EvaluateMDFunction.cpp

// 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 "MantidMDAlgorithms/EvaluateMDFunction.h"
#include "MantidAPI/AlgorithmManager.h"
#include "MantidAPI/FunctionDomainMD.h"
#include "MantidAPI/FunctionProperty.h"
#include "MantidAPI/FunctionValues.h"
#include "MantidAPI/IMDHistoWorkspace.h"
#include "MantidAPI/IMDIterator.h"

namespace Mantid::MDAlgorithms {

using Mantid::API::WorkspaceProperty;
using Mantid::Kernel::Direction;

// Register the algorithm into the AlgorithmFactory
DECLARE_ALGORITHM(EvaluateMDFunction)

//----------------------------------------------------------------------------------------------
/** Constructor
 */
EvaluateMDFunction::EvaluateMDFunction() { useAlgorithm("EvaluateFunction"); }

//----------------------------------------------------------------------------------------------

/// Algorithm's version for identification. @see Algorithm::version
int EvaluateMDFunction::version() const { return 1; }

/// Algorithm's category for identification. @see Algorithm::category
const std::string EvaluateMDFunction::category() const { return "MDAlgorithms\\Creation"; }

/// Algorithm's summary for use in the GUI and help. @see Algorithm::summary
const std::string EvaluateMDFunction::summary() const { return "Evaluates an MD function on a MD histo workspace."; }

//----------------------------------------------------------------------------------------------
/** Initialize the algorithm's properties.
 */
void EvaluateMDFunction::init() {
  declareProperty(std::make_unique<WorkspaceProperty<API::IMDHistoWorkspace>>("InputWorkspace", "", Direction::Input),
                  "An input workspace that provides dimensions for the output.");
  declareProperty(std::make_unique<API::FunctionProperty>("Function", Direction::InOut),
                  "Parameters defining the fitting function and its initial values");
  declareProperty(std::make_unique<WorkspaceProperty<API::IMDHistoWorkspace>>("OutputWorkspace", "", Direction::Output),
                  "An output workspace.");
}

//----------------------------------------------------------------------------------------------
/** Execute the algorithm.
 */
void EvaluateMDFunction::exec() {
  API::IMDHistoWorkspace_sptr input = getProperty("InputWorkspace");

  auto cloner = API::AlgorithmManager::Instance().create("CloneMDWorkspace");
  cloner->initialize();
  cloner->setChild(true);
  cloner->setProperty("InputWorkspace", input);
  cloner->setPropertyValue("OutputWorkspace", "_");
  cloner->execute();

  API::IMDWorkspace_sptr clone = cloner->getProperty("OutputWorkspace");
  API::IMDHistoWorkspace_sptr output = std::dynamic_pointer_cast<API::IMDHistoWorkspace>(clone);

  if (!output)
    throw std::runtime_error("Cannot create output workspace");

  API::IFunction_sptr function = getProperty("Function");
  function->setWorkspace(output);

  API::FunctionDomainMD domain(output);
  API::FunctionValues values(domain);

  function->function(domain, values);

  double *data = values.getPointerToCalculated(0);
  size_t length = values.size();
  auto outputData = output->mutableSignalArray();
  std::copy(data, data + length, outputData);

  setProperty("OutputWorkspace", output);
}

} // namespace Mantid::MDAlgorithms