.TH "QwtPlotBarChart" 3 "Wed Jan 2 2019" "Version 6.1.4" "Qwt User's Guide" \" -*- nroff -*-
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.SH NAME
QwtPlotBarChart \- \fBQwtPlotBarChart\fP displays a series of a values as bars\&.  

.SH SYNOPSIS
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.PP
.PP
\fC#include <qwt_plot_barchart\&.h>\fP
.PP
Inherits \fBQwtPlotAbstractBarChart\fP, and \fBQwtSeriesStore< QPointF >\fP\&.
.SS "Public Types"

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.RI "enum \fBLegendMode\fP { \fBLegendChartTitle\fP, \fBLegendBarTitles\fP }"
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.RI "Legend modes\&. "
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.SS "Public Member Functions"

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.RI "\fBQwtPlotBarChart\fP (const QString &\fBtitle\fP=QString())"
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.RI "\fBQwtPlotBarChart\fP (const \fBQwtText\fP &\fBtitle\fP)"
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.RI "virtual \fB~QwtPlotBarChart\fP ()"
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.RI "Destructor\&. "
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.RI "virtual int \fBrtti\fP () const"
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.RI "void \fBsetSamples\fP (const QVector< QPointF > &)"
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.RI "void \fBsetSamples\fP (const QVector< double > &)"
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.RI "void \fBsetSamples\fP (\fBQwtSeriesData\fP< QPointF > *)"
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.RI "void \fBsetSymbol\fP (\fBQwtColumnSymbol\fP *)"
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.RI "Assign a symbol\&. "
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.RI "const \fBQwtColumnSymbol\fP * \fBsymbol\fP () const"
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.RI "void \fBsetLegendMode\fP (\fBLegendMode\fP)"
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.RI "\fBLegendMode\fP \fBlegendMode\fP () const"
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.RI "virtual void \fBdrawSeries\fP (QPainter *painter, const \fBQwtScaleMap\fP &xMap, const \fBQwtScaleMap\fP &yMap, const QRectF &canvasRect, int from, int to) const"
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.RI "virtual QRectF \fBboundingRect\fP () const"
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.RI "virtual \fBQwtColumnSymbol\fP * \fBspecialSymbol\fP (int sampleIndex, const QPointF &) const"
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.RI "virtual \fBQwtText\fP \fBbarTitle\fP (int sampleIndex) const"
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.RI "Return the title of a bar\&. "
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.SS "Protected Member Functions"

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.RI "virtual void \fBdrawSample\fP (QPainter *painter, const \fBQwtScaleMap\fP &xMap, const \fBQwtScaleMap\fP &yMap, const QRectF &canvasRect, const \fBQwtInterval\fP &boundingInterval, int index, const QPointF &\fBsample\fP) const"
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.RI "virtual void \fBdrawBar\fP (QPainter *, int sampleIndex, const QPointF &\fBsample\fP, const \fBQwtColumnRect\fP &) const"
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.RI "QList< \fBQwtLegendData\fP > \fBlegendData\fP () const"
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.RI "Return all information, that is needed to represent the item on the legend\&. "
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.RI "\fBQwtGraphic\fP \fBlegendIcon\fP (int index, const QSizeF &) const"
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.SH "Detailed Description"
.PP 
\fBQwtPlotBarChart\fP displays a series of a values as bars\&. 

Each bar might be customized individually by implementing a \fBspecialSymbol()\fP\&. Otherwise it is rendered using a default symbol\&.
.PP
Depending on its \fBorientation()\fP the bars are displayed horizontally or vertically\&. The bars cover the interval between the \fBbaseline()\fP and the value\&.
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By activating the LegendBarTitles mode each sample will have its own entry on the legend\&.
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The most common use case of a bar chart is to display a list of y coordinates, where the x coordinate is simply the index in the list\&. But for other situations ( f\&.e\&. when values are related to dates ) it is also possible to set x coordinates explicitly\&.
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\fBSee also:\fP
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\fBQwtPlotMultiBarChart\fP, \fBQwtPlotHistogram\fP, \fBQwtPlotCurve::Sticks\fP, \fBQwtPlotSeriesItem::orientation()\fP, \fBQwtPlotAbstractBarChart::baseline()\fP 
.RE
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.SH "Member Enumeration Documentation"
.PP 
.SS "enum \fBQwtPlotBarChart::LegendMode\fP"

.PP
Legend modes\&. The default setting is \fBQwtPlotBarChart::LegendChartTitle\fP\&. 
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\fBSee also:\fP
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\fBsetLegendMode()\fP, \fBlegendMode()\fP 
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.PP
\fBEnumerator\fP
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.TP
\fB\fILegendChartTitle \fP\fP
One entry on the legend showing the default symbol and the \fBtitle()\fP of the chart
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\fBSee also:\fP
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\fBQwtPlotItem::title()\fP 
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.TP
\fB\fILegendBarTitles \fP\fP
One entry for each value showing the individual symbol of the corresponding bar and the bar title\&.
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\fBSee also:\fP
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\fBspecialSymbol()\fP, \fBbarTitle()\fP 
.RE
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.SH "Constructor & Destructor Documentation"
.PP 
.SS "QwtPlotBarChart::QwtPlotBarChart (const QString & title = \fCQString()\fP)\fC [explicit]\fP"
Constructor 
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\fBParameters:\fP
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\fItitle\fP Title of the curve 
.RE
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.SS "QwtPlotBarChart::QwtPlotBarChart (const \fBQwtText\fP & title)\fC [explicit]\fP"
Constructor 
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\fBParameters:\fP
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\fItitle\fP Title of the curve 
.RE
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.SH "Member Function Documentation"
.PP 
.SS "\fBQwtText\fP QwtPlotBarChart::barTitle (int sampleIndex) const\fC [virtual]\fP"

.PP
Return the title of a bar\&. In LegendBarTitles mode the title is displayed on the legend entry corresponding to a bar\&.
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The default implementation is a dummy, that is intended to be overloaded\&.
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\fBParameters:\fP
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\fIsampleIndex\fP Index of the bar 
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\fBReturns:\fP
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An empty text 
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\fBSee also:\fP
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\fBLegendBarTitles\fP 
.RE
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.SS "QRectF QwtPlotBarChart::boundingRect () const\fC [virtual]\fP"

.PP
\fBReturns:\fP
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Bounding rectangle of all samples\&. For an empty series the rectangle is invalid\&. 
.RE
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.PP
Reimplemented from \fBQwtPlotSeriesItem\fP\&.
.SS "void QwtPlotBarChart::drawBar (QPainter * painter, int sampleIndex, const QPointF & sample, const \fBQwtColumnRect\fP & rect) const\fC [protected]\fP, \fC [virtual]\fP"
Draw a bar
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\fBParameters:\fP
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\fIpainter\fP Painter 
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\fIsampleIndex\fP Index of the sample represented by the bar 
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\fIsample\fP Value of the sample 
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\fIrect\fP Bounding rectangle of the bar 
.RE
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.SS "void QwtPlotBarChart::drawSample (QPainter * painter, const \fBQwtScaleMap\fP & xMap, const \fBQwtScaleMap\fP & yMap, const QRectF & canvasRect, const \fBQwtInterval\fP & boundingInterval, int index, const QPointF & sample) const\fC [protected]\fP, \fC [virtual]\fP"
Draw a sample
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\fBParameters:\fP
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\fIpainter\fP Painter 
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\fIxMap\fP x map 
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\fIyMap\fP y map 
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\fIcanvasRect\fP Contents rect of the canvas 
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\fIboundingInterval\fP Bounding interval of sample values 
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\fIindex\fP Index of the sample 
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\fIsample\fP Value of the sample
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\fBSee also:\fP
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\fBdrawSeries()\fP 
.RE
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.SS "void QwtPlotBarChart::drawSeries (QPainter * painter, const \fBQwtScaleMap\fP & xMap, const \fBQwtScaleMap\fP & yMap, const QRectF & canvasRect, int from, int to) const\fC [virtual]\fP"
Draw an interval of the bar chart
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\fBParameters:\fP
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\fIpainter\fP Painter 
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\fIxMap\fP Maps x-values into pixel coordinates\&. 
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\fIyMap\fP Maps y-values into pixel coordinates\&. 
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\fIcanvasRect\fP Contents rect of the canvas 
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\fIfrom\fP Index of the first point to be painted 
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\fIto\fP Index of the last point to be painted\&. If to < 0 the curve will be painted to its last point\&.
.RE
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\fBSee also:\fP
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drawSymbols() 
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.PP
Implements \fBQwtPlotSeriesItem\fP\&.
.SS "QList< \fBQwtLegendData\fP > QwtPlotBarChart::legendData () const\fC [protected]\fP, \fC [virtual]\fP"

.PP
Return all information, that is needed to represent the item on the legend\&. In case of LegendBarTitles an entry for each bar is returned, otherwise the chart is represented like any other plot item from its \fBtitle()\fP and the \fBlegendIcon()\fP\&.
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\fBReturns:\fP
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Information, that is needed to represent the item on the legend 
.RE
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\fBSee also:\fP
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\fBtitle()\fP, \fBsetLegendMode()\fP, \fBbarTitle()\fP, \fBQwtLegend\fP, \fBQwtPlotLegendItem\fP 
.RE
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.PP
Reimplemented from \fBQwtPlotItem\fP\&.
.SS "\fBQwtGraphic\fP QwtPlotBarChart::legendIcon (int index, const QSizeF & size) const\fC [protected]\fP, \fC [virtual]\fP"

.PP
\fBReturns:\fP
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Icon representing a bar or the chart on the legend
.RE
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When the \fBlegendMode()\fP is LegendBarTitles the icon shows the bar corresponding to index - otherwise the bar displays the default symbol\&.
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\fBParameters:\fP
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\fIindex\fP Index of the legend entry 
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\fIsize\fP Icon size
.RE
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\fBSee also:\fP
.RS 4
\fBsetLegendMode()\fP, \fBdrawBar()\fP, \fBQwtPlotItem::setLegendIconSize()\fP, \fBQwtPlotItem::legendData()\fP 
.RE
.PP

.PP
Reimplemented from \fBQwtPlotItem\fP\&.
.SS "\fBQwtPlotBarChart::LegendMode\fP QwtPlotBarChart::legendMode () const"

.PP
\fBReturns:\fP
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Legend mode 
.RE
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\fBSee also:\fP
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\fBsetLegendMode()\fP 
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.SS "int QwtPlotBarChart::rtti () const\fC [virtual]\fP"

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\fBReturns:\fP
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\fBQwtPlotItem::Rtti_PlotBarChart\fP 
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.PP
Reimplemented from \fBQwtPlotItem\fP\&.
.SS "void QwtPlotBarChart::setLegendMode (\fBLegendMode\fP mode)"
Set the mode that decides what to display on the legend
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In case of LegendBarTitles \fBbarTitle()\fP needs to be overloaded to return individual titles for each bar\&.
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\fBParameters:\fP
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\fImode\fP New mode 
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\fBSee also:\fP
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\fBlegendMode()\fP, \fBlegendData()\fP, \fBbarTitle()\fP, \fBQwtPlotItem::ItemAttribute\fP 
.RE
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.SS "void QwtPlotBarChart::setSamples (const QVector< QPointF > & samples)"
Initialize data with an array of points
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\fBParameters:\fP
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\fIsamples\fP Vector of points 
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\fBNote:\fP
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QVector is implicitly shared 
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QPolygonF is derived from QVector<QPointF> 
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.SS "void QwtPlotBarChart::setSamples (const QVector< double > & samples)"
Initialize data with an array of doubles
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The indices in the array are taken as x coordinate, while the doubles are interpreted as y values\&.
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\fBParameters:\fP
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\fIsamples\fP Vector of y coordinates 
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\fBNote:\fP
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QVector is implicitly shared 
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.SS "void QwtPlotBarChart::setSamples (\fBQwtSeriesData\fP< QPointF > * data)"
Assign a series of samples
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\fBsetSamples()\fP is just a wrapper for \fBsetData()\fP without any additional value - beside that it is easier to find for the developer\&.
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\fBParameters:\fP
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\fIdata\fP Data 
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\fBWarning:\fP
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The item takes ownership of the data object, deleting it when its not used anymore\&. 
.RE
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.SS "void QwtPlotBarChart::setSymbol (\fBQwtColumnSymbol\fP * symbol)"

.PP
Assign a symbol\&. The bar chart will take the ownership of the symbol, hence the previously set symbol will be delete by setting a new one\&. If \fCsymbol\fP is \fCNULL\fP no symbol will be drawn\&.
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\fBParameters:\fP
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\fIsymbol\fP Symbol 
.RE
.PP
\fBSee also:\fP
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\fBsymbol()\fP 
.RE
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.SS "\fBQwtColumnSymbol\fP * QwtPlotBarChart::specialSymbol (int sampleIndex, const QPointF & sample) const\fC [virtual]\fP"
Needs to be overloaded to return a non default symbol for a specific sample
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\fBParameters:\fP
.RS 4
\fIsampleIndex\fP Index of the sample represented by the bar 
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\fIsample\fP Value of the sample
.RE
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\fBReturns:\fP
.RS 4
NULL, indicating to use the default symbol 
.RE
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.SS "const \fBQwtColumnSymbol\fP * QwtPlotBarChart::symbol () const"

.PP
\fBReturns:\fP
.RS 4
Current symbol or NULL, when no symbol has been assigned 
.RE
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\fBSee also:\fP
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\fBsetSymbol()\fP 
.RE
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.SH "Author"
.PP 
Generated automatically by Doxygen for Qwt User's Guide from the source code\&.