This file is indexed.

/usr/include/qwt-qt4/qwt_spline.h is in libqwt5-qt4-dev 5.2.2-1ubuntu2.

This file is owned by root:root, with mode 0o644.

The actual contents of the file can be viewed below.

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
/* -*- 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
 *****************************************************************************/

#ifndef QWT_SPLINE_H
#define QWT_SPLINE_H

#include "qwt_global.h"
#include "qwt_double_rect.h"

#if QT_VERSION >= 0x040000
#include <QPolygonF>
#else
#include "qwt_array.h"
#endif

// MOC_SKIP_BEGIN

#if defined(QWT_TEMPLATEDLL)

#if QT_VERSION < 0x040000
#ifndef QWTARRAY_TEMPLATE_QWTDOUBLEPOINT // by mjo3
#define QWTARRAY_TEMPLATE_QWTDOUBLEPOINT
template class QWT_EXPORT QwtArray<QwtDoublePoint>;
#endif //end of QWTARRAY_TEMPLATE_QWTDOUBLEPOINT
#endif

#endif

// MOC_SKIP_END

/*!
  \brief A class for spline interpolation

  The QwtSpline class is used for cubical spline interpolation.
  Two types of splines, natural and periodic, are supported.
  
  \par Usage:
  <ol>
  <li>First call setPoints() to determine the spline coefficients 
      for a tabulated function y(x).
  <li>After the coefficients have been set up, the interpolated
      function value for an argument x can be determined by calling 
      QwtSpline::value().
  </ol>

  \par Example:
  \code
#include <qwt_spline.h>

QPolygonF interpolate(const QPolygonF& points, int numValues)
{
    QwtSpline spline;
    if ( !spline.setPoints(points) ) 
        return points;

    QPolygonF interpolatedPoints(numValues);

    const double delta = 
        (points[numPoints - 1].x() - points[0].x()) / (points.size() - 1);
    for(i = 0; i < points.size(); i++)  / interpolate
    {
        const double x = points[0].x() + i * delta;
        interpolatedPoints[i].setX(x);
        interpolatedPoints[i].setY(spline.value(x));
    }
    return interpolatedPoints;
}
  \endcode
*/

class QWT_EXPORT QwtSpline
{
public:
    //! Spline type
    enum SplineType
    {
        Natural,
        Periodic
    };

    QwtSpline();
    QwtSpline( const QwtSpline & );

    ~QwtSpline();

    QwtSpline &operator=( const QwtSpline & );

    void setSplineType(SplineType);
    SplineType splineType() const;

#if QT_VERSION < 0x040000
    bool setPoints(const QwtArray<QwtDoublePoint>& points);
    QwtArray<QwtDoublePoint> points() const;
#else
    bool setPoints(const QPolygonF& points);
    QPolygonF points() const;
#endif

    void reset();

    bool isValid() const;
    double value(double x) const;

    const QwtArray<double> &coefficientsA() const;
    const QwtArray<double> &coefficientsB() const;
    const QwtArray<double> &coefficientsC() const;

protected:

#if QT_VERSION < 0x040000
    bool buildNaturalSpline(
        const QwtArray<QwtDoublePoint> &);
    bool buildPeriodicSpline(
        const QwtArray<QwtDoublePoint> &);
#else
    bool buildNaturalSpline(const QPolygonF &);
    bool buildPeriodicSpline(const QPolygonF &);
#endif

    class PrivateData;
    PrivateData *d_data;
};

#endif