QwtPlotCurve(3) Qwt User's Guide QwtPlotCurve(3) NAME QwtPlotCurve - A plot item, that represents a series of points. SYNOPSIS #include Inherits QwtPlotSeriesItem, and QwtSeriesStore< QPointF >. Public Types enum CurveStyle { NoCurve = -1, Lines, Sticks, Steps, Dots, UserCurve = 100 } enum CurveAttribute { Inverted = 0x01, Fitted = 0x02 } enum LegendAttribute { LegendNoAttribute = 0x00, LegendShowLine = 0x01, LegendShowSymbol = 0x02, LegendShowBrush = 0x04 } enum PaintAttribute { ClipPolygons = 0x01, FilterPoints = 0x02, MinimizeMemory = 0x04, ImageBuffer = 0x08, FilterPointsAggressive = 0x10 } typedef QFlags< CurveAttribute > CurveAttributes typedef QFlags< LegendAttribute > LegendAttributes typedef QFlags< PaintAttribute > PaintAttributes Public Member Functions QwtPlotCurve (const QString &title=QString()) QwtPlotCurve (const QwtText &title) virtual ~QwtPlotCurve () Destructor. virtual int rtti () const override void setPaintAttribute (PaintAttribute, bool on=true) bool testPaintAttribute (PaintAttribute) const void setLegendAttribute (LegendAttribute, bool on=true) bool testLegendAttribute (LegendAttribute) const void setLegendAttributes (LegendAttributes) LegendAttributes legendAttributes () const void setRawSamples (const double *xData, const double *yData, int size) Initialize the data by pointing to memory blocks which are not managed by QwtPlotCurve. void setRawSamples (const float *xData, const float *yData, int size) Initialize the data by pointing to memory blocks which are not managed by QwtPlotCurve. void setRawSamples (const double *yData, int size) Initialize the data by pointing to a memory block which is not managed by QwtPlotCurve. void setRawSamples (const float *yData, int size) Initialize the data by pointing to memory blocks which are not managed by QwtPlotCurve. void setSamples (const double *xData, const double *yData, int size) void setSamples (const float *xData, const float *yData, int size) void setSamples (const double *yData, int size) void setSamples (const float *yData, int size) void setSamples (const QVector< double > &yData) void setSamples (const QVector< float > &yData) void setSamples (const QVector< double > &xData, const QVector< double > &yData) Initialize data with x- and y-arrays (explicitly shared) void setSamples (const QVector< float > &xData, const QVector< float > &yData) Initialize data with x- and y-arrays (explicitly shared) void setSamples (const QVector< QPointF > &) void setSamples (QwtSeriesData< QPointF > *) virtual int closestPoint (const QPointF &pos, double *dist=NULL) const double minXValue () const boundingRect().left() double maxXValue () const boundingRect().right() double minYValue () const boundingRect().top() double maxYValue () const boundingRect().bottom() void setCurveAttribute (CurveAttribute, bool on=true) bool testCurveAttribute (CurveAttribute) const void setPen (const QColor &, qreal width=0.0, Qt::PenStyle=Qt::SolidLine) void setPen (const QPen &) const QPen & pen () const void setBrush (const QBrush &) Assign a brush. const QBrush & brush () const void setBaseline (double) Set the value of the baseline. double baseline () const void setStyle (CurveStyle style) CurveStyle style () const void setSymbol (QwtSymbol *) Assign a symbol. const QwtSymbol * symbol () const void setCurveFitter (QwtCurveFitter *) QwtCurveFitter * curveFitter () const virtual void drawSeries (QPainter *, const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRectF &canvasRect, int from, int to) const override virtual QwtGraphic legendIcon (int index, const QSizeF &) const override Protected Member Functions void init () Initialize internal members. virtual void drawCurve (QPainter *, int style, const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRectF &canvasRect, int from, int to) const Draw the line part (without symbols) of a curve interval. virtual void drawSymbols (QPainter *, const QwtSymbol &, const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRectF &canvasRect, int from, int to) const virtual void drawLines (QPainter *, const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRectF &canvasRect, int from, int to) const Draw lines. virtual void drawSticks (QPainter *, const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRectF &canvasRect, int from, int to) const virtual void drawDots (QPainter *, const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRectF &canvasRect, int from, int to) const virtual void drawSteps (QPainter *, const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRectF &canvasRect, int from, int to) const virtual void fillCurve (QPainter *, const QwtScaleMap &, const QwtScaleMap &, const QRectF &canvasRect, QPolygonF &) const void closePolyline (QPainter *, const QwtScaleMap &, const QwtScaleMap &, QPolygonF &) const Complete a polygon to be a closed polygon including the area between the original polygon and the baseline. Detailed Description A plot item, that represents a series of points. A curve is the representation of a series of points in the x-y plane. It supports different display styles, interpolation ( f.e. spline ) and symbols. Usage a) Assign curve properties When a curve is created, it is configured to draw black solid lines with in QwtPlotCurve::Lines style and no symbols. You can change this by calling setPen(), setStyle() and setSymbol(). b) Connect/Assign data. QwtPlotCurve gets its points using a QwtSeriesData object offering a bridge to the real storage of the points ( like QAbstractItemModel ). There are several convenience classes derived from QwtSeriesData, that also store the points inside ( like QStandardItemModel ). QwtPlotCurve also offers a couple of variations of setSamples(), that build QwtSeriesData objects from arrays internally. c) Attach the curve to a plot See QwtPlotItem::attach() Example: see examples/bode See also QwtPointSeriesData, QwtSymbol, QwtScaleMap Definition at line 56 of file qwt_plot_curve.h. Member Typedef Documentation typedef QFlags QwtPlotCurve::CurveAttributes An ORed combination of CurveAttribute values. Definition at line 133 of file qwt_plot_curve.h. typedef QFlags QwtPlotCurve::LegendAttributes An ORed combination of LegendAttribute values. Definition at line 168 of file qwt_plot_curve.h. typedef QFlags QwtPlotCurve::PaintAttributes An ORed combination of PaintAttribute values. Definition at line 234 of file qwt_plot_curve.h. Member Enumeration Documentation enum QwtPlotCurve::CurveAttribute Attribute for drawing the curve See also setCurveAttribute(), testCurveAttribute(), curveFitter() Enumerator Inverted For QwtPlotCurve::Steps only. Draws a step function from the right to the left. Fitted Only in combination with QwtPlotCurve::Lines A QwtCurveFitter tries to interpolate/smooth the curve, before it is painted. Note Curve fitting requires temporary memory for calculating coefficients and additional points. If painting in QwtPlotCurve::Fitted mode is slow it might be better to fit the points, before they are passed to QwtPlotCurve. Definition at line 112 of file qwt_plot_curve.h. enum QwtPlotCurve::CurveStyle Curve styles. See also setStyle(), style() Enumerator NoCurve Don't draw a curve. Note: This doesn't affect the symbols. Lines Connect the points with straight lines. The lines might be interpolated depending on the 'Fitted' attribute. Curve fitting can be configured using setCurveFitter(). Sticks Draw vertical or horizontal sticks ( depending on the orientation() ) from a baseline which is defined by setBaseline(). Steps Connect the points with a step function. The step function is drawn from the left to the right or vice versa, depending on the QwtPlotCurve::Inverted attribute. Dots Draw dots at the locations of the data points. Note: This is different from a dotted line (see setPen()), and faster as a curve in QwtPlotCurve::NoStyle style and a symbol painting a point. UserCurve Styles >= QwtPlotCurve::UserCurve are reserved for derived classes of QwtPlotCurve that overload drawCurve() with additional application specific curve types. Definition at line 65 of file qwt_plot_curve.h. enum QwtPlotCurve::LegendAttribute Attributes how to represent the curve on the legend See also setLegendAttribute(), testLegendAttribute(), QwtPlotItem::legendData(), legendIcon() Enumerator LegendNoAttribute QwtPlotCurve tries to find a color representing the curve and paints a rectangle with it. LegendShowLine If the style() is not QwtPlotCurve::NoCurve a line is painted with the curve pen(). LegendShowSymbol If the curve has a valid symbol it is painted. LegendShowBrush If the curve has a brush a rectangle filled with the curve brush() is painted. Definition at line 142 of file qwt_plot_curve.h. enum QwtPlotCurve::PaintAttribute Attributes to modify the drawing algorithm. The default setting enables ClipPolygons | FilterPoints See also setPaintAttribute(), testPaintAttribute() Enumerator ClipPolygons Clip polygons before painting them. In situations, where points are far outside the visible area (f.e when zooming deep) this might be a substantial improvement for the painting performance FilterPoints Tries to reduce the data that has to be painted, by sorting out duplicates, or paintings outside the visible area. Might have a notable impact on curves with many close points. Only a couple of very basic filtering algorithms are implemented. MinimizeMemory Minimize memory usage that is temporarily needed for the translated points, before they get painted. This might slow down the performance of painting ImageBuffer Render the points to a temporary image and paint the image. This is a very special optimization for Dots style, when having a huge amount of points. With a reasonable number of points QPainter::drawPoints() will be faster. FilterPointsAggressive More aggressive point filtering trying to filter out intermediate points, accepting minor visual differences. Has only an effect, when drawing the curve to a paint device in integer coordinates ( f.e. all widgets on screen ) using the fact, that consecutive points are often mapped to the same x or y coordinate. Each chunk of samples mapped to the same coordinate can be reduced to 4 points ( first, min, max last ). In the worst case the polygon to be rendered will be 4 times the width of the plot canvas. The algorithm is very fast and effective for huge datasets, and can be used inside a replot cycle. Note Implemented for QwtPlotCurve::Lines only As this algo replaces many small lines by a long one a nasty bug of the raster paint engine ( Qt 4.8, Qt 5.1 - 5.3 ) becomes more dominant. For these versions the bug can be worked around by enabling the QwtPainter::polylineSplitting() mode. Definition at line 176 of file qwt_plot_curve.h. Constructor & Destructor Documentation QwtPlotCurve::QwtPlotCurve (const QString & title = QString()) [explicit] Constructor Parameters title Title of the curve Definition at line 120 of file qwt_plot_curve.cpp. QwtPlotCurve::QwtPlotCurve (const QwtText & title) [explicit] Constructor Parameters title Title of the curve Definition at line 110 of file qwt_plot_curve.cpp. Member Function Documentation double QwtPlotCurve::baseline () const Returns Value of the baseline See also setBaseline() Definition at line 1035 of file qwt_plot_curve.cpp. const QBrush & QwtPlotCurve::brush () const Returns Brush used to fill the area between lines and the baseline See also setBrush(), setBaseline(), baseline() Definition at line 363 of file qwt_plot_curve.cpp. void QwtPlotCurve::closePolyline (QPainter * painter, const QwtScaleMap & xMap, const QwtScaleMap & yMap, QPolygonF & polygon) const [protected] Complete a polygon to be a closed polygon including the area between the original polygon and the baseline. Parameters painter Painter xMap X map yMap Y map polygon Polygon to be completed Definition at line 929 of file qwt_plot_curve.cpp. int QwtPlotCurve::closestPoint (const QPointF & pos, double * dist = NULL) const [virtual] Find the closest curve point for a specific position Parameters pos Position, where to look for the closest curve point dist If dist != NULL, closestPoint() returns the distance between the position and the closest curve point Returns Index of the closest curve point, or -1 if none can be found ( f.e when the curve has no points ) Note closestPoint() implements a dumb algorithm, that iterates over all points Definition at line 1051 of file qwt_plot_curve.cpp. QwtCurveFitter * QwtPlotCurve::curveFitter () const Get the curve fitter. If curve fitting is disabled NULL is returned. Returns Curve fitter See also setCurveFitter(), Fitted Definition at line 872 of file qwt_plot_curve.cpp. void QwtPlotCurve::drawCurve (QPainter * painter, int style, const QwtScaleMap & xMap, const QwtScaleMap & yMap, const QRectF & canvasRect, int from, int to) const [protected], [virtual] Draw the line part (without symbols) of a curve interval. Parameters painter Painter style curve style, see QwtPlotCurve::CurveStyle xMap x map yMap y map canvasRect Contents rectangle of the canvas from index of the first point to be painted to index of the last point to be painted See also draw(), drawDots(), drawLines(), drawSteps(), drawSticks() Definition at line 429 of file qwt_plot_curve.cpp. void QwtPlotCurve::drawDots (QPainter * painter, const QwtScaleMap & xMap, const QwtScaleMap & yMap, const QRectF & canvasRect, int from, int to) const [protected], [virtual] Draw dots Parameters painter Painter xMap x map yMap y map canvasRect Contents rectangle of the canvas from index of the first point to be painted to index of the last point to be painted See also draw(), drawCurve(), drawSticks(), drawLines(), drawSteps() Definition at line 640 of file qwt_plot_curve.cpp. void QwtPlotCurve::drawLines (QPainter * painter, const QwtScaleMap & xMap, const QwtScaleMap & yMap, const QRectF & canvasRect, int from, int to) const [protected], [virtual] Draw lines. If the CurveAttribute Fitted is enabled a QwtCurveFitter tries to interpolate/smooth the curve, before it is painted. Parameters painter Painter xMap x map yMap y map canvasRect Contents rectangle of the canvas from index of the first point to be painted to index of the last point to be painted See also setCurveAttribute(), setCurveFitter(), draw(), drawLines(), drawDots(), drawSteps(), drawSticks() Definition at line 476 of file qwt_plot_curve.cpp. void QwtPlotCurve::drawSeries (QPainter * painter, const QwtScaleMap & xMap, const QwtScaleMap & yMap, const QRectF & canvasRect, int from, int to) const [override], [virtual] Draw an interval of the curve Parameters painter Painter xMap Maps x-values into pixel coordinates. yMap Maps y-values into pixel coordinates. canvasRect Contents rectangle of the canvas from Index of the first point to be painted to Index of the last point to be painted. If to < 0 the curve will be painted to its last point. See also drawCurve(), drawSymbols(), Implements QwtPlotSeriesItem. Definition at line 381 of file qwt_plot_curve.cpp. void QwtPlotCurve::drawSteps (QPainter * painter, const QwtScaleMap & xMap, const QwtScaleMap & yMap, const QRectF & canvasRect, int from, int to) const [protected], [virtual] Draw step function The direction of the steps depends on Inverted attribute. Parameters painter Painter xMap x map yMap y map canvasRect Contents rectangle of the canvas from index of the first point to be painted to index of the last point to be painted See also CurveAttribute, setCurveAttribute(), draw(), drawCurve(), drawDots(), drawLines(), drawSticks() Definition at line 741 of file qwt_plot_curve.cpp. void QwtPlotCurve::drawSticks (QPainter * painter, const QwtScaleMap & xMap, const QwtScaleMap & yMap, const QRectF & canvasRect, int from, int to) const [protected], [virtual] Draw sticks Parameters painter Painter xMap x map yMap y map canvasRect Contents rectangle of the canvas from index of the first point to be painted to index of the last point to be painted See also draw(), drawCurve(), drawDots(), drawLines(), drawSteps() Definition at line 585 of file qwt_plot_curve.cpp. void QwtPlotCurve::drawSymbols (QPainter * painter, const QwtSymbol & symbol, const QwtScaleMap & xMap, const QwtScaleMap & yMap, const QRectF & canvasRect, int from, int to) const [protected], [virtual] Draw symbols Parameters painter Painter symbol Curve symbol xMap x map yMap y map canvasRect Contents rectangle of the canvas from Index of the first point to be painted to Index of the last point to be painted See also setSymbol(), drawSeries(), drawCurve() Definition at line 979 of file qwt_plot_curve.cpp. void QwtPlotCurve::fillCurve (QPainter * painter, const QwtScaleMap & xMap, const QwtScaleMap & yMap, const QRectF & canvasRect, QPolygonF & polygon) const [protected], [virtual] Fill the area between the curve and the baseline with the curve brush Parameters painter Painter xMap x map yMap y map canvasRect Contents rectangle of the canvas polygon Polygon - will be modified ! See also setBrush(), setBaseline(), setStyle() Definition at line 889 of file qwt_plot_curve.cpp. QwtPlotCurve::LegendAttributes QwtPlotCurve::legendAttributes () const Returns Attributes how to draw the legend icon See also setLegendAttributes(), testLegendAttribute() Definition at line 225 of file qwt_plot_curve.cpp. QwtGraphic QwtPlotCurve::legendIcon (int index, const QSizeF & size) const [override], [virtual] Returns Icon representing the curve on the legend Parameters index Index of the legend entry ( ignored as there is only one ) size Icon size See also QwtPlotItem::setLegendIconSize(), QwtPlotItem::legendData() Reimplemented from QwtPlotItem. Definition at line 1095 of file qwt_plot_curve.cpp. const QPen & QwtPlotCurve::pen () const Returns Pen used to draw the lines See also setPen(), brush() Definition at line 328 of file qwt_plot_curve.cpp. int QwtPlotCurve::rtti () const [override], [virtual] Returns QwtPlotItem::Rtti_PlotCurve Reimplemented from QwtPlotItem. Definition at line 145 of file qwt_plot_curve.cpp. void QwtPlotCurve::setBaseline (double value) Set the value of the baseline. The baseline is needed for filling the curve with a brush or the Sticks drawing style. The interpretation of the baseline depends on the orientation(). With Qt::Vertical, the baseline is interpreted as a horizontal line at y = baseline(), with Qt::Horizontal, it is interpreted as a vertical line at x = baseline(). The default value is 0.0. Parameters value Value of the baseline See also baseline(), setBrush(), setStyle(), QwtPlotAbstractSeriesItem::orientation() Definition at line 1022 of file qwt_plot_curve.cpp. void QwtPlotCurve::setBrush (const QBrush & brush) Assign a brush. In case of brush.style() != QBrush::NoBrush and style() != QwtPlotCurve::Sticks the area between the curve and the baseline will be filled. In case !brush.color().isValid() the area will be filled by pen.color(). The fill algorithm simply connects the first and the last curve point to the baseline. So the curve data has to be sorted (ascending or descending). Parameters brush New brush See also brush(), setBaseline(), baseline() Definition at line 348 of file qwt_plot_curve.cpp. void QwtPlotCurve::setCurveAttribute (CurveAttribute attribute, bool on = true) Specify an attribute for drawing the curve Parameters attribute Curve attribute on On/Off /sa testCurveAttribute(), setCurveFitter() Definition at line 819 of file qwt_plot_curve.cpp. void QwtPlotCurve::setCurveFitter (QwtCurveFitter * curveFitter) Assign a curve fitter The curve fitter 'smooths' the curve points, when the Fitted CurveAttribute is set. setCurveFitter(NULL) also disables curve fitting. The curve fitter operates on the translated points ( = widget coordinates) to be functional for logarithmic scales. Obviously this is less performant for fitting algorithms, that reduce the number of points. For situations, where curve fitting is used to improve the performance of painting huge series of points it might be better to execute the fitter on the curve points once and to cache the result in the QwtSeriesData object. Parameters curveFitter() Curve fitter See also Fitted Definition at line 858 of file qwt_plot_curve.cpp. void QwtPlotCurve::setLegendAttribute (LegendAttribute attribute, bool on = true) Specify an attribute how to draw the legend icon Parameters attribute Attribute on On/Off /sa testLegendAttribute(). legendIcon() Definition at line 181 of file qwt_plot_curve.cpp. void QwtPlotCurve::setLegendAttributes (LegendAttributes attributes) Specify the attributes how to draw the legend icon Parameters attributes Attributes /sa setLegendAttribute(). legendIcon() Definition at line 210 of file qwt_plot_curve.cpp. void QwtPlotCurve::setPaintAttribute (PaintAttribute attribute, bool on = true) Specify an attribute how to draw the curve Parameters attribute Paint attribute on On/Off See also testPaintAttribute() Definition at line 157 of file qwt_plot_curve.cpp. void QwtPlotCurve::setPen (const QColor & color, qreal width = 0.0, Qt::PenStyle style = Qt::SolidLine) Build and assign a pen In Qt5 the default pen width is 1.0 ( 0.0 in Qt4 ) what makes it non cosmetic ( see QPen::isCosmetic() ). This method has been introduced to hide this incompatibility. Parameters color Pen color width Pen width style Pen style See also pen(), brush() Definition at line 302 of file qwt_plot_curve.cpp. void QwtPlotCurve::setPen (const QPen & pen) Assign a pen Parameters pen New pen See also pen(), brush() Definition at line 313 of file qwt_plot_curve.cpp. void QwtPlotCurve::setRawSamples (const double * xData, const double * yData, int size) Initialize the data by pointing to memory blocks which are not managed by QwtPlotCurve. setRawSamples is provided for efficiency. It is important to keep the pointers during the lifetime of the underlying QwtCPointerData class. Parameters xData pointer to x data yData pointer to y data size size of x and y See also QwtCPointerData Definition at line 1203 of file qwt_plot_curve.cpp. void QwtPlotCurve::setRawSamples (const double * yData, int size) Initialize the data by pointing to a memory block which is not managed by QwtPlotCurve. The memory contains the y coordinates, while the index is interpreted as x coordinate. setRawSamples() is provided for efficiency. It is important to keep the pointers during the lifetime of the underlying QwtCPointerValueData class. Parameters yData pointer to y data size size of x and y See also QwtCPointerData Definition at line 1245 of file qwt_plot_curve.cpp. void QwtPlotCurve::setRawSamples (const float * xData, const float * yData, int size) Initialize the data by pointing to memory blocks which are not managed by QwtPlotCurve. setRawSamples is provided for efficiency. It is important to keep the pointers during the lifetime of the underlying QwtCPointerData class. Parameters xData pointer to x data yData pointer to y data size size of x and y See also QwtCPointerData Definition at line 1223 of file qwt_plot_curve.cpp. void QwtPlotCurve::setRawSamples (const float * yData, int size) Initialize the data by pointing to memory blocks which are not managed by QwtPlotCurve. The memory contains the y coordinates, while the index is interpreted as x coordinate. setRawSamples() is provided for efficiency. It is important to keep the pointers during the lifetime of the underlying QwtCPointerValueData class. Parameters yData pointer to y data size size of x and y See also QwtCPointerData Definition at line 1266 of file qwt_plot_curve.cpp. void QwtPlotCurve::setSamples (const double * xData, const double * yData, int size) Set data by copying x- and y-values from specified memory blocks. Contrary to setRawSamples(), this function makes a 'deep copy' of the data. Parameters xData pointer to x values yData pointer to y values size size of xData and yData See also QwtPointArrayData Definition at line 1282 of file qwt_plot_curve.cpp. void QwtPlotCurve::setSamples (const double * yData, int size) Set data by copying y-values from a specified memory block. The memory contains the y coordinates, while the index is interpreted as x coordinate. Parameters yData y data size size of yData See also QwtValuePointData Definition at line 1344 of file qwt_plot_curve.cpp. void QwtPlotCurve::setSamples (const float * xData, const float * yData, int size) Set data by copying x- and y-values from specified memory blocks. Contrary to setRawSamples(), this function makes a 'deep copy' of the data. Parameters xData pointer to x values yData pointer to y values size size of xData and yData See also QwtPointArrayData Definition at line 1299 of file qwt_plot_curve.cpp. void QwtPlotCurve::setSamples (const float * yData, int size) Set data by copying y-values from a specified memory block. The vector contains the y coordinates, while the index is interpreted as x coordinate. Parameters yData y data size size of yData See also QwtValuePointData Definition at line 1360 of file qwt_plot_curve.cpp. void QwtPlotCurve::setSamples (const QVector< double > & xData, const QVector< double > & yData) Initialize data with x- and y-arrays (explicitly shared) Parameters xData x data yData y data See also QwtPointArrayData Definition at line 1313 of file qwt_plot_curve.cpp. void QwtPlotCurve::setSamples (const QVector< double > & yData) Initialize data with an array of y values (explicitly shared) The vector contains the y coordinates, while the index is the x coordinate. Parameters yData y data See also QwtValuePointData Definition at line 1375 of file qwt_plot_curve.cpp. void QwtPlotCurve::setSamples (const QVector< float > & xData, const QVector< float > & yData) Initialize data with x- and y-arrays (explicitly shared) Parameters xData x data yData y data See also QwtPointArrayData Definition at line 1327 of file qwt_plot_curve.cpp. void QwtPlotCurve::setSamples (const QVector< float > & yData) Initialize data with an array of y values (explicitly shared) The vector contains the y coordinates, while the index is the x coordinate. Parameters yData y data See also QwtValuePointData Definition at line 1390 of file qwt_plot_curve.cpp. void QwtPlotCurve::setSamples (const QVector< QPointF > & samples) Initialize data with an array of points. Parameters samples Vector of points Note QVector is implicitly shared QPolygonF is derived from QVector Definition at line 1184 of file qwt_plot_curve.cpp. void QwtPlotCurve::setSamples (QwtSeriesData< QPointF > * data) Assign a series of points setSamples() is just a wrapper for setData() without any additional value - beside that it is easier to find for the developer. Parameters data Data Warning The item takes ownership of the data object, deleting it when its not used anymore. Definition at line 1172 of file qwt_plot_curve.cpp. void QwtPlotCurve::setStyle (CurveStyle style) Set the curve's drawing style Parameters style Curve style See also style() Definition at line 236 of file qwt_plot_curve.cpp. void QwtPlotCurve::setSymbol (QwtSymbol * symbol) Assign a symbol. The curve will take the ownership of the symbol, hence the previously set symbol will be delete by setting a new one. If symbol is NULL no symbol will be drawn. Parameters symbol Symbol See also symbol() Definition at line 266 of file qwt_plot_curve.cpp. QwtPlotCurve::CurveStyle QwtPlotCurve::style () const Returns Style of the curve See also setStyle() Definition at line 251 of file qwt_plot_curve.cpp. const QwtSymbol * QwtPlotCurve::symbol () const Returns Current symbol or NULL, when no symbol has been assigned See also setSymbol() Definition at line 284 of file qwt_plot_curve.cpp. bool QwtPlotCurve::testCurveAttribute (CurveAttribute attribute) const Returns true, if attribute is enabled See also setCurveAttribute() Definition at line 836 of file qwt_plot_curve.cpp. bool QwtPlotCurve::testLegendAttribute (LegendAttribute attribute) const Returns True, when attribute is enabled See also setLegendAttribute() Definition at line 199 of file qwt_plot_curve.cpp. bool QwtPlotCurve::testPaintAttribute (PaintAttribute attribute) const Returns True, when attribute is enabled See also setPaintAttribute() Definition at line 169 of file qwt_plot_curve.cpp. Author Generated automatically by Doxygen for Qwt User's Guide from the source code. Version 6.2.0 Sun Jul 18 2021 QwtPlotCurve(3)