A plottable representing a graph in a plot. More...

Inheritance diagram for QCPGraph:

Public Types
enum	LineStyle { lsNone , lsLine , lsStepLeft , lsStepRight , lsStepCenter , lsImpulse }
	Defines how the graph's line is represented visually in the plot. More...

Public Member Functions
	QCPGraph (QCPAxis keyAxis, QCPAxis valueAxis)
	Constructs a graph which uses keyAxis as its key axis ("x") and valueAxis as its value axis ("y").

QSharedPointer< QCPGraphDataContainer >	data () const
	Returns a shared pointer to the internal data storage of type QCPGraphDataContainer.

LineStyle	lineStyle () const

QCPScatterStyle	scatterStyle () const

int	scatterSkip () const

QCPGraph *	channelFillGraph () const

bool	adaptiveSampling () const

void	setData (QSharedPointer< QCPGraphDataContainer > 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.

void	setData (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 keys and values.

void	setLineStyle (LineStyle ls)
	Sets how the single data points are connected in the plot.

void	setScatterStyle (const QCPScatterStyle &style)
	Sets the visual appearance of single data points in the plot.

void	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.

void	setChannelFillGraph (QCPGraph *targetGraph)
	Sets the target graph for filling the area between this graph and targetGraph with the current brush (setBrush).

void	setAdaptiveSampling (bool enabled)
	Sets whether adaptive sampling shall be used when plotting this graph.

void	addData (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 keys and values to the current data.

void	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.

virtual double	selectTest (const QPointF &pos, bool onlySelectable, QVariant *details=0) const Q_DECL_OVERRIDE
	Implements a point-selection algorithm assuming the data (accessed via the 1D data interface) is point-like.

virtual QCPRange	getKeyRange (bool &foundRange, QCP::SignDomain inSignDomain=QCP::sdBoth) const Q_DECL_OVERRIDE
	Returns the coordinate range that all data in this plottable span in the key axis dimension.

virtual QCPRange	getValueRange (bool &foundRange, QCP::SignDomain inSignDomain=QCP::sdBoth, const QCPRange &inKeyRange=QCPRange()) const Q_DECL_OVERRIDE
	Returns the coordinate range that the data points in the specified key range (inKeyRange) span in the value axis dimension.

Public Member Functions inherited from QCPAbstractPlottable1D< QCPGraphData >
	QCPAbstractPlottable1D (QCPAxis keyAxis, QCPAxis valueAxis)
	Forwards keyAxis and valueAxis to the QCPAbstractPlottable constructor and allocates the mDataContainer.

virtual int	dataCount () const Q_DECL_OVERRIDE
	Returns the number of data points of the plottable.

virtual double	dataMainKey (int index) const Q_DECL_OVERRIDE
	Returns the main key of the data point at the given index.

virtual double	dataSortKey (int index) const Q_DECL_OVERRIDE
	Returns the sort key of the data point at the given index.

virtual double	dataMainValue (int index) const Q_DECL_OVERRIDE
	Returns the main value of the data point at the given index.

virtual QCPRange	dataValueRange (int index) const Q_DECL_OVERRIDE
	Returns the value range of the data point at the given index.

virtual QPointF	dataPixelPosition (int index) const Q_DECL_OVERRIDE
	Returns the pixel position on the widget surface at which the data point at the given index appears.

virtual bool	sortKeyIsMainKey () const Q_DECL_OVERRIDE
	Returns whether the sort key (dataSortKey) is identical to the main key (dataMainKey).

virtual QCPDataSelection	selectTestRect (const QRectF &rect, bool onlySelectable) const Q_DECL_OVERRIDE
	Implements a rect-selection algorithm assuming the data (accessed via the 1D data interface) is point-like.

virtual int	findBegin (double sortKey, bool expandedRange=true) const Q_DECL_OVERRIDE
	Returns the index of the data point with a (sort-)key that is equal to, just below, or just above sortKey.

virtual int	findEnd (double sortKey, bool expandedRange=true) const Q_DECL_OVERRIDE
	Returns the index one after the data point with a (sort-)key that is equal to, just above, or just below sortKey.

virtual double	selectTest (const QPointF &pos, bool onlySelectable, QVariant *details=0) const Q_DECL_OVERRIDE
	Implements a point-selection algorithm assuming the data (accessed via the 1D data interface) is point-like.

virtual QCPPlottableInterface1D *	interface1D () Q_DECL_OVERRIDE
	Returns a QCPPlottableInterface1D pointer to this plottable, providing access to its 1D interface.

Public Member Functions inherited from QCPAbstractPlottable
	QCPAbstractPlottable (QCPAxis keyAxis, QCPAxis valueAxis)
	Constructs an abstract plottable which uses keyAxis as its key axis ("x") and valueAxis as its value axis ("y").

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
	Returns true if there are any data points of the plottable currently selected.

QCPDataSelection	selection () const
	Returns a QCPDataSelection encompassing all the data points that are currently selected on this plottable.

QCPSelectionDecorator *	selectionDecorator () const
	Provides access to the selection decorator of this plottable.

void	setName (const QString &name)
	The name is the textual representation of this plottable as it is displayed in the legend (QCPLegend).

void	setAntialiasedFill (bool enabled)
	Sets whether fills of this plottable are drawn antialiased or not.

void	setAntialiasedScatters (bool enabled)
	Sets whether the scatter symbols of this plottable are drawn antialiased or not.

void	setPen (const QPen &pen)
	The pen is used to draw basic lines that make up the plottable representation in the plot.

void	setBrush (const QBrush &brush)
	The brush is used to draw basic fills of the plottable representation in the plot.

void	setKeyAxis (QCPAxis *axis)
	The key axis of a plottable can be set to any axis of a QCustomPlot, as long as it is orthogonal to the plottable's value axis.

void	setValueAxis (QCPAxis *axis)
	The value axis of a plottable can be set to any axis of a QCustomPlot, as long as it is orthogonal to the plottable's key axis.

Q_SLOT void	setSelectable (QCP::SelectionType selectable)
	Sets whether and to which granularity this plottable can be selected.

Q_SLOT void	setSelection (QCPDataSelection selection)
	Sets which data ranges of this plottable are selected.

void	setSelectionDecorator (QCPSelectionDecorator *decorator)
	Use this method to set an own QCPSelectionDecorator (subclass) instance.

virtual double	selectTest (const QPointF &pos, bool onlySelectable, QVariant *details=0) const =0
	This function is used to decide whether a click hits a layerable object or not.

virtual QCPPlottableInterface1D *	interface1D ()
	If this plottable is a one-dimensional plottable, i.e.

virtual QCPRange	getKeyRange (bool &foundRange, QCP::SignDomain inSignDomain=QCP::sdBoth) const =0
	Returns the coordinate range that all data in this plottable span in the key axis dimension.

virtual QCPRange	getValueRange (bool &foundRange, QCP::SignDomain inSignDomain=QCP::sdBoth, const QCPRange &inKeyRange=QCPRange()) const =0
	Returns the coordinate range that the data points in the specified key range (inKeyRange) span in the value axis dimension.

void	coordsToPixels (double key, double value, double &x, double &y) const
	Convenience function for transforming a key/value pair to pixels on the QCustomPlot surface, taking the orientations of the axes associated with this plottable into account (e.g.

const QPointF	coordsToPixels (double key, double value) const
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.Transforms the given key and value to pixel coordinates and returns them in a QPointF.

void	pixelsToCoords (double x, double y, double &key, double &value) const
	Convenience function for transforming a x/y pixel pair on the QCustomPlot surface to plot coordinates, taking the orientations of the axes associated with this plottable into account (e.g.

void	pixelsToCoords (const QPointF &pixelPos, double &key, double &value) const
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.Returns the pixel input pixelPos as plot coordinates key and value.

void	rescaleAxes (bool onlyEnlarge=false) const
	Rescales the key and value axes associated with this plottable to contain all displayed data, so the whole plottable is visible.

void	rescaleKeyAxis (bool onlyEnlarge=false) const
	Rescales the key axis of the plottable so the whole plottable is visible.

void	rescaleValueAxis (bool onlyEnlarge=false, bool inKeyRange=false) const
	Rescales the value axis of the plottable so the whole plottable is visible.

bool	addToLegend (QCPLegend *legend)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.Adds this plottable to the specified legend.

bool	addToLegend ()
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.Adds this plottable to the legend of the parent QCustomPlot (QCustomPlot::legend).

bool	removeFromLegend (QCPLegend *legend) const
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.Removes the plottable from the specifed legend.

bool	removeFromLegend () const
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.Removes the plottable from the legend of the parent QCustomPlot.

Public Member Functions inherited from QCPLayerable
	QCPLayerable (QCustomPlot plot, QString targetLayer=QString(), QCPLayerable parentLayerable=0)
	Creates a new QCPLayerable instance.

bool	visible () const

QCustomPlot *	parentPlot () const

QCPLayerable *	parentLayerable () const
	Returns the parent layerable of this layerable.

QCPLayer *	layer () const

bool	antialiased () const

void	setVisible (bool on)
	Sets the visibility of this layerable object.

Q_SLOT bool	setLayer (QCPLayer *layer)
	Sets the layer of this layerable object.

bool	setLayer (const QString &layerName)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts. Sets the layer of this layerable object by name.

void	setAntialiased (bool enabled)
	Sets whether this object will be drawn antialiased or not.

virtual double	selectTest (const QPointF &pos, bool onlySelectable, QVariant *details=0) const
	This function is used to decide whether a click hits a layerable object or not.

bool	realVisibility () const
	Returns whether this layerable is visible, taking the visibility of the layerable parent and the visibility of this layerable's layer into account.

virtual int	dataCount () const =0
	Returns the number of data points of the plottable.

virtual double	dataMainKey (int index) const =0
	Returns the main key of the data point at the given index.

virtual double	dataSortKey (int index) const =0
	Returns the sort key of the data point at the given index.

virtual double	dataMainValue (int index) const =0
	Returns the main value of the data point at the given index.

virtual QCPRange	dataValueRange (int index) const =0
	Returns the value range of the data point at the given index.

virtual QPointF	dataPixelPosition (int index) const =0
	Returns the pixel position on the widget surface at which the data point at the given index appears.

virtual bool	sortKeyIsMainKey () const =0
	Returns whether the sort key (dataSortKey) is identical to the main key (dataMainKey).

virtual QCPDataSelection	selectTestRect (const QRectF &rect, bool onlySelectable) const =0
	Returns a data selection containing all the data points of this plottable which are contained (or hit by) rect.

virtual int	findBegin (double sortKey, bool expandedRange=true) const =0
	Returns the index of the data point with a (sort-)key that is equal to, just below, or just above sortKey.

virtual int	findEnd (double sortKey, bool expandedRange=true) const =0
	Returns the index one after the data point with a (sort-)key that is equal to, just above, or just below sortKey.

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	drawFill (QCPPainter painter, QVector< QPointF > lines) const

virtual void	drawScatterPlot (QCPPainter *painter, const QVector< QPointF > &scatters, const QCPScatterStyle &style) const

virtual void	drawLinePlot (QCPPainter *painter, const QVector< QPointF > &lines) const

virtual void	drawImpulsePlot (QCPPainter *painter, const QVector< QPointF > &lines) const

virtual void	getOptimizedLineData (QVector< QCPGraphData > *lineData, const QCPGraphDataContainer::const_iterator &begin, const QCPGraphDataContainer::const_iterator &end) const

virtual void	getOptimizedScatterData (QVector< QCPGraphData > *scatterData, QCPGraphDataContainer::const_iterator begin, QCPGraphDataContainer::const_iterator end) const

void	getVisibleDataBounds (QCPGraphDataContainer::const_iterator &begin, QCPGraphDataContainer::const_iterator &end, const QCPDataRange &rangeRestriction) const
	This method outputs the currently visible data range via begin and end.

void	getLines (QVector< QPointF > *lines, const QCPDataRange &dataRange) const

void	getScatters (QVector< QPointF > *scatters, const QCPDataRange &dataRange) const

QVector< QPointF >	dataToLines (const QVector< QCPGraphData > &data) const

QVector< QPointF >	dataToStepLeftLines (const QVector< QCPGraphData > &data) const

QVector< QPointF >	dataToStepRightLines (const QVector< QCPGraphData > &data) const

QVector< QPointF >	dataToStepCenterLines (const QVector< QCPGraphData > &data) const

QVector< QPointF >	dataToImpulseLines (const QVector< QCPGraphData > &data) const

QVector< QCPDataRange >	getNonNanSegments (const QVector< QPointF > *lineData, Qt::Orientation keyOrientation) const

QVector< QPair< QCPDataRange, QCPDataRange > >	getOverlappingSegments (QVector< QCPDataRange > thisSegments, const QVector< QPointF > thisData, QVector< QCPDataRange > otherSegments, const QVector< QPointF > otherData) const

bool	segmentsIntersect (double aLower, double aUpper, double bLower, double bUpper, int &bPrecedence) const

QPointF	getFillBasePoint (QPointF matchingDataPoint) const

const QPolygonF	getFillPolygon (const QVector< QPointF > *lineData, QCPDataRange segment) const

const QPolygonF	getChannelFillPolygon (const QVector< QPointF > lineData, QCPDataRange thisSegment, const QVector< QPointF > otherData, QCPDataRange otherSegment) const

int	findIndexBelowX (const QVector< QPointF > *data, double x) const

int	findIndexAboveX (const QVector< QPointF > *data, double x) const

int	findIndexBelowY (const QVector< QPointF > *data, double y) const

int	findIndexAboveY (const QVector< QPointF > *data, double y) const

double	pointDistance (const QPointF &pixelPoint, QCPGraphDataContainer::const_iterator &closestData) const

Protected Member Functions inherited from QCPAbstractPlottable1D< QCPGraphData >
void	getDataSegments (QList< QCPDataRange > &selectedSegments, QList< QCPDataRange > &unselectedSegments) const
	Splits all data into selected and unselected segments and outputs them via selectedSegments and unselectedSegments, respectively.

void	drawPolyline (QCPPainter *painter, const QVector< QPointF > &lineData) const
	A helper method which draws a line with the passed painter, according to the pixel data in lineData.

Protected Member Functions inherited from QCPAbstractPlottable
virtual QRect	clipRect () const Q_DECL_OVERRIDE

virtual void	draw (QCPPainter *painter) Q_DECL_OVERRIDE=0

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

virtual void	drawLegendIcon (QCPPainter *painter, const QRectF &rect) const =0

void	applyFillAntialiasingHint (QCPPainter *painter) const

void	applyScattersAntialiasingHint (QCPPainter *painter) const

Protected Member Functions inherited from QCPLayerable
virtual void	parentPlotInitialized (QCustomPlot *parentPlot)

virtual QCP::Interaction	selectionCategory () const

virtual QRect	clipRect () const

virtual void	applyDefaultAntialiasingHint (QCPPainter *painter) const =0

virtual void	draw (QCPPainter *painter)=0

virtual void	selectEvent (QMouseEvent event, bool additive, const QVariant &details, bool selectionStateChanged)

virtual void	deselectEvent (bool *selectionStateChanged)

virtual void	mousePressEvent (QMouseEvent *event, const QVariant &details)
	This event gets called when the user presses a mouse button while the cursor is over the layerable.

virtual void	mouseMoveEvent (QMouseEvent *event, const QPointF &startPos)
	This event gets called when the user moves the mouse while holding a mouse button, after this layerable has become the mouse grabber by accepting the preceding mousePressEvent.

virtual void	mouseReleaseEvent (QMouseEvent *event, const QPointF &startPos)
	This event gets called when the user releases the mouse button, after this layerable has become the mouse grabber by accepting the preceding mousePressEvent.

virtual void	mouseDoubleClickEvent (QMouseEvent *event, const QVariant &details)
	This event gets called when the user presses the mouse button a second time in a double-click, while the cursor is over the layerable.

virtual void	wheelEvent (QWheelEvent *event)
	This event gets called when the user turns the mouse scroll wheel while the cursor is over the layerable.

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
LineStyle	mLineStyle

QCPScatterStyle	mScatterStyle

int	mScatterSkip

QPointer< QCPGraph >	mChannelFillGraph

bool	mAdaptiveSampling

Protected Attributes inherited from QCPAbstractPlottable1D< QCPGraphData >
QSharedPointer< QCPDataContainer< QCPGraphData > >	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)
	This signal is emitted when the selection state of this plottable has changed, either by user interaction or by a direct call to setSelection.

void	selectionChanged (const QCPDataSelection &selection)
	This signal is emitted when the selection state of this plottable has changed, either by user interaction or by a direct call to setSelection.

void	selectableChanged (QCP::SelectionType selectable)
	This signal is emitted when the selectability of this plottable has changed.

Signals inherited from QCPLayerable
void	layerChanged (QCPLayer *newLayer)
	This signal is emitted when the layer of this layerable changes, i.e.

Detailed Description

A plottable representing a graph in a plot.

Usually you create new graphs by calling QCustomPlot::addGraph. The resulting instance can be accessed via QCustomPlot::graph.

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

Graphs are used to display single-valued data. Single-valued means that there should only be one data point per unique key coordinate. In other words, the graph can't have loops. If you do want to plot non-single-valued curves, rather use the QCPCurve plottable.

Gaps in the graph line can be created by adding data points with NaN as 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 graph is mainly determined by the line style, scatter style, brush and pen of the graph (setLineStyle, setScatterStyle, setBrush, setPen).

Filling under or between graphs

QCPGraph knows two types of fills: Normal graph fills towards the zero-value-line parallel to the key axis of the graph, and fills between two graphs, called channel fills. To enable a fill, just set a brush with setBrush which is neither Qt::NoBrush nor fully transparent.

By default, a normal fill towards the zero-value-line will be drawn. To set up a channel fill between this graph and another one, call setChannelFillGraph with the other graph as parameter.

See also: QCustomPlot::addGraph, QCustomPlot::graph

Member Enumeration Documentation

◆ LineStyle

enum QCPGraph::LineStyle

Defines how the graph's line is represented visually in the plot.

The line is drawn with the current pen of the graph (setPen).

See also: setLineStyle

Enumerator
lsNone	data points are not connected with any lines (e.g. data only represented with symbols according to the scatter style, see setScatterStyle)
lsLine	data points are connected by a straight line
lsStepLeft	line is drawn as steps where the step height is the value of the left data point
lsStepRight	line is drawn as steps where the step height is the value of the right data point
lsStepCenter	line is drawn as steps where the step is in between two data points
lsImpulse	each data point is represented by a line parallel to the value axis, which reaches from the data point to the zero-value-line

Constructor & Destructor Documentation

◆ QCPGraph()

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

explicit

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

To directly create a graph inside a plot, you can also use the simpler QCustomPlot::addGraph function.

Member Function Documentation

◆ addData() [1/2]

void QCPGraph::addData	(	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 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() [2/2]

void QCPGraph::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.

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< QCPGraphDataContainer > QCPGraph::data ( ) const

inline

Returns a shared pointer to the internal data storage of type QCPGraphDataContainer.

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 QCPGraph::draw ( QCPPainter * painter )

protectedvirtual

Implements QCPAbstractPlottable.

◆ drawLegendIcon()

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

protectedvirtual

Implements QCPAbstractPlottable.

◆ getKeyRange()

QCPRange QCPGraph::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 QCPGraph::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.

◆ getVisibleDataBounds()

void QCPGraph::getVisibleDataBounds	(	QCPGraphDataContainer::const_iterator &	begin,
		QCPGraphDataContainer::const_iterator &	end,
		const QCPDataRange &	rangeRestriction
	)		const

protected

This method outputs the currently visible data range via begin and end.

The returned range will also never exceed rangeRestriction.

This method takes into account that the drawing of data lines at the axis rect border always requires the points just outside the visible axis range. So begin and end may actually indicate a range that contains one additional data point to the left and right of the visible axis range.

◆ selectTest()

double QCPGraph::selectTest	(	const QPointF &	pos,
		bool	onlySelectable,
		QVariant *	details = `0`
	)		const

virtual

Implements a point-selection algorithm assuming the data (accessed via the 1D data interface) is point-like.

Most subclasses will want to reimplement this method again, to provide a more accurate hit test based on the true data visualization geometry.

\seebaseclassmethod

Reimplemented from QCPAbstractPlottable1D< QCPGraphData >.

◆ setAdaptiveSampling()

void QCPGraph::setAdaptiveSampling ( bool enabled )

Sets whether adaptive sampling shall be used when plotting this graph.

QCustomPlot's adaptive sampling technique can drastically improve the replot performance for graphs with a larger number of points (e.g. above 10,000), without notably changing the appearance of the graph.

By default, adaptive sampling is enabled. Even if enabled, QCustomPlot decides whether adaptive sampling shall actually be used on a per-graph basis. So leaving adaptive sampling enabled has no disadvantage in almost all cases.

A line plot of 500,000 points without and with adaptive sampling

As can be seen, line plots experience no visual degradation from adaptive sampling. Outliers are reproduced reliably, as well as the overall shape of the data set. The replot time reduces dramatically though. This allows QCustomPlot to display large amounts of data in realtime.

A scatter plot of 100,000 points without and with adaptive sampling

Care must be taken when using high-density scatter plots in combination with adaptive sampling. The adaptive sampling algorithm treats scatter plots more carefully than line plots which still gives a significant reduction of replot times, but not quite as much as for line plots. This is because scatter plots inherently need more data points to be preserved in order to still resemble the original, non-adaptive-sampling plot. As shown above, the results still aren't quite identical, as banding occurs for the outer data points. This is in fact intentional, such that the boundaries of the data cloud stay visible to the viewer. How strong the banding appears, depends on the point density, i.e. the number of points in the plot.

For some situations with scatter plots it might thus be desirable to manually turn adaptive sampling off. For example, when saving the plot to disk. This can be achieved by setting enabled to false before issuing a command like QCustomPlot::savePng, and setting enabled back to true afterwards.

◆ setChannelFillGraph()

void QCPGraph::setChannelFillGraph ( QCPGraph * targetGraph )

Sets the target graph for filling the area between this graph and targetGraph with the current brush (setBrush).

When targetGraph is set to 0, a normal graph fill to the zero-value-line will be shown. To disable any filling, set the brush to Qt::NoBrush.

See also: setBrush

◆ setData() [1/2]

void QCPGraph::setData	(	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 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 keys in ascending order, you can set alreadySorted to true, to improve performance by saving a sorting run.

See also: addData

◆ setData() [2/2]

void QCPGraph::setData ( QSharedPointer< QCPGraphDataContainer > 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 QCPGraphs may share the same data container safely. Modifying the data in the container will then affect all graphs 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 graph's data container directly:

See also: addData

◆ setLineStyle()

void QCPGraph::setLineStyle ( LineStyle ls )

Sets how the single data points are connected in the plot.

For scatter-only plots, set ls to lsNone and setScatterStyle to the desired scatter style.

See also: setScatterStyle

◆ setScatterSkip()

void QCPGraph::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 QCPGraph::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

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

qcustomplot.h
qcustomplot.cpp

Public Types

Public Member Functions

Protected Member Functions

Protected Attributes

Friends

Additional Inherited Members

Detailed Description

Changing the appearance

Filling under or between graphs

Member Enumeration Documentation

◆ LineStyle

Constructor & Destructor Documentation

◆ QCPGraph()

Member Function Documentation

◆ addData() [1/2]

◆ addData() [2/2]

◆ data()

◆ draw()

◆ drawLegendIcon()

◆ getKeyRange()

◆ getValueRange()

◆ getVisibleDataBounds()

◆ selectTest()

◆ setAdaptiveSampling()

◆ setChannelFillGraph()

◆ setData() [1/2]

◆ setData() [2/2]

◆ setLineStyle()

◆ setScatterSkip()

◆ setScatterStyle()