QwtLogTransform Class Reference

Logarithmic transformation. More...

#include <qwt_transform.h>

Inheritance diagram for QwtLogTransform:

Public Member Functions
	QwtLogTransform ()
	Constructor.
	~QwtLogTransform () override
	Destructor.
virtual double	transform (double value) const override
	Transformation function - log(value)
virtual double	invTransform (double value) const override
	Inverse transformation function - exp(value)
virtual double	bounded (double value) const override
	Bounded function - qBound(LogMin, value, LogMax)
virtual QwtTransform *	copy () const override
	Clone of the transformation.
Public Member Functions inherited from QwtTransform
	QwtTransform ()
	Constructor.
virtual	~QwtTransform ()
	Destructor.

Static Public Attributes
static const double	LogMin = 1.0e-150
	Smallest allowed value for logarithmic scales: 1.0e-150.
static const double	LogMax = 1.0e150
	Largest allowed value for logarithmic scales: 1.0e150.

Detailed Description

Logarithmic transformation.

QwtLogTransform modifies the values using log() and exp().

Note

In the calculations of QwtScaleMap the base of the log function has no effect on the mapping. So QwtLogTransform can be used for log2(), log10() or any other logarithmic scale.

Constructor & Destructor Documentation

QwtLogTransform()

QwtLogTransform::QwtLogTransform

(

)

Constructor.

Default constructor.

Member Function Documentation

bounded()

double QwtLogTransform::bounded ( double  value ) const

overridevirtual

Bounded function - qBound(LogMin, value, LogMax)

Bounded function.

Parameters

value

Value to be bounded

Returns

qBound( LogMin, value, LogMax )

Reimplemented from QwtTransform.

copy()

QwtTransform * QwtLogTransform::copy ( ) const

overridevirtual

Clone of the transformation.

Returns

New QwtLogTransform instance

Implements QwtTransform.

invTransform()

double QwtLogTransform::invTransform ( double  value ) const

overridevirtual

Inverse transformation function - exp(value)

Inverse transform function.

Parameters

value

Value to be transformed

Returns

exp( value )

Implements QwtTransform.

transform()

double QwtLogTransform::transform ( double  value ) const

overridevirtual

Transformation function - log(value)

Transform function.

Parameters

value

Value to be transformed

Returns

log( value )

Implements QwtTransform.

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

• /home/runner/work/QWT/QWT/src/core/qwt_transform.h
• /home/runner/work/QWT/QWT/src/core/qwt_transform.cpp