conflicting packages
QwtPlotCurve(3) | Qwt User's Guide | QwtPlotCurve(3) |
NAME¶
QwtPlotCurve - A plot item, that represents a series of points.SYNOPSIS¶
#include <qwt_plot_curve.h> Inherits QwtPlotItem.Public Types¶
enum CurveAttribute { Inverted = 1, Fitted = 2 }
Public Member Functions¶
void attach (QwtPlot *plot)
Protected Member Functions¶
void closePolyline (const QwtScaleMap &, const QwtScaleMap &, QwtPolygon &) const
Detailed Description¶
A plot item, that represents a series of points.- a) Assign curve properties
- When a curve is created, it is configured to draw black solid lines with in 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 QwtData object offering a bridge to the real storage of the points ( like QAbstractItemModel ). There are several convenience classes derived from QwtData, that also store the points inside ( like QStandardItemModel ). QwtPlotCurve also offers a couple of variations of setData(), that build QwtData objects from arrays internally.
- c) Attach the curve to a plot
- See QwtPlotItem::attach()
see examples/bode
See also:
QwtPlot, QwtData,
QwtSymbol, QwtScaleMap
Member Enumeration Documentation¶
enum QwtPlotCurve::CurveAttribute Attribute for drawing the curve¶
- •
- Fitted ( in combination with the Lines
QwtPlotCurve::CurveStyle only )
A QwtCurveFitter tries to interpolate/smooth the curve, before it is painted. Note that curve fitting requires temorary memory for calculating coefficients and additional points. If painting in Fitted mode is slow it might be better to fit the points, before they are passed to QwtPlotCurve.
- •
- Inverted
For Steps only. Draws a step function from the right to the left.
setCurveAttribute(),
testCurveAttribute(), curveFitter()
enum QwtPlotCurve::CurveStyle Curve styles.¶
- •
- 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(Yfx) or horizontal(Xfy) sticks 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 '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 NoStyle style and a symbol painting a point.
- •
- UserCurve
Styles >= UserCurve are reserved for derived classes of QwtPlotCurve that overload drawCurve() with additional application specific curve types.
setStyle(), style()
enum QwtPlotCurve::CurveType Curve type.¶
- •
- Yfx
Draws y as a function of x (the default). The baseline is interpreted as a horizontal line with y = baseline().
- •
- Xfy
Draws x as a function of y. The baseline is interpreted as a vertical line with x = baseline().
setCurveType(), curveType(),
baseline() brush()
enum QwtPlotItem::ItemAttribute [inherited] Plot Item Attributes¶
- •
- Legend
The item is represented on the legend.
- •
- AutoScale
The boundingRect() of the item is included in the autoscaling calculation.
setItemAttribute(),
testItemAttribute()
enum QwtPlotCurve::PaintAttribute Attributes to modify the drawing algorithm.¶
- •
- PaintFiltered
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 algos are implemented.
- •
- 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 ( especially on Windows ).
setPaintAttribute(),
testPaintAttribute()
enum QwtPlotItem::RenderHint [inherited]¶
Render hints.enum QwtPlotItem::RttiValues [inherited]¶
Runtime type information. RttiValues is used to cast plot items, without having to enable runtime type information of the compiler.Constructor & Destructor Documentation¶
QwtPlotCurve::QwtPlotCurve () [explicit]¶
Constructor.QwtPlotCurve::QwtPlotCurve (const QwtText &title) [explicit] Constructor¶
Parameters:title Title of the curve
QwtPlotCurve::QwtPlotCurve (const QString &title) [explicit] Constructor¶
Parameters:title Title of the curve
QwtPlotCurve::~QwtPlotCurve () [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:
QwtPlotItem::detach()
double QwtPlotCurve::baseline () const Return the value of the baseline¶
See also:setBaseline()
QwtDoubleRect QwtPlotCurve::boundingRect () const [virtual] Returns the bounding rectangle of the curve data. If there is no bounding rect, like for empty data the rectangle is invalid.¶
See also:QwtData::boundingRect(),
QwtDoubleRect::isValid()
const QBrush & QwtPlotCurve::brush () const¶
Return the brush used to fill the area between lines and the baseline. See also:setBrush(), setBaseline(),
baseline()
void QwtPlotCurve::closePolyline (const QwtScaleMap &xMap, const QwtScaleMap &yMap, QwtPolygon &pa) const [protected]¶
Complete a polygon to be a closed polygon including the area between the original polygon and the baseline. Parameters:xMap X map
yMap Y map
pa Polygon to be completed
int QwtPlotCurve::closestPoint (const QPoint &pos, double *dist = NULL) const 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 clostest 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
QwtCurveFitter * QwtPlotCurve::curveFitter () const Get the curve fitter. If curve fitting is disabled NULL is returned.¶
Returns:Curve fitter
QwtPlotCurve::CurveType QwtPlotCurve::curveType () const Return the curve type¶
See also:CurveType, setCurveType()
QwtData & QwtPlotCurve::data () [inline] Returns:¶
the the curve data
const QwtData & QwtPlotCurve::data () const [inline] Returns:¶
the the curve data
int QwtPlotCurve::dataSize () const Return the size of the data arrays¶
See also:setData()
void QwtPlotItem::detach () [inline, inherited]¶
This method detaches a QwtPlotItem from any QwtPlot it has been associated with. detach() is equivalent to calling attach( NULL ) See also:attach( QwtPlot* plot )
void QwtPlotCurve::draw (QPainter *painter, const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRect &canvasRect) const [virtual]¶
Draw the complete curve. Parameters:painter Painter
xMap Maps x-values into pixel coordinates.
yMap Maps y-values into pixel coordinates.
See also:
drawCurve(), drawSymbols()
void QwtPlotCurve::draw (QPainter *painter, const QwtScaleMap &xMap, const QwtScaleMap &yMap, intfrom, intto) const [virtual]¶
Draw an interval of the curve. Parameters:painter Painter
xMap maps x-values into pixel coordinates.
yMap maps y-values into pixel coordinates.
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(),
void QwtPlotCurve::draw (intfrom, intto) const¶
Draw a set of points of a curve. When observing an measurement while it is running, new points have to be added to an existing curve. drawCurve can be used to display them avoiding a complete redraw of the canvas. Setting plot()->canvas()->setAttribute(Qt::WA_PaintOutsidePaintEvent, true); will result in faster painting, if the paint engine of the canvas widget supports this feature. Parameters: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()
void QwtPlotCurve::drawCurve (QPainter *painter, intstyle, const QwtScaleMap &xMap, const QwtScaleMap &yMap, intfrom, intto) 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
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()
void QwtPlotCurve::drawDots (QPainter *painter, const QwtScaleMap &xMap, const QwtScaleMap &yMap, intfrom, intto) const [protected] Draw dots¶
Parameters:painter Painter
xMap x map
yMap y map
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()
void QwtPlotCurve::drawLines (QPainter *painter, const QwtScaleMap &xMap, const QwtScaleMap &yMap, intfrom, intto) const [protected]¶
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
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()
void QwtPlotCurve::drawSteps (QPainter *painter, const QwtScaleMap &xMap, const QwtScaleMap &yMap, intfrom, intto) const [protected] Draw step function¶
The direction of the steps depends on Inverted attribute. Parameters:painter Painter
xMap x map
yMap y map
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()
void QwtPlotCurve::drawSticks (QPainter *painter, const QwtScaleMap &xMap, const QwtScaleMap &yMap, intfrom, intto) const [protected] Draw sticks¶
Parameters:painter Painter
xMap x map
yMap y map
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()
void QwtPlotCurve::drawSymbols (QPainter *painter, const QwtSymbol &symbol, const QwtScaleMap &xMap, const QwtScaleMap &yMap, intfrom, intto) const [protected, virtual]¶
Draw symbols. Parameters:painter Painter
symbol Curve symbol
xMap x map
yMap y map
from index of the first point to be painted
to index of the last point to be painted
See also:
setSymbol(), draw(),
drawCurve()
void QwtPlotCurve::fillCurve (QPainter *painter, const QwtScaleMap &xMap, const QwtScaleMap &yMap, QwtPolygon &pa) const [protected] Fill the area between the curve and the baseline with the curve brush¶
Parameters:painter Painter
xMap x map
yMap y map
pa Polygon
See also:
setBrush(), setBaseline(),
setCurveType()
void QwtPlotItem::hide () [inherited]¶
Hide the item.void QwtPlotCurve::init () [protected]¶
Initialize data members.QwtDoubleRect QwtPlotItem::invTransform (const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRect &rect) const [inherited] Transform a rectangle from paint to scale coordinates¶
Parameters:xMap X map
yMap Y map
rect Rectangle in paint coordinates
Returns:
Rectangle in scale coordinates
See also:
transform()
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 is made for QwtPlotCurve and 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()
double QwtPlotCurve::maxXValue () const [inline]¶
boundingRect().right()double QwtPlotCurve::maxYValue () const [inline]¶
boundingRect().bottom()double QwtPlotCurve::minXValue () const [inline]¶
boundingRect().left()double QwtPlotCurve::minYValue () const [inline]¶
boundingRect().top()QRect 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 rect of the scale maps
const QPen & QwtPlotCurve::pen () const¶
Return the pen used to draw the lines. See also:setPen(), brush()
QwtPlot * QwtPlotItem::plot () const [inherited]¶
Return attached plot.int QwtPlotCurve::rtti () const [virtual] Returns:¶
QwtPlotItem::Rtti_PlotCurve
QwtDoubleRect 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 rect of the scale maps
void QwtPlotItem::setAxis (intxAxis, intyAxis) [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 QwtPlotCurve::setBaseline (doublereference)¶
Set the value of the baseline. The baseline is needed for filling the curve with a brush or the Sticks drawing style. The default value is 0.0. The interpretation of the baseline depends on the CurveType. With QwtPlotCurve::Yfx, the baseline is interpreted as a horizontal line at y = baseline(), with QwtPlotCurve::Yfy, it is interpreted as a vertical line at x = baseline(). Parameters:reference baseline
See also:
baseline(), setBrush(),
setStyle(), setCurveType()
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()
void QwtPlotCurve::setCurveAttribute (CurveAttributeattribute, boolon = true) Specify an attribute for drawing the curve¶
Parameters:attribute Curve attribute
on On/Off
/sa CurveAttribute, testCurveAttribute(), setCurveFitter()
void QwtPlotCurve::setCurveFitter (QwtCurveFitter *curveFitter) Assign a curve fitter setCurveFitter(NULL) disables curve fitting.¶
Parameters:curveFitter Curve fitter
void QwtPlotCurve::setCurveType (CurveTypecurveType) Assign the curve type¶
Parameters:curveType Yfx or Xfy
See also:
CurveType, curveType()
void QwtPlotCurve::setData (const QPolygonF &data) Initialize data with an array of points (explicitly shared).¶
Parameters:data Data
Note:
Internally the data is stored in a
QwtPolygonFData object
void QwtPlotCurve::setData (const QwtArray< double > &xData, const QwtArray< double > &yData) Initialize data with x- and y-arrays (explicitly shared) ( Builds an QwtArrayData object internally )¶
Parameters:xData x data
yData y data
Note:
Internally the data is stored in a
QwtArrayData object
void QwtPlotCurve::setData (const QwtData &data) Initialize data with a pointer to QwtData.¶
Parameters:data Data
See also:
QwtData::copy()
void QwtPlotCurve::setData (const double *xData, const double *yData, intsize) Set data by copying x- and y-values from specified memory blocks. Contrary to setCurveRawData(), 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
Note:
Internally the data is stored in a
QwtArrayData object
void QwtPlotItem::setItemAttribute (ItemAttributeattribute, boolon = true) [inherited] Toggle an item attribute¶
Parameters:attribute Attribute type
on true/false
See also:
testItemAttribute(),
ItemAttribute
void QwtPlotCurve::setPaintAttribute (PaintAttributeattribute, boolon = true) Specify an attribute how to draw the curve¶
Parameters:attribute Paint attribute
on On/Off /sa PaintAttribute, testPaintAttribute()
void QwtPlotCurve::setPen (const QPen &pen) Assign a pen¶
The width of non cosmetic pens is scaled according to the resolution of the paint device. Parameters:pen New pen
See also:
pen(), brush(),
QwtPainter::scaledPen()
void QwtPlotCurve::setRawData (const double *xData, const double *yData, intsize)¶
Initialize the data by pointing to memory blocks which are not managed by QwtPlotCurve. setRawData 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
Note:
Internally the data is stored in a
QwtCPointerData object
void QwtPlotItem::setRenderHint (RenderHinthint, boolon = true) [inherited] Toggle an render hint¶
Parameters:hint Render hint
on true/false
See also:
testRenderHint(),
RenderHint
void QwtPlotCurve::setStyle (CurveStylestyle) Set the curve's drawing style¶
Parameters:style Curve style
See also:
CurveStyle, style()
void QwtPlotCurve::setSymbol (const QwtSymbol &symbol)¶
Assign a symbol. Parameters:symbol Symbol
See also:
symbol()
void QwtPlotItem::setTitle (const QwtText &title) [inherited] Set a new title¶
Parameters:title Title
See also:
title()
void QwtPlotItem::setTitle (const QString &title) [inherited] Set a new title¶
Parameters:title Title
See also:
title()
void QwtPlotItem::setVisible (boolon) [virtual, inherited] Show/Hide the item¶
Parameters:on Show if true, otherwise hide
See also:
isVisible(), show(),
hide()
void QwtPlotItem::setXAxis (intaxis) [inherited] Set the X axis¶
The item will painted according to the coordinates its Axes. Parameters:axis X Axis
See also:
setAxis(), setYAxis(),
xAxis()
void QwtPlotItem::setYAxis (intaxis) [inherited] Set the Y axis¶
The item will painted according to the coordinates its Axes. Parameters:axis Y Axis
See also:
setAxis(), setXAxis(),
yAxis()
void QwtPlotItem::setZ (doublez) [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.QwtPlotCurve::CurveStyle QwtPlotCurve::style () const Return the current style¶
See also:CurveStyle, setStyle()
const QwtSymbol & QwtPlotCurve::symbol () const¶
Return the current symbol. See also:setSymbol()
bool QwtPlotCurve::testCurveAttribute (CurveAttributeattribute) const Returns:¶
true, if attribute is enabled
See also:
CurveAttribute,
setCurveAttribute()
bool QwtPlotItem::testItemAttribute (ItemAttributeattribute) const [inherited] Test an item attribute¶
Parameters:attribute Attribute type
Returns:
true/false
See also:
setItemAttribute(),
ItemAttribute
bool QwtPlotCurve::testPaintAttribute (PaintAttributeattribute) const¶
Return the current paint attributes. See also:PaintAttribute,
setPaintAttribute()
bool QwtPlotItem::testRenderHint (RenderHinthint) 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()
QRect QwtPlotItem::transform (const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QwtDoubleRect &rect) const [inherited] Transform a rectangle¶
Parameters:xMap X map
yMap Y map
rect Rectangle in scale coordinates
Returns:
Rectangle in paint coordinates
See also:
invTransform()
void QwtPlotCurve::updateLegend (QwtLegend *legend) const [virtual]¶
Update the widget that represents the curve on the legend. Reimplemented from QwtPlotItem.void QwtPlotItem::updateScaleDiv (const QwtScaleDiv &, const QwtScaleDiv &) [virtual, inherited]¶
Update the item to changes of the axes scale division. Update the item, when the axes of plot have changed. The default implementation does nothing, but items that depend on the scale division (like QwtPlotGrid()) have to reimplement updateScaleDiv() Parameters:xScaleDiv Scale division of the x-axis
yScaleDiv Scale division of the y-axis
See also:
QwtPlot::updateAxes()
double QwtPlotCurve::x (inti) const [inline] Parameters:¶
i index
Returns:
x-value at position i
int QwtPlotItem::xAxis () const [inherited]¶
Return xAxis.double QwtPlotCurve::y (inti) const [inline] Parameters:¶
i index
Returns:
y-value at position i
int QwtPlotItem::yAxis () const [inherited]¶
Return yAxis.double QwtPlotItem::z () const [inherited] Plot items are painted in increasing z-order.¶
Returns:setZ(),
QwtPlotDict::itemList()
Author¶
Generated automatically by Doxygen for Qwt User's Guide from the source code.Mon Aug 1 2011 | Version 5.2.2 |