QwtLogScaleEngine(3)

🎀 NAME 🎀

okay bestie, this is the QwtLogScaleEngine(3) page from the Library Functions Manual (Qwt User's Guide energy), and the whole point is literally right here: QwtLogScaleEngine is a scale engine for logarithmic scales. no cap. ✨

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🦋 SYNOPSIS 🦋

#include <qwt_scale_engine.h>

Inherits QwtScaleEngine.

💖 Public Member Functions 💖

• QwtLogScaleEngine (uint base=10) — constructor, with the base defaulting to 10 exactly as written.
• virtual ~QwtLogScaleEngine () — destructor. bye bestie 🫶
• virtual void autoScale (int maxNumSteps, double &x1, double &x2, double &stepSize) const override — the override version; details are down in the docs below.
• virtual QwtScaleDiv divideScale (double x1, double x2, int maxMajorSteps, int maxMinorSteps, double stepSize=0.0) const override — calculate a scale division for an interval. slay.

💜 Public Member Functions inherited from QwtScaleEngine 💜

• QwtScaleEngine (uint base=10) — inherited constructor.
• virtual ~QwtScaleEngine () — destructor.
• void setBase (uint base) — inherited, no extra description in the original, just here for completeness.
• uint base () const — inherited, no extra description in the original.
• void setAttribute (Attribute, bool on=true) — inherited, no extra description in the original.
• bool testAttribute (Attribute) const — inherited, no extra description in the original.
• void setAttributes (Attributes) — inherited, no extra description in the original.
• Attributes attributes () const — inherited, no extra description in the original.
• void setReference (double) — specify a reference point.
• double reference () const — inherited, no extra description in the original.
• void setMargins (double lower, double upper) — specify margins at the scale's endpoints.
• double lowerMargin () const — inherited, no extra description in the original.
• double upperMargin () const — inherited, no extra description in the original.
• void setTransformation (QwtTransform *) — inherited, no extra description in the original.
• QwtTransform * transformation () const — inherited, no extra description in the original.

🌸 Protected Member Functions 🌸

• QwtInterval align (const QwtInterval &, double stepSize) const — align an interval to a step size.
• void buildTicks (const QwtInterval &, double stepSize, int maxMinorSteps, QList< double > ticks[QwtScaleDiv::NTickTypes]) const — calculate ticks for an interval.
• QList< double > buildMajorTicks (const QwtInterval &interval, double stepSize) const — calculate major ticks for an interval.
• void buildMinorTicks (const QList< double > &majorTicks, int maxMinorSteps, double stepSize, QList< double > &minorTicks, QList< double > &mediumTicks) const — calculate minor/medium ticks for major ticks.

🌺 Protected Member Functions inherited from QwtScaleEngine 🌺

• bool contains (const QwtInterval &, double value) const — inherited, no extra description in the original.
• QList< double > strip (const QList< double > &, const QwtInterval &) const — inherited, no extra description in the original.
• double divideInterval (double intervalSize, int numSteps) const — inherited, no extra description in the original.
• QwtInterval buildInterval (double value) const — build an interval around a value.

🧚 Additional Inherited Members 🧚

🌈 Public Types inherited from QwtScaleEngine 🌈

enum Attribute { NoAttribute = 0x00, IncludeReference = 0x01, Symmetric = 0x02, Floating = 0x04, Inverted = 0x08 }

• typedef QFlags< Attribute > Attributes — the exact typedef, bestie, no edits.

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💅 Detailed Description 💅

A scale engine for logarithmic scales. literally that's the main character description, and it is iconic. ✨

The step size is measured in decades, aight, and the major step size will be adjusted to fit the pattern $t 1,2,3,5.

⚠️ warning, bestie: the step size as well as the margins are measured in decades.

Definition at line 191 of file qwt_scale_engine.h.

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✨ Constructor & Destructor Documentation ✨

🎀 QwtLogScaleEngine::QwtLogScaleEngine (uint base = 10) [explicit] 🎀

Constructor.

• base — Base of the scale engine.

See also setBase().

Definition at line 776 of file qwt_scale_engine.cpp.

🎀 QwtLogScaleEngine::~QwtLogScaleEngine () [virtual] 🎀

Destructor.

Definition at line 783 of file qwt_scale_engine.cpp.

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🔥 Member Function Documentation 🔥

💜 QwtInterval QwtLogScaleEngine::align (const QwtInterval & interval, double stepSize) const [protected] 💜

Align an interval to a step size. The limits of an interval are aligned that both are integer multiples of the step size.

• interval — Interval.
• stepSize — Step size.

Returns: Aligned interval.

Definition at line 1106 of file qwt_scale_engine.cpp.

💜 void QwtLogScaleEngine::autoScale (int maxNumSteps, double & x1, double & x2, double & stepSize) const [override], [virtual] 💜

Align and divide an interval.

• 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.

Definition at line 797 of file qwt_scale_engine.cpp.

💜 QList< double > QwtLogScaleEngine::buildMajorTicks (const QwtInterval & interval, double stepSize) const [protected] 💜

Calculate major ticks for an interval.

• interval — Interval.
• stepSize — Step size.

Returns: Calculated ticks.

Definition at line 967 of file qwt_scale_engine.cpp.

💜 void QwtLogScaleEngine::buildMinorTicks (const QList< double > & majorTicks, int maxMinorSteps, double stepSize, QList< double > & minorTicks, QList< double > & mediumTicks) const [protected] 💜

Calculate minor/medium ticks for major ticks.

• majorTicks — Major ticks.
• maxMinorSteps — Maximum number of minor steps.
• stepSize — Step size.
• minorTicks — Array to be filled with the calculated minor ticks.
• mediumTicks — Array to be filled with the calculated medium ticks.

Definition at line 1002 of file qwt_scale_engine.cpp.

💜 void QwtLogScaleEngine::buildTicks (const QwtInterval & interval, double stepSize, int maxMinorSteps, QList< double > ticks[QwtScaleDiv::NTickTypes]) const [protected] 💜

Calculate ticks for an interval.

• interval — Interval.
• maxMinorSteps — Maximum number of minor steps.
• stepSize — Step size.
• ticks — Arrays to be filled with the calculated ticks.

See also buildMajorTicks(), buildMinorTicks.

Definition at line 940 of file qwt_scale_engine.cpp.

💜 QwtScaleDiv QwtLogScaleEngine::divideScale (double x1, double x2, int maxMajorSteps, int maxMinorSteps, double stepSize = 0.0) const [override], [virtual] 💜

Calculate a scale division for an interval.

• x1 — First interval limit.
• x2 — Second interval limit.
• maxMajorSteps — Maximum for the number of major steps.
• maxMinorSteps — Maximum number of minor steps.
• stepSize — Step size. If stepSize == 0, the engine calculates one.

Returns: Calculated scale division.

Implements QwtScaleEngine.

Definition at line 879 of file qwt_scale_engine.cpp.

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🫶 Author 🫶

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

okay that's the whole page, bestie 🫶 — footer source/version is Qwt User's Guide and the manual is QwtLogScaleEngine(3); there's no date printed on this footer, so no invented date, periodt. 💖