Revision control
++ // Copyright (C) 2016 The Qt Company Ltd.
++ // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
++ // Qt-Security score:significant reason:default
++
++ #ifndef QTCONCURRENT_MEDIAN_H
++ #define QTCONCURRENT_MEDIAN_H
++
++ #include <QtConcurrent/qtconcurrent_global.h>
++
++ #if !defined(QT_NO_CONCURRENT) || defined(Q_QDOC)
++
++ #include <algorithm>
++ #include <cstring>
++
++ QT_BEGIN_NAMESPACE
++
++ namespace QtConcurrent {
++
++ class Median
++ {
++ public:
++ enum { BufferSize = 7 };
++
++ Median()
++ : currentMedian(), currentIndex(0), valid(false), dirty(true)
++ {
++ std::fill_n(values, static_cast<int>(BufferSize), 0.0);
++ }
++
++ void reset()
++ {
++ std::fill_n(values, static_cast<int>(BufferSize), 0.0);
++ currentIndex = 0;
++ valid = false;
++ dirty = true;
++ }
++
++ void addValue(double value)
++ {
++ ++currentIndex;
++ if (currentIndex == BufferSize) {
++ currentIndex = 0;
++ valid = true;
++ }
++
++ // Only update the cached median value when we have to, that
++ // is when the new value is on then other side of the median
++ // compared to the current value at the index.
++ const double currentIndexValue = values[currentIndex];
++ if ((currentIndexValue > currentMedian && currentMedian > value)
++ || (currentMedian > currentIndexValue && value > currentMedian)) {
++ dirty = true;
++ }
++
++ values[currentIndex] = value;
++ }
++
++ bool isMedianValid() const
++ {
++ return valid;
++ }
++
++ double median()
++ {
++ if (dirty) {
++ dirty = false;
++
++ double sorted[BufferSize];
++ ::memcpy(&sorted, &values, sizeof(sorted));
++ std::sort(sorted, sorted + static_cast<int>(BufferSize));
++ currentMedian = sorted[BufferSize / 2];
++ }
++
++ return currentMedian;
++ }
++
++ private:
++ double values[BufferSize];
++ double currentMedian;
++ int currentIndex;
++ bool valid;
++ bool dirty;
++ };
++
++ } // namespace QtConcurrent
++
++ QT_END_NAMESPACE
++
++ #endif // QT_NO_CONCURRENT
++
++ #endif