QCPCurve Class Reference

A plottable representing a parametric curve in a plot. More...

Inheritance diagram for QCPCurve:

Public Types
enum	LineStyle { lsNone , lsLine }

Public Member Functions
	QCPCurve (QCPAxis *keyAxis, QCPAxis *valueAxis)
QSharedPointer< QCPCurveDataContainer >	data () const
QCPScatterStyle	scatterStyle () const
int	scatterSkip () const
LineStyle	lineStyle () const
void	setData (QSharedPointer< QCPCurveDataContainer > data)
void	setData (const QVector< double > &t, const QVector< double > &keys, const QVector< double > &values, bool alreadySorted=false)
void	setData (const QVector< double > &keys, const QVector< double > &values)
void	setScatterStyle (const QCPScatterStyle &style)
void	setScatterSkip (int skip)
void	setLineStyle (LineStyle style)
void	addData (const QVector< double > &t, const QVector< double > &keys, const QVector< double > &values, bool alreadySorted=false)
void	addData (const QVector< double > &keys, const QVector< double > &values)
void	addData (double t, double key, double value)
void	addData (double key, double value)
virtual double	selectTest (const QPointF &pos, bool onlySelectable, QVariant *details=nullptr) const Q_DECL_OVERRIDE
virtual QCPRange	getKeyRange (bool &foundRange, QCP::SignDomain inSignDomain=QCP::sdBoth) const Q_DECL_OVERRIDE
virtual QCPRange	getValueRange (bool &foundRange, QCP::SignDomain inSignDomain=QCP::sdBoth, const QCPRange &inKeyRange=QCPRange()) const Q_DECL_OVERRIDE
Public Member Functions inherited from QCPAbstractPlottable1D< QCPCurveData >
	QCPAbstractPlottable1D (QCPAxis *keyAxis, QCPAxis *valueAxis)
virtual int	dataCount () const Q_DECL_OVERRIDE
virtual double	dataMainKey (int index) const Q_DECL_OVERRIDE
virtual double	dataSortKey (int index) const Q_DECL_OVERRIDE
virtual double	dataMainValue (int index) const Q_DECL_OVERRIDE
virtual QCPRange	dataValueRange (int index) const Q_DECL_OVERRIDE
virtual QPointF	dataPixelPosition (int index) const Q_DECL_OVERRIDE
virtual bool	sortKeyIsMainKey () const Q_DECL_OVERRIDE
virtual QCPDataSelection	selectTestRect (const QRectF &rect, bool onlySelectable) const Q_DECL_OVERRIDE
virtual int	findBegin (double sortKey, bool expandedRange=true) const Q_DECL_OVERRIDE
virtual int	findEnd (double sortKey, bool expandedRange=true) const Q_DECL_OVERRIDE
virtual QCPPlottableInterface1D *	interface1D () Q_DECL_OVERRIDE
Public Member Functions inherited from QCPAbstractPlottable
	QCPAbstractPlottable (QCPAxis *keyAxis, QCPAxis *valueAxis)
QString	name () const
bool	antialiasedFill () const
bool	antialiasedScatters () const
QPen	pen () const
QBrush	brush () const
QCPAxis *	keyAxis () const
QCPAxis *	valueAxis () const
QCP::SelectionType	selectable () const
bool	selected () const
QCPDataSelection	selection () const
QCPSelectionDecorator *	selectionDecorator () const
void	setName (const QString &name)
void	setAntialiasedFill (bool enabled)
void	setAntialiasedScatters (bool enabled)
void	setPen (const QPen &pen)
void	setBrush (const QBrush &brush)
void	setKeyAxis (QCPAxis *axis)
void	setValueAxis (QCPAxis *axis)
Q_SLOT void	setSelectable (QCP::SelectionType selectable)
Q_SLOT void	setSelection (QCPDataSelection selection)
void	setSelectionDecorator (QCPSelectionDecorator *decorator)
void	coordsToPixels (double key, double value, double &x, double &y) const
const QPointF	coordsToPixels (double key, double value) const
void	pixelsToCoords (double x, double y, double &key, double &value) const
void	pixelsToCoords (const QPointF &pixelPos, double &key, double &value) const
void	rescaleAxes (bool onlyEnlarge=false) const
void	rescaleKeyAxis (bool onlyEnlarge=false) const
void	rescaleValueAxis (bool onlyEnlarge=false, bool inKeyRange=false) const
bool	addToLegend (QCPLegend *legend)
bool	addToLegend ()
bool	removeFromLegend (QCPLegend *legend) const
bool	removeFromLegend () const
Public Member Functions inherited from QCPLayerable
	QCPLayerable (QCustomPlot *plot, QString targetLayer=QString(), QCPLayerable *parentLayerable=nullptr)
bool	visible () const
QCustomPlot *	parentPlot () const
QCPLayerable *	parentLayerable () const
QCPLayer *	layer () const
bool	antialiased () const
void	setVisible (bool on)
Q_SLOT bool	setLayer (QCPLayer *layer)
bool	setLayer (const QString &layerName)
void	setAntialiased (bool enabled)
bool	realVisibility () const

Protected Member Functions
virtual void	draw (QCPPainter *painter) Q_DECL_OVERRIDE
virtual void	drawLegendIcon (QCPPainter *painter, const QRectF &rect) const Q_DECL_OVERRIDE
virtual void	drawCurveLine (QCPPainter *painter, const QVector< QPointF > &lines) const
virtual void	drawScatterPlot (QCPPainter *painter, const QVector< QPointF > &points, const QCPScatterStyle &style) const
void	getCurveLines (QVector< QPointF > *lines, const QCPDataRange &dataRange, double penWidth) const
void	getScatters (QVector< QPointF > *scatters, const QCPDataRange &dataRange, double scatterWidth) const
int	getRegion (double key, double value, double keyMin, double valueMax, double keyMax, double valueMin) const
QPointF	getOptimizedPoint (int otherRegion, double otherKey, double otherValue, double key, double value, double keyMin, double valueMax, double keyMax, double valueMin) const
QVector< QPointF >	getOptimizedCornerPoints (int prevRegion, int currentRegion, double prevKey, double prevValue, double key, double value, double keyMin, double valueMax, double keyMax, double valueMin) const
bool	mayTraverse (int prevRegion, int currentRegion) const
bool	getTraverse (double prevKey, double prevValue, double key, double value, double keyMin, double valueMax, double keyMax, double valueMin, QPointF &crossA, QPointF &crossB) const
void	getTraverseCornerPoints (int prevRegion, int currentRegion, double keyMin, double valueMax, double keyMax, double valueMin, QVector< QPointF > &beforeTraverse, QVector< QPointF > &afterTraverse) const
double	pointDistance (const QPointF &pixelPoint, QCPCurveDataContainer::const_iterator &closestData) const
Protected Member Functions inherited from QCPAbstractPlottable1D< QCPCurveData >
void	getDataSegments (QList< QCPDataRange > &selectedSegments, QList< QCPDataRange > &unselectedSegments) const
void	drawPolyline (QCPPainter *painter, const QVector< QPointF > &lineData) const
Protected Member Functions inherited from QCPAbstractPlottable
virtual QRect	clipRect () const Q_DECL_OVERRIDE
virtual QCP::Interaction	selectionCategory () const Q_DECL_OVERRIDE
void	applyDefaultAntialiasingHint (QCPPainter *painter) const Q_DECL_OVERRIDE
virtual void	selectEvent (QMouseEvent *event, bool additive, const QVariant &details, bool *selectionStateChanged) Q_DECL_OVERRIDE
virtual void	deselectEvent (bool *selectionStateChanged) Q_DECL_OVERRIDE
void	applyFillAntialiasingHint (QCPPainter *painter) const
void	applyScattersAntialiasingHint (QCPPainter *painter) const
Protected Member Functions inherited from QCPLayerable
virtual void	parentPlotInitialized (QCustomPlot *parentPlot)
virtual void	mousePressEvent (QMouseEvent *event, const QVariant &details)
virtual void	mouseMoveEvent (QMouseEvent *event, const QPointF &startPos)
virtual void	mouseReleaseEvent (QMouseEvent *event, const QPointF &startPos)
virtual void	mouseDoubleClickEvent (QMouseEvent *event, const QVariant &details)
virtual void	wheelEvent (QWheelEvent *event)
void	initializeParentPlot (QCustomPlot *parentPlot)
void	setParentLayerable (QCPLayerable *parentLayerable)
bool	moveToLayer (QCPLayer *layer, bool prepend)
void	applyAntialiasingHint (QCPPainter *painter, bool localAntialiased, QCP::AntialiasedElement overrideElement) const

Protected Attributes
QCPScatterStyle	mScatterStyle
int	mScatterSkip
LineStyle	mLineStyle
Protected Attributes inherited from QCPAbstractPlottable1D< QCPCurveData >
QSharedPointer< QCPDataContainer< QCPCurveData > >	mDataContainer
Protected Attributes inherited from QCPAbstractPlottable
QString	mName
bool	mAntialiasedFill
bool	mAntialiasedScatters
QPen	mPen
QBrush	mBrush
QPointer< QCPAxis >	mKeyAxis
QPointer< QCPAxis >	mValueAxis
QCP::SelectionType	mSelectable
QCPDataSelection	mSelection
QCPSelectionDecorator *	mSelectionDecorator
Protected Attributes inherited from QCPLayerable
bool	mVisible
QCustomPlot *	mParentPlot
QPointer< QCPLayerable >	mParentLayerable
QCPLayer *	mLayer
bool	mAntialiased

Friends
class	QCustomPlot
class	QCPLegend

Additional Inherited Members
Signals inherited from QCPAbstractPlottable
void	selectionChanged (bool selected)
void	selectionChanged (const QCPDataSelection &selection)
void	selectableChanged (QCP::SelectionType selectable)
Signals inherited from QCPLayerable
void	layerChanged (QCPLayer *newLayer)

Detailed Description

A plottable representing a parametric curve in a plot.

Unlike QCPGraph, plottables of this type may have multiple points with the same key coordinate, so their visual representation can have loops. This is realized by introducing a third coordinate t, which defines the order of the points described by the other two coordinates x and y.

To plot data, assign it with the setData or addData functions. Alternatively, you can also access and modify the curve's data via the data method, which returns a pointer to the internal QCPCurveDataContainer.

Gaps in the curve can be created by adding data points with NaN as key and value (qQNaN() or std::numeric_limits<double>::quiet_NaN()) in between the two data points that shall be separated.

Changing the appearance

The appearance of the curve is determined by the pen and the brush (setPen, setBrush).

Usage

Like all data representing objects in QCustomPlot, the QCPCurve is a plottable (QCPAbstractPlottable). So the plottable-interface of QCustomPlot applies (QCustomPlot::plottable, QCustomPlot::removePlottable, etc.)

Usually, you first create an instance:

which registers it with the QCustomPlot instance of the passed axes. Note that this QCustomPlot instance takes ownership of the plottable, so do not delete it manually but use QCustomPlot::removePlottable() instead. The newly created plottable can be modified, e.g.:

Member Enumeration Documentation

LineStyle

enum QCPCurve::LineStyle

Defines how the curve's line is represented visually in the plot. The line is drawn with the current pen of the curve (setPen).

See also

setLineStyle

Enumerator
lsNone	No line is drawn between data points (e.g. only scatters)
lsLine	Data points are connected with a straight line.

Constructor & Destructor Documentation

QCPCurve()

QCPCurve::QCPCurve ( QCPAxis * keyAxis, QCPAxis * valueAxis )

explicit

Constructs a curve which uses keyAxis as its key axis ("x") and valueAxis as its value axis ("y"). keyAxis and valueAxis must reside in the same QCustomPlot instance and not have the same orientation. If either of these restrictions is violated, a corresponding message is printed to the debug output (qDebug), the construction is not aborted, though.

The created QCPCurve is automatically registered with the QCustomPlot instance inferred from keyAxis. This QCustomPlot instance takes ownership of the QCPCurve, so do not delete it manually but use QCustomPlot::removePlottable() instead.

Member Function Documentation

addData() [1/4]

void QCPCurve::addData	(	const QVector< double > &	keys,
		const QVector< double > &	values )

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Adds the provided points in keys and values to the current data. The provided vectors should have equal length. Else, the number of added points will be the size of the smallest vector.

The t parameter of each data point will be set to the integer index of the respective key/value pair.

Alternatively, you can also access and modify the data directly via the data method, which returns a pointer to the internal data container.

addData() [2/4]

void QCPCurve::addData	(	const QVector< double > &	t,
		const QVector< double > &	keys,
		const QVector< double > &	values,
		bool	alreadySorted = false )

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Adds the provided points in t, keys and values to the current data. The provided vectors should have equal length. Else, the number of added points will be the size of the smallest vector.

If you can guarantee that the passed data points are sorted by keys in ascending order, you can set alreadySorted to true, to improve performance by saving a sorting run.

Alternatively, you can also access and modify the data directly via the data method, which returns a pointer to the internal data container.

addData() [3/4]

void QCPCurve::addData	(	double	key,
		double	value )

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Adds the provided data point as key and value to the current data.

The t parameter is generated automatically by increments of 1 for each point, starting at the highest t of previously existing data or 0, if the curve data is empty.

Alternatively, you can also access and modify the data directly via the data method, which returns a pointer to the internal data container.

addData() [4/4]

void QCPCurve::addData	(	double	t,
		double	key,
		double	value )

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts. Adds the provided data point as t, key and value to the current data.

Alternatively, you can also access and modify the data directly via the data method, which returns a pointer to the internal data container.

data()

QSharedPointer< QCPCurveDataContainer > QCPCurve::data ( ) const

inline

Returns a shared pointer to the internal data storage of type QCPCurveDataContainer. You may use it to directly manipulate the data, which may be more convenient and faster than using the regular setData or addData methods.

draw()

void QCPCurve::draw ( QCPPainter * painter )

protectedvirtual

Implements QCPAbstractPlottable.

drawLegendIcon()

void QCPCurve::drawLegendIcon ( QCPPainter * painter, const QRectF & rect ) const

protectedvirtual

Implements QCPAbstractPlottable.

getKeyRange()

QCPRange QCPCurve::getKeyRange ( bool & foundRange, QCP::SignDomain inSignDomain = QCP::sdBoth ) const

virtual

Returns the coordinate range that all data in this plottable span in the key axis dimension. For logarithmic plots, one can set inSignDomain to either QCP::sdNegative or QCP::sdPositive in order to restrict the returned range to that sign domain. E.g. when only negative range is wanted, set inSignDomain to QCP::sdNegative and all positive points will be ignored for range calculation. For no restriction, just set inSignDomain to QCP::sdBoth (default). foundRange is an output parameter that indicates whether a range could be found or not. If this is false, you shouldn't use the returned range (e.g. no points in data).

Note that foundRange is not the same as QCPRange::validRange, since the range returned by this function may have size zero (e.g. when there is only one data point). In this case foundRange would return true, but the returned range is not a valid range in terms of QCPRange::validRange.

See also

rescaleAxes, getValueRange

Implements QCPAbstractPlottable.

getValueRange()

QCPRange QCPCurve::getValueRange ( bool & foundRange, QCP::SignDomain inSignDomain = QCP::sdBoth, const QCPRange & inKeyRange = QCPRange() ) const

virtual

Returns the coordinate range that the data points in the specified key range (inKeyRange) span in the value axis dimension. For logarithmic plots, one can set inSignDomain to either QCP::sdNegative or QCP::sdPositive in order to restrict the returned range to that sign domain. E.g. when only negative range is wanted, set inSignDomain to QCP::sdNegative and all positive points will be ignored for range calculation. For no restriction, just set inSignDomain to QCP::sdBoth (default). foundRange is an output parameter that indicates whether a range could be found or not. If this is false, you shouldn't use the returned range (e.g. no points in data).

If inKeyRange has both lower and upper bound set to zero (is equal to QCPRange()), all data points are considered, without any restriction on the keys.

Note that foundRange is not the same as QCPRange::validRange, since the range returned by this function may have size zero (e.g. when there is only one data point). In this case foundRange would return true, but the returned range is not a valid range in terms of QCPRange::validRange.

See also

rescaleAxes, getKeyRange

Implements QCPAbstractPlottable.

selectTest()

double QCPCurve::selectTest ( const QPointF & pos, bool onlySelectable, QVariant * details = nullptr ) const

virtual

Implements a selectTest specific to this plottable's point geometry.

If details is not 0, it will be set to a QCPDataSelection, describing the closest data point to pos.

\seebaseclassmethod QCPAbstractPlottable::selectTest

Reimplemented from QCPAbstractPlottable1D< QCPCurveData >.

setData() [1/3]

void QCPCurve::setData	(	const QVector< double > &	keys,
		const QVector< double > &	values )

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Replaces the current data with the provided points in keys and values. The provided vectors should have equal length. Else, the number of added points will be the size of the smallest vector.

The t parameter of each data point will be set to the integer index of the respective key/value pair.

See also

addData

setData() [2/3]

void QCPCurve::setData	(	const QVector< double > &	t,
		const QVector< double > &	keys,
		const QVector< double > &	values,
		bool	alreadySorted = false )

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Replaces the current data with the provided points in t, keys and values. The provided vectors should have equal length. Else, the number of added points will be the size of the smallest vector.

If you can guarantee that the passed data points are sorted by t in ascending order, you can set alreadySorted to true, to improve performance by saving a sorting run.

See also

addData

setData() [3/3]

void QCPCurve::setData

(

QSharedPointer< QCPCurveDataContainer >

data

)

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Replaces the current data container with the provided data container.

Since a QSharedPointer is used, multiple QCPCurves may share the same data container safely. Modifying the data in the container will then affect all curves that share the container. Sharing can be achieved by simply exchanging the data containers wrapped in shared pointers:

If you do not wish to share containers, but create a copy from an existing container, rather use the QCPDataContainer<DataType>::set method on the curve's data container directly:

See also

addData

setLineStyle()

void QCPCurve::setLineStyle

(

QCPCurve::LineStyle

style

)

Sets how the single data points are connected in the plot or how they are represented visually apart from the scatter symbol. For scatter-only plots, set style to lsNone and setScatterStyle to the desired scatter style.

See also

setScatterStyle

setScatterSkip()

void QCPCurve::setScatterSkip

(

int

skip

)

If scatters are displayed (scatter style not QCPScatterStyle::ssNone), skip number of scatter points are skipped/not drawn after every drawn scatter point.

This can be used to make the data appear sparser while for example still having a smooth line, and to improve performance for very high density plots.

If skip is set to 0 (default), all scatter points are drawn.

See also

setScatterStyle

setScatterStyle()

void QCPCurve::setScatterStyle

(

const QCPScatterStyle &

style

)

Sets the visual appearance of single data points in the plot. If set to QCPScatterStyle::ssNone, no scatter points are drawn (e.g. for line-only plots with appropriate line style).

See also

QCPScatterStyle, setLineStyle

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

• qcustomplot.h
• qcustomplot.cpp