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QwtPlot Class Reference

A 2-D plotting widget. More...

#include <qwt_plot.h>

Inherits QFrame.

Inheritance diagram for QwtPlot

Inheritance graph
[legend]
List of all members.

Public Types

enum  {
  yLeft, yRight, xBottom, xTop,
  axisCnt
}

Public Methods

 QwtPlot (QWidget *p = 0, const char *name = 0)
 QwtPlot (const char *title, QWidget *p = 0, const char *name = 0)
virtual ~QwtPlot ()
void enableOutline (bool tf)
void setAutoReplot (bool tf = TRUE)
void setPlotBackground (const QColor &c)
void setPlotBorder (int bw)
void setOutlineStyle (Qwt::Shape os)
void setOutlinePen (const QPen &pn)
void setTitle (const char *t)
void setTitleFont (const QFont &f)
bool autoReplot () const
bool outlineEnabled () const
const QPen& outlinePen () const
Qwt::Shape outlineStyle () const
const QColor& plotBackground () const
int plotBorder () const
const QString& title () const
const QFont& titleFont () const
void clear ()
void print (QPrinter &p, const QwtColorFilter &cfilter = NoColorFilter)
long insertCurve (const char *title, int xAxis = xBottom, int yAxis = yLeft)
bool removeCurve (long key)
void removeCurves ()
bool setCurveBaseline (long key, double ref)
bool setCurveData (long key, double *x, double *y, int size)
bool setCurveData (long key, double *x, double *y, double *e, int size)
bool setCurveOptions (long key, int t)
bool setCurvePen (long key, const QPen &pen)
bool setCurveRawData (long key, double *x, double *y, int size)
bool setCurveRawData (long key, double *x, double *y, double *e, int size)
bool setCurveSplineSize (long key, int s)
bool setCurveStyle (long key, QwtCurve::CurveStyle s, int options = 0)
bool setCurveSymbol (long key, const QwtSymbol &s)
bool setCurveTitle (long key, const char *s)
bool setCurveXAxis (long key, int axis)
bool setCurveYAxis (long key, int axis)
long closestCurve (int xpos, int ypos, int &dist) const
long closestCurve (int xpos, int ypos, int &dist, double &xval, double &yval, int &index) const
double curveBaseline (long key) const
QArray<long> curveKeys () const
int curveOptions (long key) const
const QPen& curvePen (long key) const
int curveSplineSize (long key) const
QwtCurve::CurveStyle curveStyle (long key) const
const QwtSymbolcurveSymbol (long key) const
QString curveTitle (long key) const
int curveXAxis (long key) const
int curveYAxis (long key) const
void enableGridX (bool tf = TRUE)
void enableGridXMin (bool tf = TRUE)
void enableGridY (bool tf = TRUE)
void enableGridYMin (bool tf = TRUE)
void setGridXAxis (int axis)
void setGridYAxis (int axis)
void setGridPen (const QPen &p)
void setGridMajPen (const QPen &p)
void setGridMinPen (const QPen &p)
int gridXAxis () const
int gridYAxis () const
const QPen& gridMinPen ()
const QPen& gridMajPen ()
void changeAxisOptions (int axis, int opt, bool value)
void enableAxis (int axis, bool tf = TRUE)
void setAxisFont (int axis, const QFont &f)
void setAxisMargins (int axis, double mlo, double mhi)
void setAxisOptions (int axis, int opt)
void setAxisAutoScale (int axis)
void setAxisScale (int axis, double min, double max, double step = 0)
void setAxisLabelFormat (int axis, char f, int prec)
void setAxisTitleFont (int axis, const QFont &f)
void setAxisMaxMinor (int axis, int maxMinor)
void setAxisMaxMajor (int axis, int maxMajor)
void setAxisReference (int axis, double value)
void setAxisTitle (int axis, const char *t)
bool axisAutoScale (int axis) const
bool axisEnabled (int axis) const
const QFont axisFont (int axis)
bool axisMargins (int axis, double &mlo, double &mhi) const
int axisMaxMajor (int axis) const
int axisMaxMinor (int axis) const
int axisOptions (int axis) const
double axisReference (int axis) const
const QwtScaleDivaxisScale (int axis) const
void axisLabelFormat (int axis, char &f, int &prec) const
const QString& axisTitle (int axis) const
const QFont& axisTitleFont (int axis) const
double invTransform (int axis, int pos) const
int transform (int axis, double value) const
long insertMarker (const char *label = 0, int xAxis = xBottom, int yAxis = yLeft)
long insertLineMarker (const char *label, int axis)
bool removeMarker (long key)
void removeMarkers ()
long closestMarker (int xpos, int ypos, int &dist) const
bool setMarkerFont (long key, const QFont &f)
bool setMarkerLinePen (long key, const QPen &p)
bool setMarkerLineStyle (long key, QwtMarker::LineStyle st)
bool setMarkerPos (long key, double xval, double yVal)
bool setMarkerSymbol (long key, const QwtSymbol &s)
bool setMarkerLabel (long key, const char *txt)
bool setMarkerLabelAlign (long key, int align)
bool setMarkerLabelPen (long key, const QPen &p)
bool setMarkerXPos (long key, double val)
bool setMarkerYPos (long key, double val)
bool setMarkerPen (long key, const QPen &p)
bool setMarkerXAxis (long key, int axis)
bool setMarkerYAxis (long key, int axis)
const QFont& markerFont (long key) const
QArray<long> markerKeys () const
const QString& markerLabel (long key) const
int markerLabelAlign (long key) const
const QPen& markerLabelPen (long key) const
const QPen& markerLinePen (long key) const
QwtMarker::LineStyle markerLineStyle (long key) const
void markerPos (long key, double &mx, double &my) const
const QwtSymbolmarkerSymbol (long key) const
int markerXAxis (long key) const
int markerYAxis (long key) const
void enableLegend (bool tf)
void setLegendPos (int pos)
void setLegendFont (const QFont &f)
void setLegendFrameStyle (int st)
bool legendEnabled () const
int legendPos () const
int legendFrameStyle () const
const QFont legendFont () const

Public Slots

void replot ()
void updatePlot ()

Signals

void plotMousePressed (const QMouseEvent &e)
void plotMouseReleased (const QMouseEvent &e)
void plotMouseMoved (const QMouseEvent &e)
void legendClicked (long key)

Static Public Methods

bool axisValid (int axis)

Protected Methods

void redrawPixmap ()
void updateAxes ()
int verifyXAxis (int axis) const
int verifyYAxis (int axis) const
void resizeEvent (QResizeEvent *e)
void autoRefresh ()

Protected Attributes

QLabel* d_lblTitle
QwtPlotPixFrame* d_frmPlot
QwtScaled_scale [axisCnt]
QwtLegendd_legend
bool d_titleEnabled
QwtAutoScale d_as [axisCnt]
QwtDiMap d_map [axisCnt]
QwtScaleDiv d_sdiv [axisCnt]
QwtPlotGrid d_grid
int d_axisEnabled [axisCnt]
int d_legendEnabled
int d_legendPos
int d_plotBorder
QwtCurveDict* d_curves
QwtMarkerDict* d_markers
int d_axisDist
int d_borderDist
int d_hScaleDist
int d_vScaleDist
int d_titleDist
int d_margin
int d_autoReplot

Friends

class  QwtPlotItem
class  QwtPlotPixFrame

Detailed Description

A 2-D plotting widget.

QwtPlot is a widget for plotting two-dimensional graphs. An unlimited number of data pairs can be displayed as curves in different styles and colors. A plot can have up to four axes, with each curve attached to an x- and a y axis. The scales at the axes are dimensioned automatically using an algorithm which can be configured separately for each axis. Linear and logarithmic scaling is supported. Markers of different styles can be added to the plot.

Curves and markers are identified by unique keys which are generated automatically when a curve or a marker is created. These keys are used to access the properties of the corresponding curves and markers.

A QwtPlot widget can have up to four axes which are indexed by the constants QwtPlot::yLeft, QwtPlot::yRight, QwtPlot::xTop, and QwtPlot::xBottom. Curves, markers, and the grid must be attached to an x axis and a y axis (Default: yLeft and xBottom).

Example
The following example shows (schematically) the most simple way to use QwtPlot. By default, only the left and bottom axes are visible and their scales are computed automatically.
#include "../include/qwt_plot.h>

QwtPlot *myPlot;
long curve1, curve2;                    // keys
double x[100], y1[100], y2[100];        // x and y values

myPlot = new QwtPlot("Two Graphs", parent, name);

// add curves
curve1 = myPlot->insertCurve("Graph 1");
curve2 = myPlot->insertCurve("Graph 2");

getSomeValues(x, y1, y2);

// copy the data into the curves
myPlot->setCurveData(curve1, x, y1, 100);
myPlot->setCurveData(curve2, x, y2, 100);

// finally, refresh the plot
myPlot->replot();


Constructor & Destructor Documentation

QwtPlot::QwtPlot ( QWidget * p = 0,
const char * name = 0 )
 

Constructor.

QwtPlot::QwtPlot ( const char * title,
QWidget * p = 0,
const char * name = 0 )
 

Constructor.

Parameters:
title   Title text
parent   Parent widget
name   Widget name

QwtPlot::~QwtPlot ( ) [virtual]
 

Destructor.


Member Function Documentation

bool QwtPlot::autoReplot ( ) const
 

Returns:
TRUE if the autoReplot option is set.

bool QwtPlot::axisAutoScale ( int axis ) const
 

Returns:
TRUE if autoscaling is enabled
Parameters:
axis   axis index

bool QwtPlot::axisEnabled ( int axis ) const
 

Returns:
TRUE if a specified axis is enabled
Parameters:
axis   axis index

const QFont QwtPlot::axisFont ( int axis )
 

Returns:
the font of the scale labels for a specified axis
Parameters:
axis   axis index

void QwtPlot::axisLabelFormat ( int axis,
char & f,
int & prec ) const
 

Returns:
the number format for the major scale labels of a specified axis
Parameters:
axis   axis index
Return values:
f   format character
prec   precision

bool QwtPlot::axisMargins ( int axis,
double & mlo,
double & mhi ) const
 

Determine the scale margins for a specified axis.

Parameters:
axis   axis index
Return values:
mlo   Margin at the lower limit
mhi   Margin at the upper limit
See also:
QwtAutoScale::margins()

int QwtPlot::axisMaxMajor ( int axis ) const
 

Returns:
the maximum number of major ticks for a specified axis
Parameters:
axis   axis index

int QwtPlot::axisMaxMinor ( int axis ) const
 

Returns:
the maximum number of minor ticks for a specified axis
Parameters:
axis   axis index

int QwtPlot::axisOptions ( int axis ) const
 

Returns:
the autoscaling options of a specified axis
Parameters:
axis   axis index
See also:
QwtAutoScale::options

double QwtPlot::axisReference ( int axis ) const
 

The reference value is needed if the autoscaling options QwtAutoScale::Symmetric or QwtAutoScale::IncludeRef are set.

Returns:
the reference value of an axis
Parameters:
axis   axis index
See also:
QwtAutoScale, QwtPlot::setAxisOptions

const QwtScaleDiv & QwtPlot::axisScale ( int axis ) const
 

Returns:
the scale division of a specified axis
Parameters:
axis   axis index
See also:
QwtScaleDiv

const QString & QwtPlot::axisTitle ( int axis ) const
 

Returns:
the title of a specified axis
Parameters:
axis   axis index

const QFont & QwtPlot::axisTitleFont ( int axis ) const
 

Returns:
the title font of a specified axis
Parameters:
axis   axis index

bool QwtPlot::axisValid ( int axis ) [static]
 

Returns:
TRUE if the specified axis exists, otherwise FALSE
Parameters:
axis   axis index

void QwtPlot::changeAxisOptions ( int axis,
int opt,
bool value )
 

Change specified autoscaling options of an axis.

Parameters:
axis   axis index
opt   Set of or'ed options
value   Value to be assigned to all the specified options (TRUE or FALSE)
See also:
QwtAutoScale::changeAxisOptions

void QwtPlot::clear ( )
 

Remove all curves and markers.

long QwtPlot::closestCurve ( int xpos,
int ypos,
int & dist,
double & xval,
double & yval,
int & index ) const
 

Find the curve which is closest to a point in the plotting area.

Determines the position and index of the closest data point.

Parameters:
xpos  
ypos   coordinates of a point in the plotting region
Return values:
xval  
yvalvalues   of the closest point in the curve's data array
dist   -- distance in points between (xpos, ypos) and the closest data point
index   -- index of the closest point in the curve's data array
Returns:
Key of the closest curve or 0 if no curve was found.

long QwtPlot::closestCurve ( int xpos,
int ypos,
int & dist ) const
 

Find the curve which is closest to a specified point in the plotting area.

Parameters:
xpos  
ypos   position in the plotting region
Return values:
dist   distance in points between (xpos, ypos) and the closest data point
Returns:
Key of the closest curve or 0 if no curve was found.

long QwtPlot::closestMarker ( int xpos,
int ypos,
int & dist ) const
 

Find the marker which is closest to a given point.

Parameters:
xpos  
ypos   coordinates of a point in the plotting region
Return values:
dist   Distance in points between the marker and the specified point.
Returns:
Key of the closest marker or 0 if no marker was found

double QwtPlot::curveBaseline ( long key ) const
 

Return the baseline offset for a specified curve.

Parameters:
key   curve key
Returns:
Baseline offset of the specified curve, or 0 if the curve doesn't exist
See also:
setCurveBaseline()

QArray< long > QwtPlot::curveKeys ( ) const
 

Returns:
an array containing the keys of all curves

int QwtPlot::curveOptions ( long key ) const
 

Returns:
the drawing options of the curve indexed by key
Parameters:
key   Key of the curve

const QPen & QwtPlot::curvePen ( long key ) const
 

Returns:
the pen of the curve indexed by key
Parameters:
key   Key of the curve

int QwtPlot::curveSplineSize ( long key ) const
 

Returns:
the spline size of the curve indexed by key
Parameters:
key   Key of the curve

QwtCurve::CurveStyle QwtPlot::curveStyle ( long key ) const
 

Returns:
the style of the curve indexed by key
Parameters:
key   Key of the curve
See also:
setCurveStyle()

const QwtSymbol & QwtPlot::curveSymbol ( long key ) const
 

the symbol of the curve indexed by key.

Parameters:
key   Key of the curve
Returns:
The symbol of the specified curve. If the key is invalid, a symbol of type 'NoSymbol'.

QString QwtPlot::curveTitle ( long key ) const
 

Returns:
the title of the curve indexed by key
Parameters:
key   Key of the curve

int QwtPlot::curveXAxis ( long key ) const
 

Return the index of the x axis to which a curve is mapped.

Parameters:
key   Key of the curve
Returns:
x axis of the curve or -1 if the key is invalid.

int QwtPlot::curveYAxis ( long key ) const
 

the index of the y axis to which a curve is mapped.

Parameters:
key   Key of the curve
Returns:
y axis of the curve or -1 if the key is invalid.

void QwtPlot::enableAxis ( int axis,
bool tf = TRUE )
 

Enable or disable a specified axis.

When an axis is disabled, this only means that it is not visible on the screen. Curves, markers and can be attached to disabled axes, and transformation of screen coordinates into values works as normal.

Only xBottom and yLeft are enabled by default.

Parameters:
axis   axis index
tf   TRUE (enabled) or FALSE (disabled)

void QwtPlot::enableGridX ( bool tf = TRUE )
 

Enable or disable vertical gridlines.

Parameters:
tf   Enable (TRUE) or disable (FALSE). Defaults to TRUE.

void QwtPlot::enableGridXMin ( bool tf = TRUE )
 

Enable or disable vertical gridlines for the minor scale marks.

Parameters:
tf   enable (TRUE) or disable (FALSE). Defaults to TRUE.

void QwtPlot::enableGridY ( bool tf = TRUE )
 

Enable or disable horizontal gridlines.

Parameters:
tf   Enable (TRUE) or disable (FALSE). Defaults to TRUE.

void QwtPlot::enableGridYMin ( bool tf = TRUE )
 

Enable or disable horizontal gridlines for the minor scale marks.

Parameters:
tf   enable (TRUE) or disable (FALSE). Defaults to TRUE.

void QwtPlot::enableLegend ( bool tf )
 

Enable or disable the legend.

Parameters:
tf   TRUE (enabled) or FALSE (disabled)
See also:
QwtPlot::setLegendPos()

void QwtPlot::enableOutline ( bool tf )
 

Enables or disables outline drawing. When the outline feature is enabled, a shape will be drawn in the plotting region when the user presses or drags the mouse. It can be used to implement crosshairs, mark a selected region, etc.

Parameters:
tf   TRUE (enabled) or FALSE (disabled)
Warning:
An outline style has to be specified.
See also:
setOutlineStyle()

long QwtPlot::insertCurve ( const char * title,
int xAxis = xBottom,
int yAxis = yLeft )
 

Insert a new curve and return a unique key.

Parameters:
title   title of the new curve
xAxis   x axis to be attached. Defaults to xBottom.
yAxis   y axis to be attached. Defaults to yLeft.
Returns:
The key of the new curve or 0 if no new key could be found or if no new curve could be allocated.

long QwtPlot::insertLineMarker ( const char * label,
int axis )
 

This function is a shortcut to insert a horizontal or vertical line marker, dependent on the specified axis.

Parameters:
label   Label
axis   Axis to be attached
Returns:
New key if the marker could be inserted, 0 if not.

long QwtPlot::insertMarker ( const char * label = 0,
int xAxis = xBottom,
int yAxis = yLeft )
 

Insert a new marker.

Parameters:
label   Label
xAxis   X axis to be attached
yAxis   Y axis to be attached

double QwtPlot::invTransform ( int axis,
int pos ) const
 

Transform the x or y coordinate of a position in the drawing region into a value.

Parameters:
axis   axis index
pos   position
Warning:
The position can be an x or a y coordinate, depending on the specified axis.

void QwtPlot::legendClicked ( long key ) [signal]
 

A signal which is emitted when the user has clicked on a legend item.

Parameters:
key   Key of the curve corresponding to the selected legend item

const QFont QwtPlot::legendFont ( ) const
 

Returns:
the font of the legend items

int QwtPlot::legendFrameStyle ( ) const
 

Returns:
the frame style of the legend

const QFont & QwtPlot::markerFont ( long key ) const
 

Returns:
the font of a marker

QArray< long > QwtPlot::markerKeys ( ) const
 

Returns:
an array containing the keys of all markers

const QString & QwtPlot::markerLabel ( long key ) const
 

Returns:
a marker's label
Parameters:
key   Marker key

int QwtPlot::markerLabelAlign ( long key ) const
 

Returns:
a marker's label alignment
Parameters:
key   Marker key

const QPen & QwtPlot::markerLabelPen ( long key ) const
 

Returns:
the pen of a marker's label
Parameters:
key   Marker key

const QPen & QwtPlot::markerLinePen ( long key ) const
 

Returns:
a marker's line pen
Parameters:
key   Marker key

QwtMarker::LineStyle QwtPlot::markerLineStyle ( long key ) const
 

Returns:
a marker's line style
Parameters:
key   Marker key

void QwtPlot::markerPos ( long key,
double & mx,
double & my ) const
 

Get the position of a marker.

Parameters:
key   Marker key
Return values:
mx  
my   Marker position

const QwtSymbol & QwtPlot::markerSymbol ( long key ) const
 

Returns:
a marker's symbol
Parameters:
key   Marker key

int QwtPlot::markerXAxis ( long key ) const
 

Returns:
the x axis to which a marker is attached
Parameters:
key   Marker key

int QwtPlot::markerYAxis ( long key ) const
 

Returns:
the y axis to which a marker is attached
Parameters:
key   Marker key

bool QwtPlot::outlineEnabled ( ) const
 

Returns:
TRUE if the outline feature is enabled

const QPen & QwtPlot::outlinePen ( ) const
 

Returns:
the pen used to draw outlines

Qwt::Shape QwtPlot::outlineStyle ( ) const
 

Returns:
the outline style
See also:
setOutlineStyle()

const QColor & QwtPlot::plotBackground ( ) const
 

Returns:
the background color of the plotting area

int QwtPlot::plotBorder ( ) const
 

Returns:
the border width of the plotting area

void QwtPlot::plotMouseMoved ( const QMouseEvent & e ) [signal]
 

A signal which is emitted when the mouse is moved in the plotting area.

Parameters:
e   Mouse event object, event coordinates referring to the plotting area

void QwtPlot::plotMousePressed ( const QMouseEvent & e ) [signal]
 

A signal which is emitted when the mouse is pressed in the plotting area.

Parameters:
e   Mouse event object, event coordinates referring to the plotting area

void QwtPlot::plotMouseReleased ( const QMouseEvent & e ) [signal]
 

A signal which is emitted when a mouse button has been released in the plotting area.

Parameters:
e   Mouse event object, event coordinates referring to the plotting area

void QwtPlot::print ( QPrinter & pr,
const QwtColorFilter & cfilter = NoColorFilter )
 

Print the plot to a QPrinter This function prints the contents of a QwtPlot instance to QPrinter object. The printed output is independent of the widget displayed on the screen.

Parameters:
prThe   printer
cfilter   color filter for curves and markers
Warning:
  • The background of the plot is not printed.
  • Scales and titles are always printed in black color.
  • major gridlines are printed in dark gray; minor gridlines are printed in gray.
  • Curves, markers, symbols, etc. are printed in their screen colors if no color filter is specified. A color filter may be useful if curves have bright colors (which would be hardly visible), or if a grayscale output is desired.
  • Font sizes and line widths are not scaled.
  • The size of the printed plot is determined automatically, dependent on the page size.
Example
myPlot->print(printer);                  // screen colors
myPlot->print(printer, QwtFltrDim(200)); // colors darkened
myPlot->print(printer, QwtFltrInv());    // colors inverted
  
Bugs and limitations:
  • The legend is not printed.
  • QPrinter has some bugs in Qt 1.2 (see Qt manual on QPrinter).
See also:
QwtColorFilter

bool QwtPlot::removeCurve ( long key )
 

remove the curve indexed by key.

Parameters:
key   Key of the curve

void QwtPlot::removeCurves ( )
 

Remove all curves.

bool QwtPlot::removeMarker ( long key )
 

Remove the marker indexed by key.

Parameters:
key   unique key

void QwtPlot::removeMarkers ( )
 

Remove all markers.

void QwtPlot::replot ( ) [slot]
 

Redraw the plot If the autoReplot option is not set (which is the default) or if any curves are attached to raw data, the plot has to be refreshed explicitly in order to make changes visible.

See also:
setAutoReplot()

void QwtPlot::setAutoReplot ( bool tf = TRUE )
 

Set or reset the autoReplot option If the autoReplot option is set, the plot will be updated implicitly by manipulating member functions. Since this may be time-consuming, it is recommended to leave this option switched off and call replot() explicitly if necessary.

The autoReplot option is set to FALSE by default, which means that the user has to call replot() in order to make changes visible.

Parameters:
tf   TRUE or FALSE. Defaults to TRUE.
See also:
replot()

void QwtPlot::setAxisAutoScale ( int axis )
 

Enable autoscaling for a specified axis.

This member function is used to switch back to autoscaling mode after a fixed scale has been set. Autoscaling is enabled by default.

Parameters:
axis   axis index
See also:
setAxisScale()

void QwtPlot::setAxisFont ( int axis,
const QFont & f )
 

Change the font of an axis.

Parameters:
axis   axis index
f   font
Warning:
This function changes the font of the tick labels, not of the axis title.

void QwtPlot::setAxisLabelFormat ( int axis,
char f,
int prec )
 

Change the number format for the major scale of a selected axis.

Parameters:
axis   axis index
f   format
prec   precision

void QwtPlot::setAxisMargins ( int axis,
double mlo,
double mhi )
 

Assign margins to a specified axis.

Parameters:
axis   axis index
mlo   margin at the lower end of the scale
mhi   margin at the upper end of the scale
Warning:
If the scale is logarithmic, the margins are measured in decades
See also:
QwtAutoScale::setMargins

void QwtPlot::setAxisMaxMajor ( int axis,
int maxMajor )
 

Set the maximum number of major scale intervals for a specified axis.

Parameters:
axis   axis index
maxMajor   maximum number of major steps
See also:
QwtAutoScale::setMaxMajor

void QwtPlot::setAxisMaxMinor ( int axis,
int maxMinor )
 

Set the maximum number of minor scale intervals for a specified axis.

Parameters:
axis   axis index
maxMinor   maximum number of minor steps
See also:
QwtAutoScale::setMaxMinor

void QwtPlot::setAxisOptions ( int axis,
int opt )
 

Reset scale options and set specified options for a specified axis.

Parameters:
axis   axis index
opt   set of options
See also:
QwtAutoScale::setOptions

void QwtPlot::setAxisReference ( int axis,
double value )
 

Set a reference value for a specified axis.

The reference value is used by some autoscaling modes.

Parameters:
axis   axis index
value   reference value
See also:
QwtAutoScale::setReference, setAxisOptions()

void QwtPlot::setAxisScale ( int axis,
double min,
double max,
double step = 0 )
 

Disable autoscaling and specify a fixed scale for a selected axis.

Parameters:
axis   axis index
min  
max   minimum and maximum of the scale
step   Major step size. If step == 0, the step size is calculated automatically using the maxMajor setting.
See also:
setAxisMaxMajor()

void QwtPlot::setAxisTitle ( int axis,
const char * t )
 

Change the title of a specified axis.

Parameters:
axis   axis index
t   axis title

void QwtPlot::setAxisTitleFont ( int axis,
const QFont & f )
 

Change the title font of a selected axis.

Parameters:
axis   axis index
f   font

bool QwtPlot::setCurveBaseline ( long key,
double ref )
 

Set the baseline for a specified curve.

The baseline is needed for the curve style QwtCurve::Sticks,

Parameters:
key   curve key
ref   baseline offset from zero
See also:
QwtCurve::setBaseline

bool QwtPlot::setCurveData ( long key,
double * xdat,
double * ydat,
int size )
 

Assign x and y values to a curve. In opposite to @QwtPlot::setCurveRawData@, this function makes a 'deep copy' of the data.

Parameters:
key   curve key
xdat   pointer to x values
ydat   pointer to y values
size   size of xdat and ydat
See also:
setCurveRawData(), QwtCurve::setData

bool QwtPlot::setCurveOptions ( long key,
int opt )
 

Set the style options of a curve indexed by key.

Parameters:
key   The curve's key
opt   The type of the spline
Returns:
TRUE if the specified curve exists.
See also:
QwtCurve::setOptions for a detailed description of valid options.

bool QwtPlot::setCurvePen ( long key,
const QPen & pen )
 

Assign a pen to a curve indexed by key.

Parameters:
key   Key of the curve
pen   new pen
Returns:
TRUE if the curve exists

bool QwtPlot::setCurveRawData ( long key,
double * xdat,
double * ydat,
double * edat,
int size )
 

bool QwtPlot::setCurveRawData ( long key,
double * xdat,
double * ydat,
int size )
 

Attach a curve to the specified arrays without copying.

This function does not copy the values of the specified arrays. Removing the curve will not delete the data.

Parameters:
key   Key of the curve
xdat  
ydat   Pointers to x and y data
size   size of ydat and ydat
Returns:
TRUE if the curve exists
Warning:
Don't delete dynamically allocated data while a curve is attached to them.
See also:
setCurveData(), QwtCurve::setRawData

bool QwtPlot::setCurveSplineSize ( long key,
int s )
 

Set the number of interpolated points of a curve indexed by key.

Parameters:
key   key of the curve
s   size of the spline
Returns:
TRUE if the curve exists

bool QwtPlot::setCurveStyle ( long key,
QwtCurve::CurveStyle s,
int options = 0 )
 

Change a curve's style.

Parameters:
key   Key of the curve
s   display style of the curve
options   style options
Returns:
TRUE if the curve exists
See also:
QwtCurve::setStyle() for a detailed description of valid styles.

bool QwtPlot::setCurveSymbol ( long key,
const QwtSymbol & s )
 

Assign a symbol to a curve indexed by key.

Parameters:
key   Key of the curve
s  
Returns:
TRUE if the curve exists

bool QwtPlot::setCurveTitle ( long key,
const char * s )
 

Parameters:
key  
s  

bool QwtPlot::setCurveXAxis ( long key,
int axis )
 

Attach a curve to an x axis.

Parameters:
key   key of the curve
axis   x axis to be attached

bool QwtPlot::setCurveYAxis ( long key,
int axis )
 

Attach a curve to an y axis.

Parameters:
key   key of the curve
axis   y axis to be attached

void QwtPlot::setGridMajPen ( const QPen & p )
 

Change the pen for the major gridlines.

Parameters:
p   new pen

void QwtPlot::setGridMinPen ( const QPen & p )
 

Change the pen for the minor gridlines.

Parameters:
p   new pen

void QwtPlot::setGridPen ( const QPen & p )
 

Change the grid's pens for major and minor gridlines.

Parameters:
p   new pen

void QwtPlot::setGridXAxis ( int axis )
 

Attach the grid to an x axis.

Parameters:
axis   x axis to be attached

void QwtPlot::setGridYAxis ( int axis )
 

Attach the grid to an y axis.

Parameters:
axis   y axis to be attached

void QwtPlot::setLegendFont ( const QFont & f )
 

Change the font of the legend items.

Parameters:
fnew   font

void QwtPlot::setLegendFrameStyle ( int st )
 

Change the legend's frame style.

Parameters:
stFrame   Style. See Qt manual on QFrame.

void QwtPlot::setLegendPos ( int pos )
 

Specify the position of the legend within the widget.

Parameters:
pos   The legend's position. Valid values are Qwt::Left, Qwt::Right, Qwt::Top, QwtBottom.

bool QwtPlot::setMarkerFont ( long key,
const QFont & f )
 

Specify a font for a marker's label.

Parameters:
key   Marker key
f   New font
Returns:
TRUE if the specified marker exists

bool QwtPlot::setMarkerLabel ( long key,
const char * txt )
 

Assign a label to a marker.

Parameters:
key   Marker key
txt   Label text
Returns:
TRUE if the specified marker exists

bool QwtPlot::setMarkerLabelAlign ( long key,
int align )
 

Specify the alignment of a marker's label.

The alignment determines the position of the label relative to the marker's position. The default setting is AlignCenter.

Parameters:
key   Marker key
align   Alignment: AlignLeft, AlignRight, AlignTop, AlignBottom, AlignHCenter, AlignVCenter, AlignCenter or a combination of them.
Returns:
TRUE if the specified marker exists

bool QwtPlot::setMarkerLabelPen ( long key,
const QPen & p )
 

Specify a pen for a marker's label.

Parameters:
key   Marker key
p   Label pen
Returns:
TRUE if the specified marker exists

bool QwtPlot::setMarkerLinePen ( long key,
const QPen & p )
 

Specify a pen for a marker's line.

Parameters:
key   Marker key
p   New pen
Returns:
TRUE if the specified marker exists

bool QwtPlot::setMarkerLineStyle ( long key,
QwtMarker::LineStyle st )
 

Specify the line style for a marker.

Parameters:
key   Marker key
st   Line style: QwtMarker::HLine, QwtMarker::VLine, QwtMarker::NoLine or a combination of them.
Returns:
TRUE if the specified marker exists

bool QwtPlot::setMarkerPen ( long key,
const QPen & p )
 

Specify a pen for a marker's label.

Parameters:
key   Marker key
p   New pen
Returns:
TRUE if the specified marker exists

bool QwtPlot::setMarkerPos ( long key,
double xval,
double yval )
 

Change the position of a marker.

Parameters:
key   Marker key
xval  
yval   Position of the marker in axis coordinates.
Returns:
TRUE if the specified marker exists

bool QwtPlot::setMarkerSymbol ( long key,
const QwtSymbol & s )
 

Assign a symbol to a specified marker.

Parameters:
key   Marker key
s   new symbol
Returns:
TRUE if the specified marker exists

bool QwtPlot::setMarkerXAxis ( long key,
int axis )
 

Attach the marker to an x axis.

Returns:
TRUE if the specified marker exists.

bool QwtPlot::setMarkerXPos ( long key,
double val )
 

Specify the X position of a marker.

Parameters:
key   Marker key
val   X position of the marker
Returns:
TRUE if the specified marker exists

bool QwtPlot::setMarkerYAxis ( long key,
int axis )
 

Attach the marker to a Y axis.

Parameters:
key   Marker key
axis   Axis to be attached
Returns:
TRUE if the specified marker exists

bool QwtPlot::setMarkerYPos ( long key,
double val )
 

Specify the Y position of the marker.

Parameters:
key   Marker key
val   Y position of the marker
Returns:
TRUE if the specified marker exists

void QwtPlot::setOutlinePen ( const QPen & pn )
 

Specify a pen for the outline.

Parameters:
pn   new pen

void QwtPlot::setOutlineStyle ( Qwt::Shape os )
 

Specify the style of the outline.

The outline style determines which kind of shape is drawn in the plotting region when the user presses a mouse button or drags the mouse. Valid Styles are:

Parameters:
os   Outline Style. Valid values are: Qwt::HLine, Qwt::VLine, Qwt::Cross, Qwt::Rectangle, Qwt::Ellipse
Qwt::Cros
Cross hairs are drawn across the plotting area when the user presses a mouse button. The lines intersect at the point where the mouse was pressed and move with the mouse pointer.
Qwt::HLine, Qwt::VLine
A horizontal or vertical line appears when the user presses a mouse button. This is useful for moving line markers.
Qwt::Rectangle
A rectangle is displayed when the user drags the mouse. One corner is fixed at the point where the mouse was pressed, and the opposite corner moves with the mouse pointer. This can be used for selecting regions.
Qwt::Ellipse
Similar to Qwt::Rectangle, but with an ellipse inside a bounding rectangle.
See also:
enableOutline()

void QwtPlot::setPlotBackground ( const QColor & c )
 

Change the background of the plotting area.

Parameters:
c   new background color

void QwtPlot::setPlotBorder ( int w )
 

Change the border width of the plotting area.

Parameters:
w   new border width

void QwtPlot::setTitle ( const char * t )
 

Change the plot's title.

Parameters:
t   new title

void QwtPlot::setTitleFont ( const QFont & f )
 

Change the title font.

Parameters:
f   new title font

int QwtPlot::transform ( int axis,
double value ) const
 

Transform a value into a coordinate in the plotting region.

Parameters:
axis   axis index
value   value
Returns:
X or y coordinate in the plotting region corresponding to the value.

void QwtPlot::updateAxes ( ) [protected]
 

Rebuild the scales and maps.

int QwtPlot::verifyXAxis ( int axis ) const [protected]
 

Check if an index is a valid x axis.

Parameters:
axis   axis index
Returns:
its input value if the specified axis is an x axis; the default x axis if not.

int QwtPlot::verifyYAxis ( int axis ) const [protected]
 

Checks if an integer is a valid index for a y axis.

Parameters:
axis   axis index
Returns:
its input value if the specified axis is an x axis; the default x axis if not.


The documentation for this class was generated from the following files:
Generated at Thu Dec 14 00:27:19 2000 for Qwt User's Guide by doxygen1.2.3 written by Dimitri van Heesch, © 1997-2000