qwt_data.cpp

/* -*- mode: C++ ; c-file-style: "stroustrup" -*- *****************************
 * Qwt Widget Library
 * Copyright (C) 1997   Josef Wilgen
 * Copyright (C) 2002   Uwe Rathmann
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the Qwt License, Version 1.0
 *****************************************************************************/

#include "qwt_math.h"
#include "qwt_data.h"

//! Constructor
QwtData::QwtData()
{
}

//! Destructor
QwtData::~QwtData()
{
}

/*!
  Returns the bounding rectangle of the data. If there is
  no bounding rect, like for empty data the rectangle is invalid:
  QwtDoubleRect::isValid() == false

  \warning This is an slow implementation iterating over all points. 
           It is intended to be overloaded by derived classes. In case of
           auto scaling boundingRect() is called for every replot, so it 
           might be worth to implement a cache, or use x(0), x(size() - 1)
           for ordered data ...
*/
QwtDoubleRect QwtData::boundingRect() const
{
    const size_t sz = size();

    if ( sz <= 0 )
        return QwtDoubleRect(1.0, 1.0, -2.0, -2.0); // invalid

    double minX, maxX, minY, maxY;
    minX = maxX = x(0);
    minY = maxY = y(0);

    for ( size_t i = 1; i < sz; i++ )
    {
        const double xv = x(i);
        if ( xv < minX )
            minX = xv;
        if ( xv > maxX )
            maxX = xv;

        const double yv = y(i);
        if ( yv < minY )
            minY = yv;
        if ( yv > maxY )
            maxY = yv;
    }
    return QwtDoubleRect(minX, minY, maxX - minX, maxY - minY);
}

/*!
  Constructor

  \param polygon Polygon data
  \sa QwtPlotCurve::setData()
*/
#if QT_VERSION >= 0x040000
QwtPolygonFData::QwtPolygonFData(const QPolygonF &polygon):
#else
QwtPolygonFData::QwtPolygonFData(const QwtArray<QwtDoublePoint> &polygon):
#endif
    d_data(polygon)
{
}

//! Assignment 
QwtPolygonFData& QwtPolygonFData::operator=(
    const QwtPolygonFData &data)
{
    if (this != &data)
    {
        d_data = data.d_data;
    }
    return *this;
}

//! \return Size of the data set 
size_t QwtPolygonFData::size() const 
{ 
    return d_data.size(); 
}

/*!
  Return the x value of data point i

  \param i Index
  \return x X value of data point i
*/
double QwtPolygonFData::x(size_t i) const 
{ 
    return d_data[int(i)].x(); 
}

/*!
  Return the y value of data point i

  \param i Index
  \return y Y value of data point i
*/
double QwtPolygonFData::y(size_t i) const 
{ 
    return d_data[int(i)].y(); 
}

#if QT_VERSION >= 0x040000
const QPolygonF &QwtPolygonFData::data() const
#else
const QwtArray<QwtDoublePoint> &QwtPolygonFData::data() const
#endif
{
    return d_data;
}

/*!
  \return Pointer to a copy (virtual copy constructor)
*/
QwtData *QwtPolygonFData::copy() const 
{ 
    return new QwtPolygonFData(d_data); 
}

/*!
  Constructor

  \param x Array of x values
  \param y Array of y values
  
  \sa QwtPlotCurve::setData
*/
QwtArrayData::QwtArrayData(
        const QwtArray<double> &x, const QwtArray<double> &y): 
    d_x(x), 
    d_y(y)
{
}

/*!
  Constructor
  
  \param x Array of x values
  \param y Array of y values
  \param size Size of the x and y arrays
  \sa QwtPlotCurve::setData
*/
QwtArrayData::QwtArrayData(const double *x, const double *y, size_t size)
{
#if QT_VERSION >= 0x040000
    d_x.resize(size);
    qMemCopy(d_x.data(), x, size * sizeof(double));

    d_y.resize(size);
    qMemCopy(d_y.data(), y, size * sizeof(double));
#else
    d_x.detach();
    d_x.duplicate(x, size);

    d_y.detach();
    d_y.duplicate(y, size);
#endif
}

//! Assignment 
QwtArrayData& QwtArrayData::operator=(const QwtArrayData &data)
{
    if (this != &data)
    {
        d_x = data.d_x;
        d_y = data.d_y;
    }
    return *this;
}

//! \return Size of the data set 
size_t QwtArrayData::size() const 
{ 
    return qwtMin(d_x.size(), d_y.size()); 
}

/*!
  Return the x value of data point i

  \param i Index
  \return x X value of data point i
*/
double QwtArrayData::x(size_t i) const 
{ 
    return d_x[int(i)]; 
}

/*!
  Return the y value of data point i

  \param i Index
  \return y Y value of data point i
*/
double QwtArrayData::y(size_t i) const 
{ 
    return d_y[int(i)]; 
}

//! \return Array of the x-values
const QwtArray<double> &QwtArrayData::xData() const
{
    return d_x;
}

//! \return Array of the y-values
const QwtArray<double> &QwtArrayData::yData() const
{
    return d_y;
}

/*!
  \return Pointer to a copy (virtual copy constructor)
*/
QwtData *QwtArrayData::copy() const 
{ 
    return new QwtArrayData(d_x, d_y); 
}

/*!
  Returns the bounding rectangle of the data. If there is
  no bounding rect, like for empty data the rectangle is invalid:
  QwtDoubleRect::isValid() == false
*/
QwtDoubleRect QwtArrayData::boundingRect() const
{
    const size_t sz = size();

    if ( sz <= 0 )
        return QwtDoubleRect(1.0, 1.0, -2.0, -2.0); // invalid

    double minX, maxX, minY, maxY;
    QwtArray<double>::ConstIterator xIt = d_x.begin();
    QwtArray<double>::ConstIterator yIt = d_y.begin();
    QwtArray<double>::ConstIterator end = d_x.begin() + sz;
    minX = maxX = *xIt++;
    minY = maxY = *yIt++;

    while ( xIt < end )
    {
        const double xv = *xIt++;
        if ( xv < minX )
            minX = xv;
        if ( xv > maxX )
            maxX = xv;

        const double yv = *yIt++;
        if ( yv < minY )
            minY = yv;
        if ( yv > maxY )
            maxY = yv;
    }
    return QwtDoubleRect(minX, minY, maxX - minX, maxY - minY);
}

/*!
  Constructor

  \param x Array of x values
  \param y Array of y values
  \param 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.

  \sa QwtPlotCurve::setData(), QwtPlotCurve::setRawData()
*/
QwtCPointerData::QwtCPointerData(
    const double *x, const double *y, size_t size):
    d_x(x), 
    d_y(y), 
    d_size(size)
{
}

//! Assignment 
QwtCPointerData& QwtCPointerData::operator=(const QwtCPointerData &data)
{
    if (this != &data)
    {
        d_x = data.d_x;
        d_y = data.d_y;
        d_size = data.d_size;
    }
    return *this;
}

//! \return Size of the data set 
size_t QwtCPointerData::size() const 
{   
    return d_size; 
}

/*!
  Return the x value of data point i

  \param i Index
  \return x X value of data point i
*/
double QwtCPointerData::x(size_t i) const 
{ 
    return d_x[int(i)]; 
}

/*!
  Return the y value of data point i

  \param i Index
  \return y Y value of data point i
*/
double QwtCPointerData::y(size_t i) const 
{ 
    return d_y[int(i)]; 
}

//! \return Array of the x-values
const double *QwtCPointerData::xData() const
{
    return d_x;
}

//! \return Array of the y-values
const double *QwtCPointerData::yData() const
{
    return d_y;
}

/*!
  \return Pointer to a copy (virtual copy constructor)
*/
QwtData *QwtCPointerData::copy() const 
{
    return new QwtCPointerData(d_x, d_y, d_size);
}

/*!
  Returns the bounding rectangle of the data. If there is
  no bounding rect, like for empty data the rectangle is invalid:
  QwtDoubleRect::isValid() == false
*/
QwtDoubleRect QwtCPointerData::boundingRect() const
{
    const size_t sz = size();

    if ( sz <= 0 )
        return QwtDoubleRect(1.0, 1.0, -2.0, -2.0); // invalid

    double minX, maxX, minY, maxY;
    const double *xIt = d_x;
    const double *yIt = d_y;
    const double *end = d_x + sz;
    minX = maxX = *xIt++;
    minY = maxY = *yIt++;

    while ( xIt < end )
    {
        const double xv = *xIt++;
        if ( xv < minX )
            minX = xv;
        if ( xv > maxX )
            maxX = xv;

        const double yv = *yIt++;
        if ( yv < minY )
            minY = yv;
        if ( yv > maxY )
            maxY = yv;
    }
    return QwtDoubleRect(minX, minY, maxX - minX, maxY - minY);
}