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QwtScaleTransformation

QwtScaleTransformation

Section: C Library Functions (3) Updated: 22 Mar 2009
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NAME

QwtScaleTransformation - Operations for linear or logarithmic (base 10) transformations.

 

SYNOPSIS


#include <qwt_scale_map.h>

 

Public Types


enum Type { Linear, Log10, Other }
 

Public Member Functions


QwtScaleTransformation (Type type)

virtual ~QwtScaleTransformation ()

virtual double xForm (double x, double s1, double s2, double p1, double p2) const

virtual double invXForm (double x, double s1, double s2, double p1, double p2) const

Type type () const

virtual QwtScaleTransformation * copy () const
 

Detailed Description

Operations for linear or logarithmic (base 10) transformations.  

Constructor & Destructor Documentation

 

QwtScaleTransformation::QwtScaleTransformation (Type type)

Constructor for a linear transformation.

 

QwtScaleTransformation::~QwtScaleTransformation () [virtual]

Destructor.

 

Member Function Documentation

 

QwtScaleTransformation * QwtScaleTransformation::copy () const [virtual]

Create a clone of the transformation.

 

double QwtScaleTransformation::invXForm (double p, double p1, double p2, double s1, double s2) const [virtual]

Transform a value from a linear to a logarithmic interval.

Parameters:

x value related to the linear interval [p1, p2]
p1 first border of linear interval
p2 first border of linear interval
s1 first border of logarithmic interval
s2 first border of logarithmic interval

Returns:

exp((x - p1) / (p2 - p1) * log(s2 / s1)) * s1;

 

Type QwtScaleTransformation::type () const [inline]

Returns:

Transformation type

 

double QwtScaleTransformation::xForm (double s, double s1, double s2, double p1, double p2) const [virtual]

Transform a value between 2 linear intervals.

Parameters:

x value related to the interval [x1, x2]
x1 first border of source interval
x2 first border of source interval
y1 first border of target interval
y2 first border of target interval

Returns:

linear mapping:
y1 + (y2 - y1) / (x2 - x1) * (x - x1)

log10 mapping:
p1 + (p2 - p1) / log(s2 / s1) * log(x / s1)

 

Author

Generated automatically by Doxygen for Qwt User's Guide from the source code.


 

Index

NAME
SYNOPSIS
Public Types
Public Member Functions
Detailed Description
Constructor & Destructor Documentation
QwtScaleTransformation::QwtScaleTransformation (Type type)
QwtScaleTransformation::~QwtScaleTransformation () [virtual]
Member Function Documentation
QwtScaleTransformation * QwtScaleTransformation::copy () const [virtual]
double QwtScaleTransformation::invXForm (double p, double p1, double p2, double s1, double s2) const [virtual]
Type QwtScaleTransformation::type () const [inline]
double QwtScaleTransformation::xForm (double s, double s1, double s2, double p1, double p2) const [virtual]
Author

This document was created by man2html, using the manual pages.
Time: 21:53:53 GMT, April 16, 2011