qwtscaletransformation(3) [debian man page]
QwtScaleTransformation(3) Qwt User's Guide QwtScaleTransformation(3) 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 virtual QwtScaleTransformation * copy () const virtual double invXForm (double x, double p1, double p2, double s1, double s2) const QwtScaleTransformation (Type type) Type type () const virtual double xForm (double x, double s1, double s2, double p1, double p2) const virtual ~QwtScaleTransformation () Detailed Description Operations for linear or logarithmic (base 10) transformations. Constructor &; Destructor Documentation QwtScaleTransformation::QwtScaleTransformation (Typetype) 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 (doublep, doublep1, doublep2, doubles1, doubles2) const [virtual] Transform a value from the coordinate system of the paint device into the coordinate system of a scale. Parameters: p Value related to the coordinate system of the paint device p1 First border of the coordinate system of the paint device p2 Second border of the coordinate system of the paint device s1 First border of the coordinate system of the scale s2 Second border of the coordinate system of the scale Returns: linear mapping: s1 + ( s2 - s1 ) / ( p2 - p1 ) * ( p - p1 ); log10 mapping: exp((p - p1) / (p2 - p1) * log(s2 / s1)) * s1; QwtScaleTransformation::Type QwtScaleTransformation::type () const [inline] Returns: Transformation type double QwtScaleTransformation::xForm (doubles, doubles1, doubles2, doublep1, doublep2) const [virtual] Transform a value from the coordinate system of a scale into the coordinate system of the paint device. Parameters: s Value related to the coordinate system of the scale s1 First border of the coordinate system of the scale s2 Second border of the coordinate system of the scale p1 First border of the coordinate system of the paint device p2 Second border of the coordinate system of the paint device Returns: linear mapping: p1 + (p2 - p1) / (s2 - s1) * (s - s1); log10 mapping: p1 + (p2 - p1) / log(s2 / s1) * log(s / s1); Author Generated automatically by Doxygen for Qwt User's Guide from the source code. Version 5.2.2 Mon Aug 1 2011 QwtScaleTransformation(3)
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QwtLog10ScaleEngine(3) Qwt User's Guide QwtLog10ScaleEngine(3) NAME
QwtLog10ScaleEngine - A scale engine for logarithmic (base 10) scales. SYNOPSIS
#include <qwt_scale_engine.h> Inherits QwtScaleEngine. Public Types enum Attribute { NoAttribute = 0, IncludeReference = 1, Symmetric = 2, Floating = 4, Inverted = 8 } Public Member Functions int attributes () const virtual void autoScale (int maxSteps, double &x1, double &x2, double &stepSize) const virtual QwtScaleDiv divideScale (double x1, double x2, int numMajorSteps, int numMinorSteps, double stepSize=0.0) const double lowerMargin () const double reference () const void setAttribute (Attribute, bool on=true) void setAttributes (int) void setMargins (double lower, double upper) void setReference (double reference) bool testAttribute (Attribute) const virtual QwtScaleTransformation * transformation () const double upperMargin () const Protected Member Functions QwtDoubleInterval buildInterval (double v) const bool contains (const QwtDoubleInterval &, double val) const double divideInterval (double interval, int numSteps) const QwtDoubleInterval log10 (const QwtDoubleInterval &) const QwtDoubleInterval pow10 (const QwtDoubleInterval &) const QwtValueList strip (const QwtValueList &, const QwtDoubleInterval &) const Detailed Description A scale engine for logarithmic (base 10) scales. ight The step size is measured in *decades* and the major step size will be adjusted to fit the pattern $t 1,2,3,5 Warning: the step size as well as the margins are measured in *decades*. Member Enumeration Documentation enum QwtScaleEngine::Attribute [inherited] .IP o 2 IncludeReference Build a scale which includes the reference() value. o Symmetric Build a scale which is symmetric to the reference() value. o 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. o Inverted Turn the scale upside down. See also: setAttribute(), testAttribute(), reference(), lowerMargin(), upperMargin() Member Function Documentation int QwtScaleEngine::attributes () const [inherited] Return the scale attributes See also: Attribute, setAttributes(), testAttribute() void QwtLog10ScaleEngine::autoScale (intmaxNumSteps, double &x1, double &x2, double &stepSize) const [virtual] Align and divide an interval Parameters: maxNumSteps Max. number of steps x1 First limit of the interval (In/Out) x2 Second limit of the interval (In/Out) stepSize Step size (Out) See also: QwtScaleEngine::setAttribute() Implements QwtScaleEngine. QwtDoubleInterval QwtScaleEngine::buildInterval (doublev) const [protected, inherited] Build an interval for a value. In case of v == 0.0 the interval is [-0.5, 0.5], otherwide it is [0.5 * v, 1.5 * v] bool QwtScaleEngine::contains (const QwtDoubleInterval &interval, doublevalue) const [protected, inherited] Check if an interval 'contains' a value Parameters: interval Interval value Value See also: QwtScaleArithmetic::compareEps() double QwtScaleEngine::divideInterval (doubleintervalSize, intnumSteps) const [protected, inherited] Calculate a step size for an interval size Parameters: intervalSize Interval size numSteps Number of steps Returns: Step size QwtScaleDiv QwtLog10ScaleEngine::divideScale (doublex1, doublex2, intmaxMajSteps, intmaxMinSteps, doublestepSize = 0.0) const [virtual] Calculate a scale division. Parameters: x1 First interval limit x2 Second interval limit maxMajSteps Maximum for the number of major steps maxMinSteps Maximum number of minor steps stepSize Step size. If stepSize == 0, the scaleEngine calculates one. See also: QwtScaleEngine::stepSize(), QwtLog10ScaleEngine::subDivide() Implements QwtScaleEngine. QwtDoubleInterval QwtLog10ScaleEngine::log10 (const QwtDoubleInterval &interval) const [protected] Return the interval [log10(interval.minValue(), log10(interval.maxValue] double QwtScaleEngine::lowerMargin () const [inherited] Returns: the margin at the lower end of the scale The default margin is 0. See also: setMargins() QwtDoubleInterval QwtLog10ScaleEngine::pow10 (const QwtDoubleInterval &interval) const [protected] Return the interval [pow10(interval.minValue(), pow10(interval.maxValue] double QwtScaleEngine::reference () const [inherited] Returns: the reference value See also: setReference(), setAttribute() void QwtScaleEngine::setAttribute (Attributeattribute, boolon = true) [inherited] Change a scale attribute Parameters: attribute Attribute to change on On/Off See also: Attribute, testAttribute() void QwtScaleEngine::setAttributes (intattributes) [inherited] Change the scale attribute Parameters: attributes Set scale attributes See also: Attribute, attributes() void QwtScaleEngine::setMargins (doublelower, doubleupper) [inherited] Specify margins at the scale's endpoints. Parameters: lower minimum distance between the scale's lower boundary and the smallest enclosed value upper minimum distance between the scale's upper boundary and the greatest enclosed value Margins can be used to leave a minimum amount of space between the enclosed intervals and the boundaries of the scale. Warning: o QwtLog10ScaleEngine measures the margins in decades. See also: upperMargin(), lowerMargin() void QwtScaleEngine::setReference (doubler) [inherited] Specify a reference point. Parameters: r new reference value The reference point is needed if options IncludeReference or Symmetric are active. Its default value is 0.0. See also: Attribute QwtValueList QwtScaleEngine::strip (const QwtValueList &ticks, const QwtDoubleInterval &interval) const [protected, inherited] Remove ticks from a list, that are not inside an interval Parameters: ticks Tick list interval Interval Returns: Stripped tick list bool QwtScaleEngine::testAttribute (Attributeattribute) const [inherited] Check if a attribute is set. Parameters: attribute Attribute to be tested See also: Attribute, setAttribute() QwtScaleTransformation * QwtLog10ScaleEngine::transformation () const [virtual] Return a transformation, for logarithmic (base 10) scales Implements QwtScaleEngine. double QwtScaleEngine::upperMargin () const [inherited] Returns: the margin at the upper end of the scale The default margin is 0. See also: setMargins() Author Generated automatically by Doxygen for Qwt User's Guide from the source code. Version 5.2.2 Mon Aug 1 2011 QwtLog10ScaleEngine(3)