
	Access the function register. More...
bool	registerFunction (FunctionDefinition *functionDef, bool takeOwnership=true)
	Registers a function for use in expressions. More...

Static Public Attributes
static const unsigned	missingTolerance = 50
	Internally used in settings serialisation.

Detailed Description

Maintains the current expressions available for generation and plotting.

This forms the model for use in the UI and for generating expressions from.

Constructor & Destructor Documentation

Expressions::Expressions

(

QObject *

parent = nullptr

)

Create an expressions data model object.

Parameters

parent

The owning object.

Member Function Documentation

void Expressions::addExpression

(

PlotExpression *

expression

)

Adds an expression.

Parameters

expression

The expression to add.

void Expressions::clear

(

bool

suppressSignals = true

)

Delete all expressions optionally suppressing event signals.

Parameters

suppressSignals

True to suppress the expressionRemoved() signal, false to allow it.

bool Expressions::contains

(

const PlotExpression *

expression

)

const

Check if expression is a known expression (check by pointer).

Returns

True if the pointer expression references a known expression.

void Expressions::expressionAdded ( PlotExpression *  expression )

signal

Raised when an expression is added.

Parameters

expression

The added expression.

void Expressions::expressionRemoved ( const PlotExpression *  expression )

signal

Raised when an expression is removed.

Parameters

expression

The removed expression. May be deleted if the signal is delayed.

const QList< PlotExpression * > & Expressions::expressions ( ) const

inline

Access the list of expressions.

Returns

The current expressions.

const PlotFunctionRegister & Expressions::functionRegister ( ) const

inline

Access the function register.

Returns

The function register.

void Expressions::functionRegistered ( const FunctionDefinition *  function )

signal

Raised when a function is successfully added via registerFunction().

Parameters

function

The definition of the function added.

void Expressions::loadExpressions	(	const QSettings &	settings,
		bool	delaySignals = true
	)

Load expressions from the given settings.

Expressions are loaded from the current group in settings, so it should be primed before calling this method.

Parameters

settings	The settings to load from.
delaySignals	True to delay the addExpression() and expressionRemoved() signals until done.

bool Expressions::registerFunction	(	FunctionDefinition *	functionDef,
		bool	takeOwnership = true
	)

Registers a function for use in expressions.

See PlotFunction.

This registers a function in the functionRegister() if possible and raises functionRegistered() on success.

Parameters

functionDef	The definition of the function being registered.
takeOwnership	true to take ownership of the functionDef. This allows it to be deleted by the function register on shutdown.

bool Expressions::removeExpression

(

PlotExpression *

expression

)

Remove expression if it is present.

The caller takes ownership of expression.

Parameters

expression

The expression to remove.

Returns

True if the expression was found and removed.

void Expressions::saveExpressions

(

QSettings &

settings

)

Save expressions to the given settings.

Expressions are saved with the tag 'exp#' where '#' is the expression number, starting from 1. At most expressionCountLimit expressions are stored. After writing existing expressions, the settings are checked for additional, contiguous 'exp#' patterns, which are removed.

For example, we have three expressions, which are written as [ exp1, exp2, exp3 ]. The settings previously contained six expressions, adding [ exp4, exp5, exp6 ]. After saving three expressions, this function tests settings for the existence of 'exp4' and remove it. It then tests for 'exp5', etc and removes the key until key is not found in settings, in this case 'exp7'.

Expressions are saved to the current group in settings.

Parameters

settings

The settings to save to.

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

• expressions.h