QwtScaleEngine Class Reference

Base class for scale engines. More...

#include <qwt_scale_engine.h>

Inheritance diagram for QwtScaleEngine:

Classes
class	PrivateData

Public Types
enum	Attribute {   NoAttribute = 0x00 , IncludeReference = 0x01 , Symmetric = 0x02 , Floating = 0x04 ,   Inverted = 0x08 }
	Layout attributes. More...

Public Member Functions
	QwtScaleEngine (uint base=10)
	Constructor.
virtual	~QwtScaleEngine ()
	Destructor.
void	setBase (uint base)
	Set the base.
uint	base () const
	Return base of the scale engine.
void	setAttribute (Attribute, bool on=true)
	Set an attribute.
bool	testAttribute (Attribute) const
	Test if an attribute is enabled.
void	setAttributes (Attributes)
	Set attributes.
Attributes	attributes () const
	Return scale attributes.
void	setReference (double)
	Set the reference value.
double	reference () const
	Return the reference value.
void	setMargins (double lower, double upper)
	Set the margins.
double	lowerMargin () const
	Return the margin at the lower end of the scale.
double	upperMargin () const
	Return the margin at the upper end of the scale.
virtual void	autoScale (int maxNumSteps, double &x1, double &x2, double &stepSize) const =0
	Align and divide an interval.
virtual QwtScaleDiv	divideScale (double x1, double x2, int maxMajorSteps, int maxMinorSteps, double stepSize=0.0) const =0
	Calculate a scale division.
void	setTransformation (QwtTransform *)
	Set the transformation.
QwtTransform *	transformation () const
	Create and return a clone of the transformation of the engine.

Protected Member Functions
bool	contains (const QwtInterval &, double value) const
	Check if an interval contains a value.
QList< double >	strip (const QList< double > &, const QwtInterval &) const
	Strip values outside an interval.
double	divideInterval (double intervalSize, int numSteps) const
	Divide an interval.
QwtInterval	buildInterval (double value) const
	Build an interval around a value.

Detailed Description

Base class for scale engines.

Member Enumeration Documentation

Attribute

enum QwtScaleEngine::Attribute

Layout attributes.

Enumerator
NoAttribute	No attributes.
IncludeReference	Build a scale which includes the reference() value.
Symmetric	Build a scale which is symmetric to the reference() value.
Floating	The endpoints of the scale are supposed to be equal the outmost included values plus the specified margins (see setMargins()). If this attribute is not set, the endpoints of the scale will be integer multiples of the step size.
Inverted	Turn the scale upside down.

Constructor & Destructor Documentation

QwtScaleEngine()

QwtScaleEngine::QwtScaleEngine ( uint  base = 10 )

explicit

Constructor.

Member Function Documentation

attributes()

QwtScaleEngine::Attributes QwtScaleEngine::attributes

(

)

const

Return scale attributes.

Returns

the attributes

autoScale()

virtual void QwtScaleEngine::autoScale ( int  maxNumSteps, double &  x1, double &  x2, double &  stepSize  ) const

pure virtual

Align and divide an interval.

Implemented in QwtDateScaleEngine, QwtLinearScaleEngine, and QwtLogScaleEngine.

base()

uint QwtScaleEngine::base

(

)

const

Return base of the scale engine.

Returns

the base

buildInterval()

QwtInterval QwtScaleEngine::buildInterval ( double  value ) const

protected

Build an interval around a value.

contains()

bool QwtScaleEngine::contains ( const QwtInterval &  interval, double  value  ) const

protected

Check if an interval contains a value.

Check if an interval "contains" a value.

divideInterval()

double QwtScaleEngine::divideInterval ( double  intervalSize, int  numSteps  ) const

protected

Divide an interval.

Calculate a step size for an interval size.

divideScale()

virtual QwtScaleDiv QwtScaleEngine::divideScale ( double  x1, double  x2, int  maxMajorSteps, int  maxMinorSteps, double  stepSize = 0.0  ) const

pure virtual

Calculate a scale division.

Implemented in QwtDateScaleEngine, QwtLinearScaleEngine, and QwtLogScaleEngine.

lowerMargin()

double QwtScaleEngine::lowerMargin

(

)

const

Return the margin at the lower end of the scale.

Returns

the lower margin

reference()

double QwtScaleEngine::reference

(

)

const

Return the reference value.

Returns

the reference value

setAttribute()

void QwtScaleEngine::setAttribute	(	Attribute	attribute,
		bool	on = true
	)

Set an attribute.

Change a scale attribute.

setAttributes()

void QwtScaleEngine::setAttributes

(

Attributes

attributes

)

Set attributes.

Change the scale attribute.

setBase()

void QwtScaleEngine::setBase

(

uint

base

)

Set the base.

Set the base of the scale engine.

setMargins()

void QwtScaleEngine::setMargins	(	double	lower,
		double	upper
	)

Set the margins.

Specify margins at the scale's endpoints.

setReference()

void QwtScaleEngine::setReference

(

double

reference

)

Set the reference value.

Specify a reference point.

setTransformation()

void QwtScaleEngine::setTransformation

(

QwtTransform *

transform

)

Set the transformation.

Assign a transformation.

strip()

QList< double > QwtScaleEngine::strip ( const QList< double > &  ticks, const QwtInterval &  interval  ) const

protected

Strip values outside an interval.

Remove ticks from a list, that are not inside an interval.

testAttribute()

bool QwtScaleEngine::testAttribute

(

Attribute

attribute

)

const

Test if an attribute is enabled.

Returns

true if an attribute is set

transformation()

QwtTransform * QwtScaleEngine::transformation

(

)

const

Create and return a clone of the transformation of the engine.

Returns

the transformation

upperMargin()

double QwtScaleEngine::upperMargin

(

)

const

Return the margin at the upper end of the scale.

Returns

the upper margin

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

• /home/runner/work/QWT/QWT/src/plot/qwt_scale_engine.h
• /home/runner/work/QWT/QWT/src/plot/qwt_scale_engine.cpp