QwtCPointerData(3) Qwt User's Guide QwtCPointerData(3)NAME
QwtCPointerData -
Data class containing two pointers to memory blocks of doubles.
SYNOPSIS
#include <qwt_data.h>
Inherits QwtData.
Public Member Functions
virtual QwtDoubleRect boundingRect () const
virtual QwtData * copy () const
QwtCPointerData & operator= (const QwtCPointerData &)
QwtCPointerData (const double *x, const double *y, size_t size)
virtual size_t size () const
virtual double x (size_t i) const
const double * xData () const
virtual double y (size_t i) const
const double * yData () const
Detailed Description
Data class containing two pointers to memory blocks of doubles.
Constructor &; Destructor Documentation
QwtCPointerData::QwtCPointerData (const double *x, const double *y, size_tsize) Constructor
Parameters:
x Array of x values
y Array of y values
size Size of the x and y arrays
Warning:
The programmer must assure that the memory blocks referenced by the pointers remain valid during the lifetime of the QwtPlotCPointer
object.
See also:
QwtPlotCurve::setData(), QwtPlotCurve::setRawData()
Member Function Documentation
QwtDoubleRect QwtCPointerData::boundingRect () const [virtual] Returns the bounding rectangle of the data. If there is no bounding rect, like
for empty data the rectangle is invalid: QwtDoubleRect::isValid() == false
Reimplemented from QwtData.
QwtData * QwtCPointerData::copy () const [virtual] Returns:
Pointer to a copy (virtual copy constructor)
Implements QwtData.
QwtCPointerData & QwtCPointerData::operator= (const QwtCPointerData &data)
Assignment.
size_t QwtCPointerData::size () const [virtual] Returns:
Size of the data set
Implements QwtData.
double QwtCPointerData::x (size_ti) const [virtual] Return the x value of data point i
Parameters:
i Index
Returns:
x X value of data point i
Implements QwtData.
const double * QwtCPointerData::xData () const Returns:
Array of the x-values
double QwtCPointerData::y (size_ti) const [virtual] Return the y value of data point i
Parameters:
i Index
Returns:
y Y value of data point i
Implements QwtData.
const double * QwtCPointerData::yData () const Returns:
Array of the y-values
Author
Generated automatically by Doxygen for Qwt User's Guide from the source code.
Version 5.2.2 Mon Aug 1 2011 QwtCPointerData(3)
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QwtRasterData(3) Qwt User's Guide QwtRasterData(3)NAME
QwtRasterData -
QwtRasterData defines an interface to any type of raster data.
SYNOPSIS
#include <qwt_raster_data.h>
Inherited by QwtPlotSpectrogram::PrivateData::DummyData.
Public Types
enum ConrecAttribute { IgnoreAllVerticesOnLevel = 1, IgnoreOutOfRange = 2 }
typedef QMap< double, QPolygonF > ContourLines
Public Member Functions
QwtDoubleRect boundingRect () const
virtual ContourLines contourLines (const QwtDoubleRect &rect, const QSize &raster, const QList< double > &levels, int flags) const
virtual QwtRasterData * copy () const =0
virtual void discardRaster ()
virtual void initRaster (const QwtDoubleRect &, const QSize &raster)
QwtRasterData ()
QwtRasterData (const QwtDoubleRect &)
virtual QwtDoubleInterval range () const =0
virtual QSize rasterHint (const QwtDoubleRect &) const
virtual void setBoundingRect (const QwtDoubleRect &)
virtual double value (double x, double y) const =0
virtual ~QwtRasterData ()
Detailed Description
QwtRasterData defines an interface to any type of raster data.
QwtRasterData is an abstract interface, that is used by QwtPlotRasterItem to find the values at the pixels of its raster.
Often a raster item is used to display values from a matrix. Then the derived raster data class needs to implement some sort of resampling,
that maps the raster of the matrix into the requested raster of the raster item ( depending on resolution and scales of the canvas ).
Member Enumeration Documentation
enum QwtRasterData::ConrecAttribute
Attribute to modify the contour algorithm.
Constructor &; Destructor Documentation
QwtRasterData::QwtRasterData ()
Constructor.
QwtRasterData::QwtRasterData (const QwtDoubleRect &boundingRect) Constructor
Parameters:
boundingRect Bounding rectangle
See also:
setBoundingRect()
QwtRasterData::~QwtRasterData () [virtual]
Destructor.
Member Function Documentation
QwtDoubleRect QwtRasterData::boundingRect () const Returns:
Bounding rectangle
See also:
boundingRect()
QwtRasterData::ContourLines QwtRasterData::contourLines (const QwtDoubleRect &rect, const QSize &raster, const QList< double > &levels,
intflags) const [virtual] Calculate contour lines
An adaption of CONREC, a simple contouring algorithm. http://local.wasp.uwa.edu.au/~pbourke/papers/conrec/
virtual QwtRasterData* QwtRasterData::copy () const [pure virtual]
Clone the data.
void QwtRasterData::discardRaster () [virtual]
Discard a raster. After the composition of an image QwtPlotSpectrogram calls discardRaster().
The default implementation does nothing, but if data has been loaded in initRaster(), it could deleted now.
See also:
initRaster(), value()
void QwtRasterData::initRaster (const QwtDoubleRect &, const QSize &raster) [virtual]
Initialize a raster. Before the composition of an image QwtPlotSpectrogram calls initRaster, announcing the area and its resolution that
will be requested.
The default implementation does nothing, but for data sets that are stored in files, it might be good idea to reimplement initRaster, where
the data is resampled and loaded into memory.
Parameters:
rect Area of the raster
raster Number of horizontal and vertical pixels
See also:
initRaster(), value()
virtual QwtDoubleInterval QwtRasterData::range () const [pure virtual] Returns:
the range of the values
QSize QwtRasterData::rasterHint (const QwtDoubleRect &) const [virtual]
Find the raster of the data for an area. The resolution is the number of horizontal and vertical pixels that the data can return for an
area. An invalid resolution indicates that the data can return values for any detail level.
The resolution will limit the size of the image that is rendered from the data. F.e. this might be important when printing a spectrogram to
a A0 printer with 600 dpi.
The default implementation returns an invalid resolution (size)
Parameters:
rect In most implementations the resolution of the data doesn't depend on the requested rectangle.
Returns:
Resolution, as number of horizontal and vertical pixels
void QwtRasterData::setBoundingRect (const QwtDoubleRect &boundingRect) [virtual] Set the bounding rect ( == area, un plot coordinates )
Parameters:
boundingRect Bounding rectangle
See also:
boundingRect()
virtual double QwtRasterData::value (doublex, doubley) const [pure virtual] Returns:
the value at a raster position
Parameters:
x X value in plot coordinates
y Y value in plot coordinates
Author
Generated automatically by Doxygen for Qwt User's Guide from the source code.
Version 5.2.2 Mon Aug 1 2011 QwtRasterData(3)