Exemple #1
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/** This is a slightly "clever" method as it makes some guesses about where is best
*  to look for the right Q bin based on the fact that the input Qs (calcualted from wavelengths) tend
*  to go down while the output Qs are always in accending order
*  @param[in] OutQs the array of output Q bin boundaries, this finds the bin that contains the QIn value
*  @param[in] QToFind the Q value to find the correct bin for
*  @param[in, out] loc points to the bin boundary (in the OutQs array) whos Q is higher than QToFind and higher by the smallest amount. Algorithm starts by checking the value of loc passed and then all the bins _downwards_ through the array
*/
void Q1D2::getQBinPlus1(const MantidVec & OutQs, const double QToFind, MantidVec::const_iterator & loc) const
{
  if ( loc != OutQs.end() )
  {
    while ( loc != OutQs.begin() )
    {
      if ( (QToFind >= *(loc-1)) && (QToFind < *loc) )
      {
        return;
      }
      --loc;
    }
    if ( QToFind < *loc )
    {
      //QToFind is outside the array leave loc == OutQs.begin()
      return;
    }
  }
  else //loc == OutQs.end()
  {
    if ( OutQs.empty() || QToFind > *(loc-1) )
    {
      //outside the array leave loc == OutQs.end()
      return;
    }
  }

  // we are lost, normally the order of the Q values means we only get here on the first iteration. It's slow
  loc = std::lower_bound(OutQs.begin(), OutQs.end(), QToFind);
}
Exemple #2
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/** Calculates Sn as estimator of scale for given vector
  *
  * This method implements a naive calculation of Sn, as defined by Rousseeuw
  *and Croux (http://dx.doi.org/10.2307%2F2291267).
  * In contrast to standard deviation, this is more robust towards outliers.
  *
  * @param begin :: Beginning of vector.
  * @param end :: End of vector.
  * @return Sn of supplied data.
  */
double PoldiPeakSearch::getSn(MantidVec::const_iterator begin,
                              MantidVec::const_iterator end) const {
  size_t numberOfPoints = std::distance(begin, end);
  MantidVec absoluteDifferenceMedians(numberOfPoints);

  PARALLEL_FOR_NO_WSP_CHECK()
  for (int i = 0; i < static_cast<int>(numberOfPoints); ++i) {
    double currentValue = *(begin + i);
    MantidVec temp;
    temp.reserve(numberOfPoints - 1);
    for (int j = 0; j < static_cast<int>(numberOfPoints); ++j) {
      if (j != i) {
        temp.push_back(fabs(*(begin + j) - currentValue));
      }
    }
    std::sort(temp.begin(), temp.end());

    absoluteDifferenceMedians[i] =
        getMedianFromSortedVector(temp.begin(), temp.end());
  }

  std::sort(absoluteDifferenceMedians.begin(), absoluteDifferenceMedians.end());

  return 1.1926 * getMedianFromSortedVector(absoluteDifferenceMedians.begin(),
                                            absoluteDifferenceMedians.end());
}
Exemple #3
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/** Computes a background estimation with an error
  *
  * This method computes an estimate of the average background along with its deviation. Since the background does not
  * follow a normal distribution and may contain outliers, instead of computing the average and standard deviation,
  * the median is used as location estimator and Sn is used as scale estimator. For details regarding the latter
  * refer to PoldiPeakSearch::getSn.
  *
  * @param peakPositions :: Peak positions.
  * @param correlationCounts :: Data from which the peak positions were extracted.
  * @return Background estimation with error.
  */
UncertainValue PoldiPeakSearch::getBackgroundWithSigma(std::list<MantidVec::const_iterator> peakPositions, const MantidVec &correlationCounts) const
{
    MantidVec background = getBackground(peakPositions, correlationCounts);

    /* Instead of using Mean and Standard deviation, which are appropriate
     * for data originating from a normal distribution (which is not the case
     * for background of POLDI correlation spectra), the more robust measures
     * Median and Sn are used.
     */
    std::sort(background.begin(), background.end());
    double meanBackground = getMedianFromSortedVector(background.begin(), background.end());
    double sigmaBackground = getSn(background.begin(), background.end());

    return UncertainValue(meanBackground, sigmaBackground);
}
Exemple #4
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int UnwrapSNS::unwrapX(const MantidVec &datain, MantidVec &dataout,
                       const double &Ld) {
  MantidVec tempX_L; // lower half - to be frame wrapped
  tempX_L.reserve(m_XSize);
  tempX_L.clear();
  MantidVec tempX_U; // upper half - to not be frame wrapped
  tempX_U.reserve(m_XSize);
  tempX_U.clear();

  double filterVal = m_Tmin * Ld / m_LRef;
  dataout.clear();
  int specialBin = 0;
  for (int bin = 0; bin < m_XSize; ++bin) {
    // This is the time-of-flight value under consideration in the current
    // iteration of the loop
    const double tof = datain[bin];
    if (tof < filterVal) {
      tempX_L.push_back(tof + m_frameWidth);
      // Record the bins that fall in this range for copying over the data &
      // errors
      if (specialBin < bin)
        specialBin = bin;
    } else {
      tempX_U.push_back(tof);
    }
  } // loop over X values

  // now put it back into the vector supplied
  dataout.clear();
  dataout.insert(dataout.begin(), tempX_U.begin(), tempX_U.end());
  dataout.insert(dataout.end(), tempX_L.begin(), tempX_L.end());
  assert(datain.size() == dataout.size());

  return specialBin;
}
 MantidVec
 operator()(const MantidVec &_Left,
            const MantidVec &_Right) const { // apply operator+ to operands
   MantidVec v(_Left.size());
   std::transform(_Left.begin(), _Left.end(), _Right.begin(), v.begin(),
                  SumGaussError<double>());
   return (v);
 }
Exemple #6
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/**
 * load vectors onto a Workspace2D with 3 bins (the three components of the
 * vectors)
 * dataX for the origin of the vector (assumed (0,0,0) )
 * dataY for the tip of the vector
 * dataE is assumed (0,0,0), no errors
 * @param h5file file identifier
 * @param gws pointer to WorkspaceGroup being filled
 * @param sorting_indexes permutation of qvmod indexes to render it in
 * increasing order of momemtum transfer
 */
const MantidVec LoadSassena::loadQvectors(const hid_t &h5file,
                                          API::WorkspaceGroup_sptr gws,
                                          std::vector<int> &sorting_indexes) {

  const std::string gwsName = this->getPropertyValue("OutputWorkspace");
  const std::string setName("qvectors");

  hsize_t dims[3];
  if (dataSetInfo(h5file, setName, dims) < 0) {
    throw Kernel::Exception::FileError(
        "Unable to read " + setName + " dataset info:", m_filename);
  }
  int nq = static_cast<int>(dims[0]); // number of q-vectors
  double *buf = new double[nq * 3];
  this->dataSetDouble(h5file, "qvectors", buf);

  MantidVec qvmod; // store the modulus of the vector
  double *curr = buf;
  for (int iq = 0; iq < nq; iq++) {
    qvmod.push_back(
        sqrt(curr[0] * curr[0] + curr[1] * curr[1] + curr[2] * curr[2]));
    curr += 3;
  }

  if (getProperty("SortByQVectors")) {
    std::vector<mypair> qvmodpair;
    for (int iq = 0; iq < nq; iq++)
      qvmodpair.push_back(mypair(qvmod[iq], iq));
    std::sort(qvmodpair.begin(), qvmodpair.end(), compare);
    for (int iq = 0; iq < nq; iq++)
      sorting_indexes.push_back(qvmodpair[iq].second);
    std::sort(qvmod.begin(), qvmod.end());
  } else
    for (int iq = 0; iq < nq; iq++)
      sorting_indexes.push_back(iq);

  DataObjects::Workspace2D_sptr ws =
      boost::dynamic_pointer_cast<DataObjects::Workspace2D>(
          API::WorkspaceFactory::Instance().create("Workspace2D", nq, 3, 3));
  std::string wsName = gwsName + std::string("_") + setName;
  ws->setTitle(wsName);

  for (int iq = 0; iq < nq; iq++) {
    MantidVec &Y = ws->dataY(iq);
    const int index = sorting_indexes[iq];
    curr = buf + 3 * index;
    Y.assign(curr, curr + 3);
  }
  delete[] buf;

  ws->getAxis(0)->unit() = Kernel::UnitFactory::Instance().create(
      "MomentumTransfer"); // Set the Units

  this->registerWorkspace(
      gws, wsName, ws, "X-axis: origin of Q-vectors; Y-axis: tip of Q-vectors");
  return qvmod;
}
Exemple #7
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/** Retrieves a vector with all counts that belong to the background
  *
  * In this method, a vector is assembled which contains all count data that is
  *considered to be background.
  * Whether a point is considered background depends on its distance to the
  *given peak positions.
  *
  * @param peakPositions :: Peak positions.
  * @param correlationCounts :: Vector with the complete correlation spectrum.
  * @return Vector only with counts that belong to the background.
  */
MantidVec PoldiPeakSearch::getBackground(
    std::list<MantidVec::const_iterator> peakPositions,
    const MantidVec &correlationCounts) const {
  size_t backgroundPoints =
      getNumberOfBackgroundPoints(peakPositions, correlationCounts);

  MantidVec background;
  background.reserve(backgroundPoints);

  for (MantidVec::const_iterator point = correlationCounts.begin() + 1;
       point != correlationCounts.end() - 1; ++point) {
    if (distanceToPeaksGreaterThanMinimum(peakPositions, point)) {
      background.push_back(*point);
    }
  }

  return background;
}
/**
 * Calculate detector efficiency given a formula, the efficiency at the elastic line,
 * and a vector with energies.
 *  Efficiency = f(Ei-DeltaE) / f(Ei)
 * Hope all compilers supports the NRVO (otherwise will copy the output vector)
 * @param eff0 :: calculated eff0
 * @param formula :: formula to calculate efficiency (parsed from IDF)
 * @param xIn :: Energy bins vector (X axis)
 * @return a vector with the efficiencies
 */
MantidVec DetectorEfficiencyCorUser::calculateEfficiency(double eff0,
		const std::string& formula, const MantidVec& xIn) {

	MantidVec effOut(xIn.size() - 1); // x are bins and have more one value than y

	try {
		double e;
		mu::Parser p;
		p.DefineVar("e", &e);
		p.SetExpr(formula);

		// copied from Jaques Ollivier Code
		bool conditionForEnergy = std::min( std::abs( *std::min_element(xIn.begin(), xIn.end()) ) , m_Ei) < m_Ei;

		MantidVec::const_iterator xIn_it = xIn.begin(); // DeltaE
		MantidVec::iterator effOut_it = effOut.begin();
		for (; effOut_it != effOut.end(); ++xIn_it, ++effOut_it) {
			if (conditionForEnergy ) {
        // cppcheck cannot see that this is used by reference by muparser
        e =  std::fabs(m_Ei + *xIn_it);
			}
			else {
        // cppcheck cannot see that this is used by reference by muparser
        // cppcheck-suppress unreadVariable
				e =  std::fabs(m_Ei - *xIn_it);
			}
			double eff = p.Eval();
			*effOut_it = eff / eff0;
		}
		return effOut;
	} catch (mu::Parser::exception_type &e) {
		throw Kernel::Exception::InstrumentDefinitionError(
				"Error calculating formula from string. Muparser error message is: "
						+ e.GetMsg());
	}

}
Exemple #9
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    /**
    * Copy over the metadata from the input matrix workspace to output MDEventWorkspace
    * @param mdEventWS :: The output MDEventWorkspace where metadata are copied to. The source of the metadata is the input matrix workspace
    *
    */
    void ConvertToMD::copyMetaData(API::IMDEventWorkspace_sptr &mdEventWS) const
    {


      // found detector which is not a monitor to get proper bin boundaries.
      size_t spectra_index(0);
      bool   dector_found(false);
      for(size_t i=0;i<m_InWS2D->getNumberHistograms(); ++i)
      {
        try
        {
          auto det=m_InWS2D->getDetector(i);
          if (!det->isMonitor())
          {
            spectra_index=i;
            dector_found = true;
            g_log.debug()<<"Using spectra N "<<i<< " as the source of the bin boundaries for the resolution corrections \n"; 
            break;
          }
        }
        catch(...)
        {}
      }
      if (!dector_found)
        g_log.warning()<<"No detectors in the workspace are associated with spectra. Using spectrum 0 trying to retrieve the bin boundaries \n"; 

      // retrieve representative bin boundaries
      MantidVec binBoundaries = m_InWS2D->readX(spectra_index);
      // check if the boundaries transformation is necessary
      if (m_Convertor->getUnitConversionHelper().isUnitConverted())
      {

        if( !dynamic_cast<DataObjects::EventWorkspace *>(m_InWS2D.get()))
        {
          g_log.information()<<" ConvertToMD converts input workspace units, but the bin boundaries are copied from the first workspace spectra. The resolution estimates can be incorrect if unit conversion depends on spectra number.\n";

          UnitsConversionHelper &unitConv = m_Convertor->getUnitConversionHelper();
          unitConv.updateConversion(spectra_index);
          for(size_t i=0;i<binBoundaries.size();i++)
          {
            binBoundaries[i] =unitConv.convertUnits(binBoundaries[i]);
          }
        }
        // sort bin boundaries in case if unit transformation have swapped them.
        if (binBoundaries[0]>binBoundaries[binBoundaries.size()-1])
        {
           g_log.information()<<"Bin boundaries are not arranged monotonously. Sorting performed\n"; 
           std::sort(binBoundaries.begin(),binBoundaries.end());
        }
      }

      // Replacement for SpectraDetectorMap::createIDGroupsMap using the ISpectrum objects instead
      auto mapping = boost::make_shared<det2group_map>();
      for ( size_t i = 0; i < m_InWS2D->getNumberHistograms(); ++i )
      {
        const auto& dets = m_InWS2D->getSpectrum(i)->getDetectorIDs();
        if(!dets.empty())
        {
          std::vector<detid_t> id_vector;
          std::copy(dets.begin(), dets.end(), std::back_inserter(id_vector));
          mapping->insert(std::make_pair(id_vector.front(), id_vector));
        }
      }

      uint16_t nexpts = mdEventWS->getNumExperimentInfo();
      for(uint16_t i = 0; i < nexpts; ++i)
      {
        ExperimentInfo_sptr expt = mdEventWS->getExperimentInfo(i);
        expt->mutableRun().storeHistogramBinBoundaries(binBoundaries);
        expt->cacheDetectorGroupings(*mapping);
      }


    }
Exemple #10
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/** Subtracts a constant from the data values in the given workspace
 *  @param Y :: The vector from which to subtract
 *  @param value :: The value to subtract from each data point
 */
void IQTransform::subtractBackgroundValue(MantidVec& Y, const double value)
{
  g_log.debug() << "Subtracting the background value " << value << " from the input workspace.\n";
  std::transform(Y.begin(),Y.end(),Y.begin(),std::bind2nd(std::minus<double>(),value));
}
Exemple #11
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void PoldiPeakSearch::exec() {
  g_log.information() << "PoldiPeakSearch:" << std::endl;

  Workspace2D_sptr correlationWorkspace = getProperty("InputWorkspace");
  MantidVec correlationQValues = correlationWorkspace->readX(0);
  MantidVec correlatedCounts = correlationWorkspace->readY(0);
  g_log.information() << "   Auto-correlation data read." << std::endl;

  Unit_sptr xUnit = correlationWorkspace->getAxis(0)->unit();

  if (xUnit->caption() == "") {
    g_log.information()
        << "   Workspace does not have unit, defaulting to MomentumTransfer."
        << std::endl;

    xUnit = UnitFactory::Instance().create("MomentumTransfer");
  } else {
    g_log.information() << "   Unit of workspace is " << xUnit->caption() << "."
                        << std::endl;
  }

  setMinimumDistance(getProperty("MinimumPeakSeparation"));
  setMinimumPeakHeight(getProperty("MinimumPeakHeight"));
  setMaximumPeakNumber(getProperty("MaximumPeakNumber"));

  if (m_doubleMinimumDistance > static_cast<int>(correlatedCounts.size())) {
    throw(std::runtime_error("MinimumPeakSeparation is smaller than number of "
                             "spectrum points - no peaks possible."));
  }

  g_log.information() << "   Parameters set." << std::endl;

  MantidVec summedNeighborCounts = getNeighborSums(correlatedCounts);
  g_log.information() << "   Neighboring counts summed, contains "
                      << summedNeighborCounts.size() << " data points."
                      << std::endl;

  std::list<MantidVec::const_iterator> peakPositionsSummed =
      findPeaks(summedNeighborCounts.begin(), summedNeighborCounts.end());
  g_log.information() << "   Peaks detected in summed spectrum: "
                      << peakPositionsSummed.size() << std::endl;

  /* This step is required because peaks are actually searched in the
   * "sum-of-neighbors"-spectrum.
   * The mapping removes the offset from the peak position which results from
   * different beginning
   * of this vector compared to the original correlation counts.
   */
  std::list<MantidVec::const_iterator> peakPositionsCorrelation =
      mapPeakPositionsToCorrelationData(peakPositionsSummed,
                                        summedNeighborCounts.begin(),
                                        correlatedCounts.begin());
  g_log.information() << "   Peak positions transformed to original spectrum."
                      << std::endl;

  /* Since intensities are required for filtering, they are extracted from the
   * original count data,
   * along with the Q-values.
   */
  std::vector<PoldiPeak_sptr> peakCoordinates =
      getPeaks(correlatedCounts.begin(), correlatedCounts.end(),
               peakPositionsCorrelation, correlationQValues, xUnit);
  g_log.information()
      << "   Extracted peak positions in Q and intensity guesses." << std::endl;

  UncertainValue backgroundWithSigma =
      getBackgroundWithSigma(peakPositionsCorrelation, correlatedCounts);
  g_log.information() << "   Calculated average background and deviation: "
                      << UncertainValueIO::toString(backgroundWithSigma)
                      << std::endl;

  if ((*getProperty("MinimumPeakHeight")).isDefault()) {
    setMinimumPeakHeight(minimumPeakHeightFromBackground(backgroundWithSigma));
  }

  std::vector<PoldiPeak_sptr> intensityFilteredPeaks(peakCoordinates.size());
  auto newEnd = std::remove_copy_if(
      peakCoordinates.begin(), peakCoordinates.end(),
      intensityFilteredPeaks.begin(),
      boost::bind(&PoldiPeakSearch::isLessThanMinimum, this, _1));
  intensityFilteredPeaks.resize(
      std::distance(intensityFilteredPeaks.begin(), newEnd));

  g_log.information() << "   Peaks above minimum intensity ("
                      << m_minimumPeakHeight
                      << "): " << intensityFilteredPeaks.size() << std::endl;

  std::sort(intensityFilteredPeaks.begin(), intensityFilteredPeaks.end(),
            boost::bind<bool>(&PoldiPeak::greaterThan, _1, _2,
                              &PoldiPeak::intensity));

  for (std::vector<PoldiPeak_sptr>::const_iterator peak =
           intensityFilteredPeaks.begin();
       peak != intensityFilteredPeaks.end(); ++peak) {
    m_peaks->addPeak(*peak);
  }

  /* The derived background error is set as error in the workspace containing
   * correlation data, so it may be used as weights for peak fitting later on.
   */
  setErrorsOnWorkspace(correlationWorkspace, backgroundWithSigma.error());

  setProperty("OutputWorkspace", m_peaks->asTableWorkspace());
}
Exemple #12
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void LoadDaveGrp::exec()
{
  const std::string filename = this->getProperty("Filename");

  int yLength = 0;

  MantidVec *xAxis = new MantidVec();
  MantidVec *yAxis = new MantidVec();

  std::vector<MantidVec *> data;
  std::vector<MantidVec *> errors;

  this->ifile.open(filename.c_str());
  if (this->ifile.is_open())
  {
    // Size of x axis
    this->getAxisLength(this->xLength);
    // Size of y axis
    this->getAxisLength(yLength);
    // This is also the number of groups (spectra)
    this->nGroups = yLength;
    // Read in the x axis values
    this->getAxisValues(xAxis, static_cast<std::size_t>(this->xLength));
    // Read in the y axis values
    this->getAxisValues(yAxis, static_cast<std::size_t>(yLength));
    // Read in the data
    this->getData(data, errors);
  }
  this->ifile.close();

  // Scale the x-axis if it is in micro-eV to get it to meV
  const bool isUeV = this->getProperty("IsMicroEV");
  if (isUeV)
  {
    MantidVec::iterator iter;
    for (iter = xAxis->begin(); iter != xAxis->end(); ++iter)
    {
      *iter /= 1000.0;
    }
  }

  // Create workspace
  API::MatrixWorkspace_sptr outputWorkspace = \
      boost::dynamic_pointer_cast<API::MatrixWorkspace>\
      (API::WorkspaceFactory::Instance().create("Workspace2D", this->nGroups,
      this->xLength, yLength));
  // Force the workspace to be a distribution
  outputWorkspace->isDistribution(true);

  // Set the x-axis units
  outputWorkspace->getAxis(0)->unit() = Kernel::UnitFactory::Instance().create(this->getProperty("XAxisUnits"));

  API::Axis* const verticalAxis = new API::NumericAxis(yLength);
  // Set the y-axis units
  verticalAxis->unit() = Kernel::UnitFactory::Instance().create(this->getProperty("YAxisUnits"));

  outputWorkspace->replaceAxis(1, verticalAxis);

  for(int i = 0; i < this->nGroups; i++)
  {
    outputWorkspace->dataX(i) = *xAxis;
    outputWorkspace->dataY(i) = *data[i];
    outputWorkspace->dataE(i) = *errors[i];
    verticalAxis->setValue(i, yAxis->at(i));

    delete data[i];
    delete errors[i];
  }

  delete xAxis;
  delete yAxis;

  outputWorkspace->mutableRun().addProperty("Filename",filename);
  this->setProperty("OutputWorkspace", outputWorkspace);
}
Exemple #13
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/** Finds the index in an ordered vector which follows the given value
 *  @param value :: The value to search for
 *  @param vec ::   The vector to search
 *  @return The index (will give vec.size()+1 if the value is past the end of the vector)
 */
int RemoveBins::findIndex(const double& value, const MantidVec& vec)
{
  MantidVec::const_iterator pos = std::lower_bound(vec.begin(),vec.end(),value);
  return static_cast<int>(pos-vec.begin());
}