MDBox.hxx

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// Mantid Repository : https://github.com/mantidproject/mantid
//
// Copyright © 2018 ISIS Rutherford Appleton Laboratory UKRI,
//   NScD Oak Ridge National Laboratory, European Spallation Source,
//   Institut Laue - Langevin & CSNS, Institute of High Energy Physics, CAS
// SPDX - License - Identifier: GPL - 3.0 +
#include "MantidDataObjects/MDBox.h"
#include "MantidDataObjects/MDBoxSaveable.h"
#include "MantidDataObjects/MDEvent.h"
#include "MantidDataObjects/MDGridBox.h"
#include "MantidDataObjects/MDLeanEvent.h"
#include "MantidKernel/DiskBuffer.h"
#include <algorithm>
#include <boost/math/special_functions/round.hpp>
#include <cmath>
#include <numeric>
 
namespace Mantid {
namespace DataObjects {
 
TMDE(MDBox)::~MDBox() {
  if (m_Saveable) {
    // tell disk buffer that there are no point of tracking this box any more.
    // BAD!!! TODO: make correct destructors order.
    if (this->m_BoxController) // it is destructor, in tests everything may fall
                               // apart, though it should not be issue for a
                               // workspace
    {
      if (this->m_BoxController->isFileBacked()) {
        this->m_BoxController->getFileIO()->objectDeleted(m_Saveable.get());
      }
    }
  }
}
//-----------------------------------------------------------------------------------------------
TMDE(MDBox)::MDBox(API::BoxController_sptr &splitter, const uint32_t depth, const size_t nBoxEvents, const size_t boxID)
    : MDBoxBase<MDE, nd>(splitter.get(), depth, boxID), m_Saveable(nullptr), m_bIsMasked(false) {
  initMDBox(nBoxEvents);
}
 
//-----------------------------------------------------------------------------------------------
TMDE(MDBox)::MDBox(API::BoxController *const splitter, const uint32_t depth, const size_t nBoxEvents,
                   const size_t boxID)
    : MDBoxBase<MDE, nd>(splitter, depth, boxID), m_Saveable(nullptr), m_bIsMasked(false) {
  initMDBox(nBoxEvents);
}
 
//-----------------------------------------------------------------------------------------------
TMDE(MDBox)::MDBox(API::BoxController_sptr &splitter, const uint32_t depth,
                   const std::vector<Mantid::Geometry::MDDimensionExtents<coord_t>> &extentsVector,
                   const size_t nBoxEvents, const size_t boxID)
    : MDBoxBase<MDE, nd>(splitter.get(), depth, boxID, extentsVector), m_Saveable(nullptr), m_bIsMasked(false) {
  initMDBox(nBoxEvents);
}
//-----------------------------------------------------------------------------------------------
TMDE(MDBox)::MDBox(API::BoxController *const splitter, const uint32_t depth,
                   const std::vector<Mantid::Geometry::MDDimensionExtents<coord_t>> &extentsVector,
                   const size_t nBoxEvents, const size_t boxID)
    : MDBoxBase<MDE, nd>(splitter, depth, boxID, extentsVector), m_Saveable(nullptr), m_bIsMasked(false) {
  initMDBox(nBoxEvents);
}
 
template <typename MDE, size_t nd>
MDBox<MDE, nd>::MDBox(Mantid::API::BoxController *const bc, const uint32_t depth,
                      const std::vector<Mantid::Geometry::MDDimensionExtents<coord_t>> &extentsVector,
                      EventIterator begin, EventIterator end)
    : MDBoxBase<MDE, nd>(bc, depth, 0, extentsVector), m_Saveable(nullptr), data(std::vector<MDE>(begin, end)),
      m_bIsMasked(false) {
  MDBoxBase<MDE, nd>::calcCaches(data.begin(), data.end());
  if (this->m_BoxController->isFileBacked())
    this->setFileBacked();
}
 
TMDE(void MDBox)::initMDBox(const size_t nBoxEvents) {
  if (this->m_BoxController->getNDims() != nd)
    throw std::invalid_argument("MDBox::ctor(): controller passed has the wrong number of dimensions.");
 
  if (nBoxEvents != UNDEF_SIZET)
    data.reserve(nBoxEvents);
 
  if (this->m_BoxController->isFileBacked())
    this->setFileBacked();
}
 
//-----------------------------------------------------------------------------------------------
TMDE(MDBox)::MDBox(const MDBox<MDE, nd> &other, Mantid::API::BoxController *const otherBC)
    : MDBoxBase<MDE, nd>(other, otherBC), m_Saveable(nullptr), data(other.data), m_bIsMasked(other.m_bIsMasked) {
  if (otherBC) // may be absent in some tests but generally have to be present
  {
    if (otherBC->isFileBacked())
      this->setFileBacked();
  }
}
// unhide MDBoxBase method
TMDE(size_t MDBox)::addEventsUnsafe(const std::vector<MDE> &events) {
  return MDBoxBase<MDE, nd>::addEventsUnsafe(events);
}
 
//-----------------------------------------------------------------------------------------------
TMDE(void MDBox)::clear() {
  // Make sure the object is not in any of the disk MRUs, and mark any space it
  // used as free
  // if (this->m_BoxController->useWriteBuffer())
  if (m_Saveable)
    this->m_BoxController->getFileIO()->objectDeleted(m_Saveable.get());
 
  // Clear all contents
  this->m_signal = 0.0;
  this->m_errorSquared = 0.0;
 
  this->clearDataFromMemory();
}
 
TMDE(Kernel::ISaveable *MDBox)::getISaveable() { return m_Saveable.get(); }
TMDE(Kernel::ISaveable *MDBox)::getISaveable() const { return m_Saveable.get(); }
 
//-----------------------------------------------------------------------------------------------
TMDE(void MDBox)::clearDataFromMemory() {
  data.clear();
  vec_t().swap(data); // Linux trick to really free the memory
  // mark data unchanged
  if (m_Saveable) {
    m_Saveable->setLoaded(false);
    m_Saveable->setBusy(false);
    m_Saveable->clearDataChanged();
  }
}
 
//-----------------------------------------------------------------------------------------------
TMDE(size_t MDBox)::getNumDims() const { return nd; }
 
//-----------------------------------------------------------------------------------------------
TMDE(size_t MDBox)::getNumMDBoxes() const { return 1; }
 
//-----------------------------------------------------------------------------------------------
TMDE(void MDBox)::getBoxes(std::vector<MDBoxBase<MDE, nd> *> &boxes, size_t /*maxDepth*/, bool /*leafOnly*/) {
  boxes.emplace_back(this);
}
TMDE(void MDBox)::getBoxes(std::vector<API::IMDNode *> &boxes, size_t /*maxDepth*/, bool /*leafOnly*/) {
  boxes.emplace_back(this);
}
 
//-----------------------------------------------------------------------------------------------
TMDE(void MDBox)::getBoxes(std::vector<MDBoxBase<MDE, nd> *> &boxes, size_t /*maxDepth*/, bool /*leafOnly*/,
                           Mantid::Geometry::MDImplicitFunction * /*function*/) {
  boxes.emplace_back(this);
}
TMDE(void MDBox)::getBoxes(std::vector<API::IMDNode *> &boxes, size_t /*maxDepth*/, bool /*leafOnly*/,
                           Mantid::Geometry::MDImplicitFunction * /*function*/) {
  boxes.emplace_back(this);
}
 
//-----------------------------------------------------------------------------------------------
TMDE(uint64_t MDBox)::getNPoints() const {
  if (!m_Saveable)
    return data.size();
 
  if (m_Saveable->wasSaved()) {
    if (m_Saveable->isLoaded())
      return data.size();
    else // m_fileNumEvents
      return m_Saveable->getFileSize() + data.size();
  } else
    return data.size();
}
 
//-----------------------------------------------------------------------------------------------
TMDE(std::vector<MDE> &MDBox)::getEvents() {
  if (!m_Saveable)
    return data;
  else {
    if (m_Saveable->wasSaved()) { // Load and concatenate the events if needed
      m_Saveable->load();         // this will set isLoaded to true if not already loaded;
    }
    // The data vector is busy - can't release the memory yet
    m_Saveable->setBusy(true);
    // the non-const access to events assumes that the data will be modified;
    m_Saveable->setDataChanged();
 
    // Tell the to-write buffer to discard the object (when no longer busy) as
    // it has not been modified
    this->m_BoxController->getFileIO()->toWrite(m_Saveable.get());
    // else: do nothing if the events are already in memory.
    return data;
  }
}
 
TMDE(const std::vector<MDE> &MDBox)::getEvents() const { return getConstEvents(); }
//-----------------------------------------------------------------------------------------------
TMDE(const std::vector<MDE> &MDBox)::getConstEvents() const {
  if (!m_Saveable)
    return data;
  else {
    if (m_Saveable->wasSaved()) {
      // Load and concatenate the events if needed
      m_Saveable->load(); // this will set isLoaded to true if not already loaded;
      // This access to data was const. Don't change the m_dataModified flag.
    }
    // The data vector is busy - can't release the memory yet
    m_Saveable->setBusy(true);
 
    // Tell the to-write buffer to discard the object (when no longer busy) as
    // it has not been modified
    this->m_BoxController->getFileIO()->toWrite(m_Saveable.get());
    // else: do nothing if the events are already in memory.
    return data;
  }
}
 
//-----------------------------------------------------------------------------------------------
TMDE(void MDBox)::releaseEvents() {
  // Data vector is no longer busy.
  if (m_Saveable)
    m_Saveable->setBusy(false);
}
 
TMDE(void MDBox)::getEventsData(std::vector<coord_t> &coordTable, size_t &nColumns) const {
  double signal, errorSq;
  MDE::eventsToData(this->data, coordTable, nColumns, signal, errorSq);
  this->m_signal = static_cast<signal_t>(signal);
  this->m_errorSquared = static_cast<signal_t>(errorSq);
 
#ifdef MDBOX_TRACK_CENTROID
  this->calculateCentroid(this->m_centroid);
#endif
}
TMDE(void MDBox)::setEventsData(const std::vector<coord_t> &coordTable) { MDE::dataToEvents(coordTable, this->data); }
 
//-----------------------------------------------------------------------------------------------
TMDE(std::vector<MDE> *MDBox)::getEventsCopy() {
  if (m_Saveable) {
  }
  auto out = new std::vector<MDE>();
  // Make the copy
  out->insert(out->begin(), data.begin(), data.end());
  return out;
}
 
//-----------------------------------------------------------------------------------------------
TMDE(void MDBox)::refreshCache(Kernel::ThreadScheduler * /*ts*/) {
 
  // Use the cached value if it is on disk
 
  // Convert floats to doubles to preserve precision when adding them.
  double signalSum{0};
  double errorSum{0};
 
  if (m_Saveable) {
    if (m_Saveable->wasSaved()) // There are possible problems with disk
                                // buffered events, as saving calculates
                                // averages and these averages has to be added
                                // to memory contents
    {
      if (!m_Saveable->isLoaded()) // events were saved,  averages calculated
                                   // and stored
      {
        // the partial data were not loaded from HDD but their averages should
        // be calculated when loaded. Add them
        signalSum = this->m_signal;
        errorSum = this->m_errorSquared;
      }
    }
  }
 
  // calculate all averages from memory
  signalSum = std::accumulate(data.cbegin(), data.cend(), signalSum,
                              [](const double &sum, const MDE &event) { return sum + event.getSignal(); });
  errorSum = std::accumulate(data.cbegin(), data.cend(), errorSum,
                             [](const double &sum, const MDE &event) { return sum + event.getErrorSquared(); });
 
  this->m_signal = signal_t(signalSum);
  this->m_errorSquared = signal_t(errorSum);
#ifdef MDBOX_TRACK_CENTROID
  this->calculateCentroid(this->m_centroid);
#endif
 
  this->m_totalWeight = static_cast<double>(this->getNPoints());
}
 
TMDE(bool MDBox)::isDataAdded() const {
  if (m_Saveable) {
    if (m_Saveable->isLoaded())
      return data.size() != m_Saveable->getFileSize();
  }
  return (!data.empty());
}
 
//-----------------------------------------------------------------------------------------------
TMDE(void MDBox)::calculateCentroid(coord_t *centroid) const {
  std::fill_n(centroid, nd, 0.0f);
 
  // Signal was calculated before (when adding)
  // Keep 0.0 if the signal is null. This avoids dividing by 0.0
  if (this->m_signal == 0)
    return;
 
  for (const MDE &Evnt : data) {
    double signal = Evnt.getSignal();
    for (size_t d = 0; d < nd; d++) {
      // Total up the coordinate weighted by the signal.
      centroid[d] += Evnt.getCenter(d) * static_cast<coord_t>(signal);
    }
  }
 
  // Normalize by the total signal
  const coord_t reciprocal = 1.0f / static_cast<coord_t>(this->m_signal);
  for (size_t d = 0; d < nd; ++d) {
    centroid[d] *= reciprocal;
  }
}
 
//-----------------------------------------------------------------------------------------------
TMDE(void MDBox)::calculateCentroid(coord_t *centroid, const int expInfoIndex) const {
 
  std::fill_n(centroid, nd, 0.0f);
 
  // Signal was calculated before (when adding)
  // Keep 0.0 if the signal is null. This avoids dividing by 0.0
  if (this->m_signal == 0)
    return;
 
  for (const MDE &Evnt : data) {
    coord_t signal = Evnt.getSignal();
    if (Evnt.getExpInfoIndex() == expInfoIndex) {
      for (size_t d = 0; d < nd; d++) {
        // Total up the coordinate weighted by the signal.
        centroid[d] += Evnt.getCenter(d) * signal;
      }
    }
  }
 
  // Normalize by the total signal
  const coord_t reciprocal = 1.0f / static_cast<coord_t>(this->m_signal);
  for (size_t d = 0; d < nd; ++d) {
    centroid[d] *= reciprocal;
  }
}
 
//-----------------------------------------------------------------------------------------------
TMDE(void MDBox)::calculateDimensionStats(MDDimensionStats *stats) const {
  for (const MDE &Evnt : data) {
    for (size_t d = 0; d < nd; d++) {
      stats[d].addPoint(Evnt.getCenter(d));
    }
  }
}
 
TMDE(void MDBox)::integrateSphere(Mantid::API::CoordTransform &radiusTransform, const coord_t radiusSquared,
                                  signal_t &integratedSignal, signal_t &errorSquared, const coord_t innerRadiusSquared,
                                  const bool useOnePercentBackgroundCorrection) const {
  // If the box is cached to disk, you need to retrieve it
  const std::vector<MDE> &events = this->getConstEvents();
  if (innerRadiusSquared == 0.0) {
    // For each MDLeanEvent
    for (const auto &it : events) {
      coord_t out[nd];
      radiusTransform.apply(it.getCenter(), out);
      if (out[0] < radiusSquared) {
        integratedSignal += static_cast<signal_t>(it.getSignal());
        errorSquared += static_cast<signal_t>(it.getErrorSquared());
      }
    }
  } else {
    // For each MDLeanEvent
    using valAndErrorPair = std::pair<signal_t, signal_t>;
    std::vector<valAndErrorPair> vals;
    for (const auto &it : events) {
      coord_t out[nd];
      radiusTransform.apply(it.getCenter(), out);
      if (out[0] < radiusSquared && out[0] > innerRadiusSquared) {
        const auto signal = static_cast<signal_t>(it.getSignal());
        const auto errSquared = static_cast<signal_t>(it.getErrorSquared());
        vals.emplace_back(signal, errSquared);
      }
    }
    // Sort based on signal values
    std::sort(vals.begin(), vals.end(),
              [](const valAndErrorPair &a, const valAndErrorPair &b) { return a.first < b.first; });
 
    // Remove top 1% of background
    const size_t endIndex =
        useOnePercentBackgroundCorrection ? static_cast<size_t>(0.99 * static_cast<double>(vals.size())) : vals.size();
 
    for (size_t k = 0; k < endIndex; k++) {
      integratedSignal += vals[k].first;
      errorSquared += vals[k].second;
    }
  }
  // it is constant access, so no saving or fiddling with the buffer is needed.
  // Events just can be dropped if necessary
  // m_Saveable->releaseEvents();
  if (m_Saveable) {
    m_Saveable->setBusy(false);
  }
}
 
TMDE(void MDBox)::integrateCylinder(Mantid::API::CoordTransform &radiusTransform, const coord_t radius,
                                    const coord_t length, signal_t &signal, signal_t &errorSquared,
                                    std::vector<signal_t> &signal_fit) const {
  // If the box is cached to disk, you need to retrieve it
  const std::vector<MDE> &events = this->getConstEvents();
  size_t numSteps = signal_fit.size();
  double deltaQ = length / static_cast<double>(numSteps - 1);
 
  // For each MDLeanEvent
  for (const auto &evnt : events) {
    coord_t out[2]; // radius and length of cylinder
    radiusTransform.apply(evnt.getCenter(), out);
    if (out[0] < radius && std::fabs(out[1]) < 0.5 * length + deltaQ) {
      // add event to appropriate y channel
      size_t xchannel = static_cast<size_t>(std::floor(out[1] / deltaQ)) + numSteps / 2;
      if (xchannel < numSteps)
        signal_fit[xchannel] += static_cast<signal_t>(evnt.getSignal());
 
      signal += static_cast<signal_t>(evnt.getSignal());
      errorSquared += static_cast<signal_t>(evnt.getErrorSquared());
    }
  }
  // it is constant access, so no saving or fiddling with the buffer is needed.
  // Events just can be dropped if necessary
  // m_Saveable->releaseEvents();
  if (m_Saveable) {
    m_Saveable->setBusy(false);
  }
}
 
//-----------------------------------------------------------------------------------------------
TMDE(coord_t *MDBox)::getCentroid() const { return this->m_centroid; }
 
//-----------------------------------------------------------------------------------------------
TMDE(void MDBox)::centroidSphere(Mantid::API::CoordTransform &radiusTransform, const coord_t radiusSquared,
                                 coord_t *centroid, signal_t &signal) const {
  // If the box is cached to disk, you need to retrieve it
  const std::vector<MDE> &events = this->getConstEvents();
 
  // For each MDLeanEvent
  for (const auto &evnt : events) {
    coord_t out[nd];
    radiusTransform.apply(evnt.getCenter(), out);
    if (out[0] < radiusSquared) {
      coord_t eventSignal = static_cast<coord_t>(evnt.getSignal());
      signal += eventSignal;
      for (size_t d = 0; d < nd; d++)
        centroid[d] += evnt.getCenter(d) * eventSignal;
    }
  }
  // it is constant access, so no saving or fiddling with the buffer is needed.
  // Events just can be dropped if necessary
  if (m_Saveable)
    m_Saveable->setBusy(false);
}
 
//-----------------------------------------------------------------------------------------------
TMDE(void MDBox)::transformDimensions(std::vector<double> &scaling, std::vector<double> &offset) {
  MDBoxBase<MDE, nd>::transformDimensions(scaling, offset);
  this->calculateCentroid(this->m_centroid);
  std::vector<MDE> &events = this->getEvents();
  for (auto &evnt : events) {
    coord_t *center = evnt.getCenterNonConst();
    for (size_t d = 0; d < nd; d++)
      center[d] = (center[d] * static_cast<coord_t>(scaling[d])) + static_cast<coord_t>(offset[d]);
  }
  if (m_Saveable)
    m_Saveable->setBusy(false);
}
 
TMDE(void MDBox)::mask() {
  this->setSignal(API::MDMaskValue);
  this->setErrorSquared(API::MDMaskValue);
  m_bIsMasked = true;
}
 
TMDE(void MDBox)::unmask() { m_bIsMasked = false; }
//------------------------------------------------------------------------------------------------------------------------------------------------------------
 
TMDE(size_t MDBox)::buildAndAddEvents(const std::vector<signal_t> &sigErrSq, const std::vector<coord_t> &Coord,
                                      const std::vector<uint16_t> &expInfoIndex,
                                      const std::vector<uint16_t> &goniometerIndex,
                                      const std::vector<uint32_t> &detectorId) {
 
  size_t nEvents = sigErrSq.size() / 2;
  size_t nExisiting = data.size();
  data.reserve(nExisiting + nEvents);
  std::lock_guard<std::mutex> _lock(this->m_dataMutex);
  IF<MDE, nd>::EXEC(this->data, sigErrSq, Coord, expInfoIndex, goniometerIndex, detectorId, nEvents);
 
  return 0;
}
 
TMDE(void MDBox)::buildAndAddEvent(const signal_t Signal, const signal_t errorSq, const std::vector<coord_t> &point,
                                   uint16_t expInfoIndex, uint16_t goniometerIndex, uint32_t detectorId) {
  std::lock_guard<std::mutex> _lock(this->m_dataMutex);
  this->data.emplace_back(
      IF<MDE, nd>::BUILD_EVENT(Signal, errorSq, &point[0], expInfoIndex, goniometerIndex, detectorId));
}
 
//-----------------------------------------------------------------------------------------------
TMDE(void MDBox)::buildAndAddEventUnsafe(const signal_t Signal, const signal_t errorSq,
                                         const std::vector<coord_t> &point, uint16_t expInfoIndex,
                                         uint16_t goniometerIndex, uint32_t detectorId) {
  this->data.emplace_back(
      IF<MDE, nd>::BUILD_EVENT(Signal, errorSq, &point[0], expInfoIndex, goniometerIndex, detectorId));
}
 
//-----------------------------------------------------------------------------------------------
TMDE(size_t MDBox)::addEvent(const MDE &Evnt) {
  std::lock_guard<std::mutex> _lock(this->m_dataMutex);
  this->data.emplace_back(Evnt);
  return 1;
}
 
//-----------------------------------------------------------------------------------------------
TMDE(size_t MDBox)::addEventUnsafe(const MDE &Evnt) {
  this->data.emplace_back(Evnt);
  return 1;
}
 
//-----------------------------------------------------------------------------------------------
TMDE(size_t MDBox)::addEvents(const std::vector<MDE> &events) {
  std::lock_guard<std::mutex> _lock(this->m_dataMutex);
  // Copy all the events
  this->data.insert(this->data.end(), events.cbegin(), events.cend());
  return 0;
}
 
TMDE(void MDBox)::setFileBacked(const uint64_t fileLocation, const size_t fileSize, const bool markSaved) {
  if (!m_Saveable)
    m_Saveable = std::make_unique<MDBoxSaveable>(this);
 
  m_Saveable->setFilePosition(fileLocation, fileSize, markSaved);
}
TMDE(void MDBox)::setFileBacked() {
  if (!m_Saveable)
    this->setFileBacked(UNDEF_UINT64, this->getDataInMemorySize(), false);
}
 
TMDE(void MDBox)::saveAt(API::IBoxControllerIO *const FileSaver, uint64_t position) const {
  if (data.empty())
    return;
 
  if (!FileSaver)
    throw(std::invalid_argument(" Needs defined file saver to save data to it"));
  if (!FileSaver->isOpened())
    throw(std::invalid_argument(" The data file has to be opened to use box SaveAt function"));
 
  std::vector<coord_t> TabledData;
  size_t nDataColumns;
  double totalSignal, totalErrSq;
 
  MDE::eventsToData(this->data, TabledData, nDataColumns, totalSignal, totalErrSq);
 
  this->m_signal = static_cast<signal_t>(totalSignal);
  this->m_errorSquared = static_cast<signal_t>(totalErrSq);
#ifdef MDBOX_TRACK_CENTROID
  this->calculateCentroid(this->m_centroid);
#endif
 
  FileSaver->saveBlock(TabledData, position);
}
 
TMDE(void MDBox)::reserveMemoryForLoad(uint64_t size) { this->data.reserve(size); }
 
TMDE(void MDBox)::loadAndAddFrom(API::IBoxControllerIO *const FileSaver, uint64_t filePosition, size_t nEvents,
                                 std::vector<coord_t> &tableDataTemp) {
  if (nEvents == 0)
    return;
 
  if (!FileSaver)
    throw(std::invalid_argument(" Needs defined file saver to load data using it"));
  if (!FileSaver->isOpened())
    throw(std::invalid_argument(" The data file has to be opened to use box loadAndAddFrom function"));
 
  std::lock_guard<std::mutex> _lock(this->m_dataMutex);
 
  tableDataTemp.clear();
  FileSaver->loadBlock(tableDataTemp, filePosition, nEvents);
 
  // convert data to events appending new events to existing
  MDE::dataToEvents(tableDataTemp, data, false);
}
 
TMDE(void MDBox)::loadAndAddFrom(API::IBoxControllerIO *const FileSaver, uint64_t filePosition, size_t nEvents) {
  if (nEvents == 0)
    return;
 
  if (!FileSaver)
    throw(std::invalid_argument(" Needs defined file saver to load data using it"));
  if (!FileSaver->isOpened())
    throw(std::invalid_argument(" The data file has to be opened to use box loadAndAddFrom function"));
 
  std::lock_guard<std::mutex> _lock(this->m_dataMutex);
 
  m_tableData.clear();
  FileSaver->loadBlock(m_tableData, filePosition, nEvents);
 
  // convert data to events appending new events to existing
  MDE::dataToEvents(m_tableData, data, false);
}
TMDE(void MDBox)::clearFileBacked(bool loadDiskBackedData) {
  if (m_Saveable) {
    if (loadDiskBackedData)
      m_Saveable->load();
    // tell disk buffer that there are no point of tracking this box any more.
    this->m_BoxController->getFileIO()->objectDeleted(m_Saveable.get());
    m_Saveable = nullptr;
  }
}
 
} // namespace DataObjects
 
} // namespace Mantid