C++ File::getAttr方法代码示例

/** Load the pulse times, if needed. This sets
 * thisBankPulseTimes to the right pointer.
 * */
void LoadBankFromDiskTask::loadPulseTimes(::NeXus::File &file) {
  try {
    // First, get info about the event_time_zero field in this bank
    file.openData("event_time_zero");
  } catch (::NeXus::Exception &) {
    // Field not found error is most likely.
    // Use the "proton_charge" das logs.
    thisBankPulseTimes = m_loader.alg->m_allBanksPulseTimes;
    return;
  }
  std::string thisStartTime;
  size_t thisNumPulses = 0;
  file.getAttr("offset", thisStartTime);
  if (!file.getInfo().dims.empty())
    thisNumPulses = file.getInfo().dims[0];
  file.closeData();

  // Now, we look through existing ones to see if it is already loaded
  // thisBankPulseTimes = NULL;
  for (auto &bankPulseTime : m_loader.m_bankPulseTimes) {
    if (bankPulseTime->equals(thisNumPulses, thisStartTime)) {
      thisBankPulseTimes = bankPulseTime;
      return;
    }
  }

  // Not found? Need to load and add it
  thisBankPulseTimes = boost::make_shared<BankPulseTimes>(boost::ref(file),
                                                          m_framePeriodNumbers);
  m_loader.m_bankPulseTimes.push_back(thisBankPulseTimes);
}

/** Try to load the "Veto_pulse" field in DASLogs
 * and convert it to a sample log.
 *
 * @param file :: open nexus file at the DASLogs group
 * @param workspace :: workspace to add to.
 */
void LoadNexusLogs::loadVetoPulses(
    ::NeXus::File &file,
    boost::shared_ptr<API::MatrixWorkspace> workspace) const {
  try {
    file.openGroup("Veto_pulse", "NXgroup");
  } catch (::NeXus::Exception &) {
    // No group. This is common in older files
    return;
  }
  file.openData("veto_pulse_time");

  // Load the start date/time as ISO8601 string.
  std::string start_time;
  file.getAttr("start_time", start_time);
  DateAndTime start(start_time);

  // Read the offsets
  std::vector<double> time_double;
  file.getData(time_double);

  // Fake values with zeroes.
  std::vector<double> values(time_double.size(), 0.0);
  TimeSeriesProperty<double> *tsp =
      new TimeSeriesProperty<double>("veto_pulse_time");
  tsp->create(start, time_double, values);
  tsp->setUnits("");

  // Add the log
  workspace->mutableRun().addProperty(tsp);

  file.closeData();
  file.closeGroup();
}

/** Open and load the times-of-flight data
*/
void LoadBankFromDiskTask::loadTof(::NeXus::File &file) {
  // Allocate the array
  auto temp = new float[m_loadSize[0]];
  delete[] m_event_time_of_flight;
  m_event_time_of_flight = temp;

  // Get the list of event_time_of_flight's
  if (!m_oldNexusFileNames)
    file.openData("event_time_offset");
  else
    file.openData("event_time_of_flight");

  // Check that the required space is there in the file.
  ::NeXus::Info tof_info = file.getInfo();
  int64_t tof_dim0 = recalculateDataSize(tof_info.dims[0]);
  if (tof_dim0 < m_loadSize[0] + m_loadStart[0]) {
    m_loader.alg->getLogger().warning()
        << "Entry " << entry_name << "'s event_time_offset field is too small "
                                     "to load the desired data.\n";
    m_loadError = true;
  }

  // Check that the type is what it is supposed to be
  if (tof_info.type == ::NeXus::FLOAT32)
    file.getSlab(m_event_time_of_flight, m_loadStart, m_loadSize);
  else {
    m_loader.alg->getLogger().warning()
        << "Entry " << entry_name
        << "'s event_time_offset field is not FLOAT32! It will be skipped.\n";
    m_loadError = true;
  }

  if (!m_loadError) {
    std::string units;
    file.getAttr("units", units);
    if (units != "microsecond") {
      m_loader.alg->getLogger().warning()
          << "Entry " << entry_name << "'s event_time_offset field's units are "
                                       "not microsecond. It will be skipped.\n";
      m_loadError = true;
    }
    file.closeData();
  } // no error
}

/** Open and load the times-of-flight data
 * @param file An NeXus::File object opened at the correct group
 * @returns A new array containing the time of flights for this bank
 */
std::unique_ptr<float[]> LoadBankFromDiskTask::loadTof(::NeXus::File &file) {
  // Allocate the array
  auto event_time_of_flight =
      Mantid::Kernel::make_unique<float[]>(m_loadSize[0]);

  // Get the list of event_time_of_flight's
  std::string key, tof_unit;
  if (!m_oldNexusFileNames)
    key = "event_time_offset";
  else
    key = "event_time_of_flight";
  file.openData(key);

  // Check that the required space is there in the file.
  ::NeXus::Info tof_info = file.getInfo();
  int64_t tof_dim0 = recalculateDataSize(tof_info.dims[0]);
  if (tof_dim0 < m_loadSize[0] + m_loadStart[0]) {
    m_loader.alg->getLogger().warning()
        << "Entry " << entry_name
        << "'s event_time_offset field is too small "
           "to load the desired data.\n";
    m_loadError = true;
  }

  // The Nexus standard does not specify if event_time_offset should be float or
  // integer, so we use the NeXusIOHelper to perform the conversion to float on
  // the fly. If the data field already contains floats, the conversion is
  // skipped.
  auto vec = NeXus::NeXusIOHelper::readNexusSlab<float>(file, key, m_loadStart,
                                                        m_loadSize);
  file.getAttr("units", tof_unit);
  file.closeData();
  // Convert Tof to microseconds
  Kernel::Units::timeConversionVector(vec, tof_unit, "microseconds");
  std::copy(vec.begin(), vec.end(), event_time_of_flight.get());

  return event_time_of_flight;
}

/** Loads an entry from a previously-open NXS file as a log entry
 * in the workspace's run.
 *
 * @param file: NXS file handle. MUST BE PASSED BY REFERENCE otherwise there
 *    occurs a segfault.
 * @param entry_name, entry_class: name and class of NXlog to open.
 */
void LoadLogsFromSNSNexus::loadSampleLog(::NeXus::File& file, std::string entry_name, std::string entry_class)
{
  // whether or not to overwrite logs on workspace
  bool overwritelogs = this->getProperty("OverwriteLogs");

  file.openGroup(entry_name, entry_class);

  // Validate the NX log class.
  map<string, string> entries = file.getEntries();
  if ((entries.find("value") == entries.end()) ||
      (entries.find("time") == entries.end()) )
  {
    g_log.warning() << "Invalid NXlog entry " << entry_name << " found. Did not contain 'value' and 'time'.\n";
    file.closeGroup();
    return;
  }


  ::NeXus::Info info;
  //Two possible types of properties:
  vector<double> values;
  vector<int> values_int;

  bool isTimeSeries = false;
  bool isInt = false;

  file.openData("value");

  //Get the units of the property
  std::string units("");
  try
  {
    file.getAttr("units", units);
  }
  catch (::NeXus::Exception &)
  {
    //Ignore missing units field.
    units = "";
  }

  //If there is more than one entry, it is a timeseries
  info = file.getInfo();
  //isTimeSeries = (info.dims[0] > 1);
  isTimeSeries = true;

  Timer timer1;
  try
  {
    //Get the data (convert types if necessary)
    if (file.isDataInt())
    {
      isInt = true;
      file.getDataCoerce(values_int);
//      if (values_int.size() == 1)
//      {
//        WS->mutableRun().addProperty(entry_name, values_int[0], units);
//      }

    }
    else
    {
      //Try to get as doubles.
      file.getDataCoerce(values);
//      if (values.size() == 1)
//      {
//        WS->mutableRun().addProperty(entry_name, values[0], units);
//      }
    }
  }
  catch (::NeXus::Exception &e)
  {
    g_log.warning() << "NXlog entry " << entry_name << " gave an error when loading 'value' data:'" << e.what() << "'.\n";
    file.closeData();
    file.closeGroup();
    return;
  }
  if (VERBOSE) std::cout << "getDataCoerce took " << timer1.elapsed() << " sec.\n";


  file.closeData();

  if (isTimeSeries)
  {
    // --- Time series property ---

    //Get the times
    vector<double> time_double;
    vector<DateAndTime> times;

    try {
      file.openData("time");
    }
    catch (::NeXus::Exception &e)
//.........这里部分代码省略.........

/**
 * Read histogram data
 * @param histogramEntries map of the file entries that have histogram
 * @param outputGroup pointer to the workspace group
 * @param nxFile Reads data from inside first first top entry
 */
void LoadMcStas::readHistogramData(
    const std::map<std::string, std::string> &histogramEntries,
    WorkspaceGroup_sptr &outputGroup, ::NeXus::File &nxFile) {

  std::string nameAttrValueYLABEL;

  for (const auto &histogramEntry : histogramEntries) {
    const std::string &dataName = histogramEntry.first;
    const std::string &dataType = histogramEntry.second;

    // open second level entry
    nxFile.openGroup(dataName, dataType);

    // grap title to use to e.g. create workspace name
    std::string nameAttrValueTITLE;
    nxFile.getAttr("filename", nameAttrValueTITLE);

    if (nxFile.hasAttr("ylabel")) {
      nxFile.getAttr("ylabel", nameAttrValueYLABEL);
    }

    // Find the axis names
    auto nxdataEntries = nxFile.getEntries();
    std::string axis1Name, axis2Name;
    for (auto &nxdataEntry : nxdataEntries) {
      if (nxdataEntry.second == "NXparameters")
        continue;
      if (nxdataEntry.first == "ncount")
        continue;
      nxFile.openData(nxdataEntry.first);

      if (nxFile.hasAttr("axis")) {
        int axisNo(0);
        nxFile.getAttr("axis", axisNo);
        if (axisNo == 1)
          axis1Name = nxdataEntry.first;
        else if (axisNo == 2)
          axis2Name = nxdataEntry.first;
        else
          throw std::invalid_argument("Unknown axis number");
      }
      nxFile.closeData();
    }

    std::vector<double> axis1Values, axis2Values;
    nxFile.readData<double>(axis1Name, axis1Values);
    if (axis2Name.length() == 0) {
      axis2Name = nameAttrValueYLABEL;
      axis2Values.push_back(0.0);
    } else {
      nxFile.readData<double>(axis2Name, axis2Values);
    }

    const size_t axis1Length = axis1Values.size();
    const size_t axis2Length = axis2Values.size();
    g_log.debug() << "Axis lengths=" << axis1Length << " " << axis2Length
                  << '\n';

    // Require "data" field
    std::vector<double> data;
    nxFile.readData<double>("data", data);

    // Optional errors field
    std::vector<double> errors;
    try {
      nxFile.readData<double>("errors", errors);
    } catch (::NeXus::Exception &) {
      g_log.information() << "Field " << dataName
                          << " contains no error information.\n";
    }

    // close second level entry
    nxFile.closeGroup();

    MatrixWorkspace_sptr ws = WorkspaceFactory::Instance().create(
        "Workspace2D", axis2Length, axis1Length, axis1Length);
    Axis *axis1 = ws->getAxis(0);
    axis1->title() = axis1Name;
    // Set caption
    auto lblUnit = boost::make_shared<Units::Label>();
    lblUnit->setLabel(axis1Name, "");
    axis1->unit() = lblUnit;

    Axis *axis2 = new NumericAxis(axis2Length);
    axis2->title() = axis2Name;
    // Set caption
    lblUnit = boost::make_shared<Units::Label>();
    lblUnit->setLabel(axis2Name, "");
    axis2->unit() = lblUnit;

    ws->setYUnit(axis2Name);
    ws->replaceAxis(1, axis2);

    for (size_t wsIndex = 0; wsIndex < axis2Length; ++wsIndex) {
//.........这里部分代码省略.........