#include <qwt_plot_histogram.h>

Inherits QwtPlotSeriesItem< QwtIntervalSample >.

Public Types
enum	HistogramStyle { Outline, Columns, Lines, UserStyle = 100 }
enum	ItemAttribute { Legend = 0x01, AutoScale = 0x02 }
typedef QFlags< ItemAttribute >	ItemAttributes
enum	RenderHint { RenderAntialiased = 1 }
typedef QFlags< RenderHint >	RenderHints
enum	RttiValues { Rtti_PlotItem = 0, Rtti_PlotGrid, Rtti_PlotScale, Rtti_PlotMarker, Rtti_PlotCurve, Rtti_PlotSpectroCurve, Rtti_PlotIntervalCurve, Rtti_PlotHistogram, Rtti_PlotSpectrogram, Rtti_PlotSVG, Rtti_PlotUserItem = 1000 }
Public Member Functions
void	attach (QwtPlot *plot)
double	baseline () const
virtual QRectF	boundingRect () const
const QBrush &	brush () const
QwtSeriesData < QwtIntervalSample > *	data ()
const QwtSeriesData < QwtIntervalSample > *	data () const
size_t	dataSize () const
void	detach ()
virtual void	draw (QPainter *p, const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRectF &) const
virtual void	drawLegendIdentifier (QPainter *, const QRectF &) const
virtual void	drawSeries (QPainter *p, const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRectF &canvasRect, int from, int to) const
void	hide ()
bool	isVisible () const
virtual void	itemChanged ()
virtual QWidget *	legendItem () const
Qt::Orientation	orientation () const
QRectF	paintRect (const QwtScaleMap &, const QwtScaleMap &) const
const QPen &	pen () const
QwtPlot *	plot () const
	QwtPlotHistogram (const QString &title=QString::null)
	QwtPlotHistogram (const QwtText &title)
virtual int	rtti () const
QwtIntervalSample	sample (int index) const
QRectF	scaleRect (const QwtScaleMap &, const QwtScaleMap &) const
void	setAxes (int xAxis, int yAxis)
void	setBaseline (double reference)
void	setBrush (const QBrush &)
void	setData (QwtSeriesData< QwtIntervalSample > *)
void	setItemAttribute (ItemAttribute, bool on=true)
void	setOrientation (Qt::Orientation)
void	setPen (const QPen &)
void	setRenderHint (RenderHint, bool on=true)
void	setSamples (const QVector< QwtIntervalSample > &)
void	setStyle (HistogramStyle style)
void	setSymbol (const QwtColumnSymbol *)
void	setTitle (const QString &title)
void	setTitle (const QwtText &title)
virtual void	setVisible (bool)
void	setXAxis (int axis)
void	setYAxis (int axis)
void	setZ (double z)
void	show ()
HistogramStyle	style () const
const QwtColumnSymbol *	symbol () const
bool	testItemAttribute (ItemAttribute) const
bool	testRenderHint (RenderHint) const
const QwtText &	title () const
virtual void	updateLegend (QwtLegend *) const
virtual void	updateScaleDiv (const QwtScaleDiv &, const QwtScaleDiv &)
int	xAxis () const
int	yAxis () const
double	z () const
virtual	~QwtPlotHistogram ()
Protected Member Functions
virtual QwtColumnRect	columnRect (const QwtIntervalSample &, const QwtScaleMap &, const QwtScaleMap &) const
virtual void	drawColumn (QPainter *, const QwtColumnRect &, const QwtIntervalSample &) const
void	drawColumns (QPainter *, const QwtScaleMap &xMap, const QwtScaleMap &yMap, int from, int to) const
void	drawLines (QPainter *, const QwtScaleMap &xMap, const QwtScaleMap &yMap, int from, int to) const
void	drawOutline (QPainter *, const QwtScaleMap &xMap, const QwtScaleMap &yMap, int from, int to) const
Protected Attributes
QwtSeriesData < QwtIntervalSample > *	d_series

Detailed Description

QwtPlotHistogram represents a series of samples, where an interval is associated with a value ( $y = f([x1,x2])$ ).

The representation depends on the style() and an optional symbol() that is displayed for each interval.

Note:: The term "histogram" is used in a different way in the areas of digital image processing and statistics. Wikipedia introduces the terms "image histogram" and "color histogram" to avoid confusions. While "image histograms" can be displayed by a QwtPlotCurve there is no applicable plot item for a "color histogram" yet.

Member Typedef Documentation

typedef QFlags<ItemAttribute> QwtPlotItem::ItemAttributes [inherited]

Plot Item Attributes.

typedef QFlags<RenderHint> QwtPlotItem::RenderHints [inherited]

Render hints.

Member Enumeration Documentation

enum QwtPlotHistogram::HistogramStyle

Histogram styles. The default style is QwtPlotHistogram::Columns.

See also:: setStyle(), style(), setSymbol(), symbol(), setBaseline()

Enumerator:

Outline	Draw an outline around the area, that is build by all intervals using the pen() and fill it with the brush(). The outline style requires, that the intervals are in increasing order and not overlapping.
Columns	Draw a column for each interval. When a symbol() has been set the symbol is used otherwise the column is displayed as plain rectangle using pen() and brush().
Lines	Draw a simple line using the pen() for each interval.
UserStyle	Styles >= UserStyle are reserved for derived classes that overload drawSeries() with additional application specific ways to display a histogram.

enum QwtPlotItem::ItemAttribute [inherited]

Plot Item Attributes

See also:: setItemAttribute(), testItemAttribute()

Enumerator:

Legend	The item is represented on the legend.
AutoScale	The boundingRect() of the item is included in the autoscaling calculation.

enum QwtPlotItem::RenderHint [inherited]

Render hints.

Enumerator:

RenderAntialiased

Enable antialiasing.

enum QwtPlotItem::RttiValues [inherited]

Runtime type information.

RttiValues is used to cast plot items, without having to enable runtime type information of the compiler.

Enumerator:

Rtti_PlotItem	Unspecific value, that can be used, when it doesn't matter.
Rtti_PlotGrid	For QwtPlotGrid.
Rtti_PlotScale	For QwtPlotScaleItem.
Rtti_PlotMarker	For QwtPlotMarker.
Rtti_PlotCurve	For QwtPlotCurve.
Rtti_PlotSpectroCurve	For QwtPlotSpectroCurve.
Rtti_PlotIntervalCurve	For QwtPlotIntervalCurve.
Rtti_PlotHistogram	For QwtPlotHistogram.
Rtti_PlotSpectrogram	For QwtPlotSpectrogram.
Rtti_PlotSVG	For QwtPlotSvgItem.
Rtti_PlotUserItem	Values >= Rtti_PlotUserItem are reserved for plot items not implemented in the Qwt library.

Constructor & Destructor Documentation

QwtPlotHistogram::QwtPlotHistogram ( const QString & title = QString::null ) [explicit]

Constructor

Parameters:

title Title of the histogram.

QwtPlotHistogram::QwtPlotHistogram ( const QwtText & title ) [explicit]

Constructor

Parameters:

title Title of the histogram.

QwtPlotHistogram::~QwtPlotHistogram ( ) [virtual]

Destructor.

Member Function Documentation

void QwtPlotItem::attach ( QwtPlot * plot ) [inherited]

Attach the item to a plot.

This method will attach a QwtPlotItem to the QwtPlot argument. It will first detach the QwtPlotItem from any plot from a previous call to attach (if necessary). If a NULL argument is passed, it will detach from any QwtPlot it was attached to.

Parameters:

plot	Plot widget

See also:: detach()

double QwtPlotHistogram::baseline ( ) const

Returns:: Value of the baseline

See also:: setBaseline()

QRectF QwtPlotHistogram::boundingRect ( ) const [virtual]

Returns:: Bounding rectangle of all samples. For an empty series the rectangle is invalid.

Reimplemented from QwtPlotSeriesItem< QwtIntervalSample >.

const QBrush & QwtPlotHistogram::brush ( ) const

Returns:: Brush used in a style() depending way.

See also:: setPen(), brush()

QwtColumnRect QwtPlotHistogram::columnRect	(	const QwtIntervalSample &	sample,
		const QwtScaleMap &	xMap,
		const QwtScaleMap &	yMap
	)		const `[protected, virtual]`

Calculate the area that is covered by a sample

Parameters:

sample	Sample
xMap	Maps x-values into pixel coordinates.
yMap	Maps y-values into pixel coordinates.

Returns:: Rectangle, that is covered by a sample

void QwtPlotItem::detach ( ) [inherited]

This method detaches a QwtPlotItem from any QwtPlot it has been associated with.

detach() is equivalent to calling attach( NULL )

See also:: attach()

void QwtPlotAbstractSeriesItem::draw	(	QPainter *	painter,
		const QwtScaleMap &	xMap,
		const QwtScaleMap &	yMap,
		const QRectF &	canvasRect
	)		const `[virtual, inherited]`

Draw the complete series.

Parameters:

painter	Painter
xMap	Maps x-values into pixel coordinates.
yMap	Maps y-values into pixel coordinates.
canvasRect	Contents rect of the canvas

Implements QwtPlotItem.

void QwtPlotHistogram::drawColumn	(	QPainter *	painter,
		const QwtColumnRect &	rect,
		const QwtIntervalSample &	sample
	)		const `[protected, virtual]`

Draw a column for a sample in Columns style().

When a symbol() has been set the symbol is used otherwise the column is displayed as plain rectangle using pen() and brush().

Parameters:

painter	Painter
rect	Rectangle where to paint the column in paint device coordinates
sample	Sample to be displayed

Note:: In applications, where different intervals need to be displayed in a different way ( f.e different colors or even using differnt symbols) it is recommended to overload drawColumn().

void QwtPlotHistogram::drawColumns	(	QPainter *	painter,
		const QwtScaleMap &	xMap,
		const QwtScaleMap &	yMap,
		int	from,
		int	to
	)		const `[protected]`

Draw a histogram in Columns style()

Parameters:

painter	Painter
xMap	Maps x-values into pixel coordinates.
yMap	Maps y-values into pixel coordinates.
from	Index of the first sample to be painted
to	Index of the last sample to be painted. If to < 0 the histogram will be painted to its last point.

See also:: setStyle(), style(), setSymbol(), drawColumn()

void QwtPlotHistogram::drawLegendIdentifier	(	QPainter *	painter,
		const QRectF &	rect
	)		const `[virtual]`

Draw a plain rectangle without pen using the brush() as identifier

Parameters:

painter	Painter
rect	Bounding rectangle for the identifier

Reimplemented from QwtLegendItemManager.

void QwtPlotHistogram::drawLines	(	QPainter *	painter,
		const QwtScaleMap &	xMap,
		const QwtScaleMap &	yMap,
		int	from,
		int	to
	)		const `[protected]`

Draw a histogram in Lines style()

Parameters:

painter	Painter
xMap	Maps x-values into pixel coordinates.
yMap	Maps y-values into pixel coordinates.
from	Index of the first sample to be painted
to	Index of the last sample to be painted. If to < 0 the histogram will be painted to its last point.

See also:: setStyle(), style(), setPen()

void QwtPlotHistogram::drawOutline	(	QPainter *	painter,
		const QwtScaleMap &	xMap,
		const QwtScaleMap &	yMap,
		int	from,
		int	to
	)		const `[protected]`

Draw a histogram in Outline style()

Parameters:

painter	Painter
xMap	Maps x-values into pixel coordinates.
yMap	Maps y-values into pixel coordinates.
from	Index of the first sample to be painted
to	Index of the last sample to be painted. If to < 0 the histogram will be painted to its last point.

See also:: setStyle(), style()

Warning:: The outline style requires, that the intervals are in increasing order and not overlapping.

void QwtPlotHistogram::drawSeries	(	QPainter *	painter,
		const QwtScaleMap &	xMap,
		const QwtScaleMap &	yMap,
		const QRectF &	canvasRect,
		int	from,
		int	to
	)		const `[virtual]`

Draw a subset of the histogram samples

Parameters:

painter	Painter
xMap	Maps x-values into pixel coordinates.
yMap	Maps y-values into pixel coordinates.
canvasRect	Contents rect of the canvas
from	Index of the first sample to be painted
to	Index of the last sample to be painted. If to < 0 the series will be painted to its last sample.

See also:: drawOutline(), drawLines(), drawColumns

Implements QwtPlotAbstractSeriesItem.

void QwtPlotItem::hide ( ) [inherited]

Hide the item.

bool QwtPlotItem::isVisible ( ) const [inherited]

Returns:: true if visible

See also:: setVisible(), show(), hide()

void QwtPlotItem::itemChanged ( ) [virtual, inherited]

Update the legend and call QwtPlot::autoRefresh for the parent plot.

See also:: updateLegend()

QWidget * QwtPlotItem::legendItem ( ) const [virtual, inherited]

Allocate the widget that represents the item on the legend.

The default implementation returns a QwtLegendItem(), but an item could be represented by any type of widget, by overloading legendItem() and updateLegend().

Returns:: QwtLegendItem()

See also:: updateLegend() QwtLegend()

Implements QwtLegendItemManager.

Qt::Orientation QwtPlotAbstractSeriesItem::orientation ( ) const [inherited]

Returns:: Orientation of the plot item

See also:: setOrientation()

QRectF QwtPlotItem::paintRect	(	const QwtScaleMap &	xMap,
		const QwtScaleMap &	yMap
	)		const `[inherited]`

Calculate the bounding paint rect of 2 maps.

Parameters:

xMap	X map
yMap	X map

Returns:: Bounding paint rect of the scale maps, normalized

const QPen & QwtPlotHistogram::pen ( ) const

Returns:: Pen used in a style() depending way.

See also:: setPen(), brush()

QwtPlot * QwtPlotItem::plot ( ) const [inherited]

Return attached plot.

int QwtPlotHistogram::rtti ( ) const [virtual]

Returns:: QwtPlotItem::Rtti_PlotHistogram

Reimplemented from QwtPlotItem.

QRectF QwtPlotItem::scaleRect	(	const QwtScaleMap &	xMap,
		const QwtScaleMap &	yMap
	)		const `[inherited]`

Calculate the bounding scale rect of 2 maps.

Parameters:

xMap	X map
yMap	X map

Returns:: Bounding scale rect of the scale maps, normalized

void QwtPlotItem::setAxes	(	int	xAxis,
		int	yAxis
	)		`[inherited]`

Set X and Y axis

The item will painted according to the coordinates its Axes.

Parameters:

xAxis	X Axis
yAxis	Y Axis

See also:: setXAxis(), setYAxis(), xAxis(), yAxis()

void QwtPlotHistogram::setBaseline ( double value )

Set the value of the baseline.

Each column representing an QwtIntervalSample is defined by its interval and the interval between baseline and the value of the sample.

The default value of the baseline is 0.0.

Parameters:

value Value of the baseline

See also:: baseline()

void QwtPlotHistogram::setBrush ( const QBrush & brush )

Assign a brush, that is used in a style() depending way.

Parameters:

brush New brush

See also:: pen(), brush()

void QwtPlotItem::setItemAttribute	(	ItemAttribute	attribute,
		bool	on = `true`
	)		`[inherited]`

Toggle an item attribute

Parameters:

attribute	Attribute type
on	true/false

See also:: testItemAttribute(), ItemAttribute

void QwtPlotAbstractSeriesItem::setOrientation ( Qt::Orientation orientation ) [inherited]

Set the orientation of the item.

The orientation() might be used in specific way by a plot item. F.e. a QwtPlotCurve uses it to identify how to display the curve int QwtPlotCurve::Steps or QwtPlotCurve::Sticks style.

See also:: orientation()

void QwtPlotHistogram::setPen ( const QPen & pen )

Assign a pen, that is used in a style() depending way.

Parameters:

pen New pen

See also:: pen(), brush()

void QwtPlotItem::setRenderHint	(	RenderHint	hint,
		bool	on = `true`
	)		`[inherited]`

Toggle an render hint

Parameters:

hint	Render hint
on	true/false

See also:: testRenderHint(), RenderHint

void QwtPlotHistogram::setSamples ( const QVector< QwtIntervalSample > & samples )

Initialize data with an array of samples.

Parameters:

samples Vector of points

void QwtPlotHistogram::setStyle ( HistogramStyle style )

Set the histogram's drawing style

Parameters:

style Histogram style

See also:: HistogramStyle, style()

void QwtPlotHistogram::setSymbol ( const QwtColumnSymbol * symbol )

Assign a symbol.

In Column style an optional symbol can be assigned, that is responsible for displaying the rectangle that is defined by the interval and the distance between baseline() and value. When no symbol has been defined the area is displayed as plain rectangle using pen() and brush().

See also:: style(), symbol(), drawColumn(), pen(), brush()

Note:: In applications, where different intervals need to be displayed in a different way ( f.e different colors or even using differnt symbols) it is recommended to overload drawColumn().

void QwtPlotItem::setTitle ( const QString & title ) [inherited]

Set a new title

Parameters:

title Title

See also:: title()

void QwtPlotItem::setTitle ( const QwtText & title ) [inherited]

Set a new title

Parameters:

title Title

See also:: title()

void QwtPlotItem::setVisible ( bool on ) [virtual, inherited]

Show/Hide the item

Parameters:

on	Show if true, otherwise hide

See also:: isVisible(), show(), hide()

void QwtPlotItem::setXAxis ( int axis ) [inherited]

Set the X axis

The item will painted according to the coordinates its Axes.

Parameters:

axis X Axis

See also:: setAxes(), setYAxis(), xAxis()

void QwtPlotItem::setYAxis ( int axis ) [inherited]

Set the Y axis

The item will painted according to the coordinates its Axes.

Parameters:

axis Y Axis

See also:: setAxes(), setXAxis(), yAxis()

void QwtPlotItem::setZ ( double z ) [inherited]

Set the z value.

Plot items are painted in increasing z-order.

Parameters:

z Z-value

See also:: z(), QwtPlotDict::itemList()

void QwtPlotItem::show ( ) [inherited]

Show the item.

QwtPlotHistogram::HistogramStyle QwtPlotHistogram::style ( ) const

Return the current style

See also:: HistogramStyle, setStyle()

const QwtColumnSymbol * QwtPlotHistogram::symbol ( ) const

Returns:: Current symbol or NULL, when no symbol has been assigned

See also:: setSymbol()

bool QwtPlotItem::testItemAttribute ( ItemAttribute attribute ) const [inherited]

Test an item attribute

Parameters:

attribute Attribute type

Returns:: true/false

See also:: setItemAttribute(), ItemAttribute

bool QwtPlotItem::testRenderHint ( RenderHint hint ) const [inherited]

Test a render hint

Parameters:

hint	Render hint

Returns:: true/false

See also:: setRenderHint(), RenderHint

const QwtText & QwtPlotItem::title ( ) const [inherited]

Returns:: Title of the item

See also:: setTitle()

void QwtPlotItem::updateLegend ( QwtLegend * legend ) const [virtual, inherited]

Update the widget that represents the item on the legend.

updateLegend() is called from itemChanged() to adopt the widget representing the item on the legend to its new configuration.

The default implementation updates a QwtLegendItem(), but an item could be represented by any type of widget, by overloading legendItem() and updateLegend().

Parameters:

legend Legend

See also:: legendItem(), itemChanged(), QwtLegend()

Implements QwtLegendItemManager.

Reimplemented in QwtPlotCurve, and QwtPlotMarker.

virtual void QwtPlotSeriesItem< QwtIntervalSample >::updateScaleDiv	(	const QwtScaleDiv &	xScaleDiv,
		const QwtScaleDiv &	yScaleDiv
	)		`[virtual, inherited]`

Update the rect of interest according to the current scale ranges

Parameters:

xScaleDiv	Scale division of the x-axis
yScaleDiv	Scale division of the y-axis

See also:: QwtSeriesData<T>::setRectOfInterest()

Reimplemented from QwtPlotItem.

int QwtPlotItem::xAxis ( ) const [inherited]

Return xAxis.

int QwtPlotItem::yAxis ( ) const [inherited]

Return yAxis.

double QwtPlotItem::z ( ) const [inherited]

Plot items are painted in increasing z-order.

Returns:: setZ(), QwtPlotDict::itemList()

Member Data Documentation

QwtSeriesData<QwtIntervalSample >* QwtPlotSeriesItem< QwtIntervalSample >::d_series [protected, inherited]

Series.

Public Types

Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Member Typedef Documentation

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation