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/* -*- mode: C++ ; c-file-style: "stroustrup" -*- *****************************
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* Copyright (C) 1997 Josef Wilgen
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* Copyright (C) 2002 Uwe Rathmann
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the Qwt License, Version 1.0
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*****************************************************************************/
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#ifndef QWT_SCALE_ENGINE_H
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#define QWT_SCALE_ENGINE_H
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#include "qwt_global.h"
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#include "qwt_scale_div.h"
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#include "qwt_double_interval.h"
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class QwtScaleTransformation;
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\brief Arithmetic including a tolerance
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class QWT_EXPORT QwtScaleArithmetic
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static int compareEps(
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double value1, double value2, double intervalSize);
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static double ceilEps(double value, double intervalSize);
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static double floorEps(double value, double intervalSize);
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static double divideEps(double interval, double steps);
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static double ceil125(double x);
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static double floor125(double x);
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\brief Base class for scale engines.
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A scale engine trys to find "reasonable" ranges and step sizes
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The layout of the scale can be varied with setOptions().
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Qwt offers implementations for logarithmic (log10)
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and linear scales. Contributions for other types of scale engines
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(date/time, log2 ... ) are welcome.
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class QWT_EXPORT QwtScaleEngine
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//! see QwtScaleEngine::setOption, testOption
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explicit QwtScaleEngine();
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virtual ~QwtScaleEngine();
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void setAttribute(Attribute, bool on = true);
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bool testAttribute(Attribute) const;
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void setAttributes(int);
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int attributes() const;
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void setReference(double reference);
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double reference() const;
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void setMargins(double m1, double m2);
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double loMargin() const;
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double hiMargin() const;
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Align and divide an interval
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\param maxNumSteps Max. number of steps
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\param x1 First limit of the interval (In/Out)
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\param x2 Second limit of the interval (In/Out)
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\param stepSize Step size (Return value)
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virtual void autoScale(int maxNumSteps,
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double &x1, double &x2, double &stepSize) const = 0;
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\brief Calculate a scale division
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\param x1 First interval limit
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\param x2 Second interval limit
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\param maxMajSteps Maximum for the number of major steps
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\param maxMinSteps Maximum number of minor steps
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\param stepSize Step size. If stepSize == 0.0, the scaleEngine
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virtual QwtScaleDiv divideScale(double x1, double x2,
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int maxMajSteps, int maxMinSteps,
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double stepSize = 0.0) const = 0;
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//! \return a transformation
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virtual QwtScaleTransformation *transformation() const = 0;
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bool contains(const QwtDoubleInterval &, double val) const;
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QwtValueList strip(const QwtValueList&, const QwtDoubleInterval &) const;
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double divideInterval(double interval, int numSteps) const;
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QwtDoubleInterval buildInterval(double v) const;
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\brief A scale engine for linear scales
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The step size will fit into the pattern
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\f$\left\{ 1,2,5\right\} \cdot 10^{n}\f$, where n is an integer.
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class QWT_EXPORT QwtLinearScaleEngine: public QwtScaleEngine
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virtual void autoScale(int maxSteps,
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double &x1, double &x2, double &stepSize) const;
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virtual QwtScaleDiv divideScale(double x1, double x2,
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int numMajorSteps, int numMinorSteps,
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double stepSize = 0.0) const;
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virtual QwtScaleTransformation *transformation() const;
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QwtDoubleInterval align(const QwtDoubleInterval&,
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double stepSize) const;
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const QwtDoubleInterval &, double stepSize, int maxMinSteps,
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QwtValueList ticks[QwtScaleDiv::NTickTypes]) const;
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void buildMinorTicks(
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const QwtValueList& majorTicks,
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int maxMinMark, double step,
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QwtValueList &, QwtValueList &) const;
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QwtValueList buildMajorTicks(
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const QwtDoubleInterval &interval, double stepSize) const;
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\brief A scale engine for logarithmic (base 10) scales
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The step size is measured in *decades*
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and the major step size will be adjusted to fit the pattern
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\f$\left\{ 1,2,3,5\right\} \cdot 10^{n}\f$, where n is a natural number
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\warning the step size as well as the margins are measured in *decades*.
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class QWT_EXPORT QwtLog10ScaleEngine: public QwtScaleEngine
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virtual void autoScale(int maxSteps,
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double &x1, double &x2, double &stepSize) const;
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virtual QwtScaleDiv divideScale(double x1, double x2,
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int numMajorSteps, int numMinorSteps,
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double stepSize = 0.0) const;
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virtual QwtScaleTransformation *transformation() const;
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QwtDoubleInterval log10(const QwtDoubleInterval&) const;
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QwtDoubleInterval pow10(const QwtDoubleInterval&) const;
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QwtDoubleInterval align(const QwtDoubleInterval&,
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double stepSize) const;
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const QwtDoubleInterval &, double stepSize, int maxMinSteps,
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QwtValueList ticks[QwtScaleDiv::NTickTypes]) const;
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QwtValueList buildMinorTicks(
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const QwtValueList& majorTicks,
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int maxMinMark, double step) const;
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QwtValueList buildMajorTicks(
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const QwtDoubleInterval &interval, double stepSize) const;
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removed
qwt-5.0.1/src/qwt_scale_engine.h
