C++ MatrixWorkspace_sptr::isHistogramData方法代码示例

/** Executes the algorithm
 *
 */
void SplineBackground::exec()
{

  API::MatrixWorkspace_sptr inWS = getProperty("InputWorkspace");
  int spec = getProperty("WorkspaceIndex");

  if (spec > static_cast<int>(inWS->getNumberHistograms()))
    throw std::out_of_range("WorkspaceIndex is out of range.");

  const MantidVec& X = inWS->readX(spec);
  const MantidVec& Y = inWS->readY(spec);
  const MantidVec& E = inWS->readE(spec);
  const bool isHistogram = inWS->isHistogramData();

  const int ncoeffs = getProperty("NCoeff");
  const int k = 4; // order of the spline + 1 (cubic)
  const int nbreak = ncoeffs - (k - 2);

  if (nbreak <= 0)
    throw std::out_of_range("Too low NCoeff");

  gsl_bspline_workspace *bw;
  gsl_vector *B;

  gsl_vector *c, *w, *x, *y;
  gsl_matrix *Z, *cov;
  gsl_multifit_linear_workspace *mw;
  double chisq;

  int n = static_cast<int>(Y.size());
  bool isMasked = inWS->hasMaskedBins(spec);
  std::vector<int> masked(Y.size());
  if (isMasked)
  {
    for(API::MatrixWorkspace::MaskList::const_iterator it=inWS->maskedBins(spec).begin();it!=inWS->maskedBins(spec).end();++it)
      masked[it->first] = 1;
    n -= static_cast<int>(inWS->maskedBins(spec).size());
  }

  if (n < ncoeffs)
  {
    g_log.error("Too many basis functions (NCoeff)");
    throw std::out_of_range("Too many basis functions (NCoeff)");
  }

  /* allocate a cubic bspline workspace (k = 4) */
  bw = gsl_bspline_alloc(k, nbreak);
  B = gsl_vector_alloc(ncoeffs);

  x = gsl_vector_alloc(n);
  y = gsl_vector_alloc(n);
  Z = gsl_matrix_alloc(n, ncoeffs);
  c = gsl_vector_alloc(ncoeffs);
  w = gsl_vector_alloc(n);
  cov = gsl_matrix_alloc(ncoeffs, ncoeffs);
  mw = gsl_multifit_linear_alloc(n, ncoeffs);

  /* this is the data to be fitted */
  int j = 0;
  for (MantidVec::size_type i = 0; i < Y.size(); ++i)
  {
    if (isMasked && masked[i]) continue;
    gsl_vector_set(x, j, (isHistogram ? (0.5*(X[i]+X[i+1])) : X[i])); // Middle of the bins, if a histogram
    gsl_vector_set(y, j, Y[i]);
    gsl_vector_set(w, j, E[i]>0.?1./(E[i]*E[i]):0.);

    ++j;
  }

  if (n != j)
  {
    gsl_bspline_free(bw);
    gsl_vector_free(B);
    gsl_vector_free(x);
    gsl_vector_free(y);
    gsl_matrix_free(Z);
    gsl_vector_free(c);
    gsl_vector_free(w);
    gsl_matrix_free(cov);
    gsl_multifit_linear_free(mw);

    throw std::runtime_error("Assertion failed: n != j");
  }

  double xStart = X.front();
  double xEnd =   X.back();

  /* use uniform breakpoints */
  gsl_bspline_knots_uniform(xStart, xEnd, bw);

  /* construct the fit matrix X */
  for (int i = 0; i < n; ++i)
  {
    double xi=gsl_vector_get(x, i);

    /* compute B_j(xi) for all j */
    gsl_bspline_eval(xi, B, bw);
//.........这里部分代码省略.........

/**
 * Execute smoothing of a single spectrum.
 * @param inputWS :: A workspace to pick a spectrum from.
 * @param wsIndex :: An index of a spectrum to smooth.
 * @return :: A single-spectrum workspace with the smoothed data.
 */
API::MatrixWorkspace_sptr
WienerSmooth::smoothSingleSpectrum(API::MatrixWorkspace_sptr inputWS,
                                   size_t wsIndex) {
  size_t dataSize = inputWS->blocksize();

  // it won't work for very small workspaces
  if (dataSize < 4) {
    g_log.debug() << "No smoothing, spectrum copied." << std::endl;
    return copyInput(inputWS, wsIndex);
  }

  // Due to the way RealFFT works the input should be even-sized
  const bool isOddSize = dataSize % 2 != 0;
  if (isOddSize) {
    // add a fake value to the end to make size even
    inputWS = copyInput(inputWS, wsIndex);
    wsIndex = 0;
    auto &X = inputWS->dataX(wsIndex);
    auto &Y = inputWS->dataY(wsIndex);
    auto &E = inputWS->dataE(wsIndex);
    double dx = X[dataSize - 1] - X[dataSize - 2];
    X.push_back(X.back() + dx);
    Y.push_back(Y.back());
    E.push_back(E.back());
  }

  // the input vectors
  auto &X = inputWS->readX(wsIndex);
  auto &Y = inputWS->readY(wsIndex);
  auto &E = inputWS->readE(wsIndex);

  // Digital fourier transform works best for data oscillating around 0.
  // Fit a spline with a small number of break points to the data.
  // Make sure that the spline passes through the first and the last points
  // of the data.
  // The fitted spline will be subtracted from the data and the difference
  // will be smoothed with the Wiener filter. After that the spline will be
  // added to the smoothed data to produce the output.

  // number of spline break points, must be smaller than the data size but
  // between 2 and 10
  size_t nbreak = 10;
  if (nbreak * 3 > dataSize)
    nbreak = dataSize / 3;

  // NB. The spline mustn't fit too well to the data. If it does smoothing
  // doesn't happen.
  // TODO: it's possible that the spline is unnecessary and a simple linear
  // function will
  //       do a better job.

  g_log.debug() << "Spline break points " << nbreak << std::endl;

  // define the spline
  API::IFunction_sptr spline =
      API::FunctionFactory::Instance().createFunction("BSpline");
  auto xInterval = getStartEnd(X, inputWS->isHistogramData());
  spline->setAttributeValue("StartX", xInterval.first);
  spline->setAttributeValue("EndX", xInterval.second);
  spline->setAttributeValue("NBreak", static_cast<int>(nbreak));
  // fix the first and last parameters to the first and last data values
  spline->setParameter(0, Y.front());
  spline->fix(0);
  size_t lastParamIndex = spline->nParams() - 1;
  spline->setParameter(lastParamIndex, Y.back());
  spline->fix(lastParamIndex);

  // fit the spline to the data
  auto fit = createChildAlgorithm("Fit");
  fit->initialize();
  fit->setProperty("Function", spline);
  fit->setProperty("InputWorkspace", inputWS);
  fit->setProperty("WorkspaceIndex", static_cast<int>(wsIndex));
  fit->setProperty("CreateOutput", true);
  fit->execute();

  // get the fit output workspace; spectrum 2 contains the difference that is to
  // be smoothed
  API::MatrixWorkspace_sptr fitOut = fit->getProperty("OutputWorkspace");

  // Fourier transform the difference spectrum
  auto fourier = createChildAlgorithm("RealFFT");
  fourier->initialize();
  fourier->setProperty("InputWorkspace", fitOut);
  fourier->setProperty("WorkspaceIndex", 2);
  // we don't require bin linearity as we don't need the exact transform
  fourier->setProperty("IgnoreXBins", true);
  fourier->execute();

  API::MatrixWorkspace_sptr fourierOut =
      fourier->getProperty("OutputWorkspace");

  // spectrum 2 of the transformed workspace has the transform modulus which is
  // a square
//.........这里部分代码省略.........