RebinParamsValidator.cpp

#include "MantidKernel/RebinParamsValidator.h"

namespace Mantid {
namespace Kernel {
RebinParamsValidator::RebinParamsValidator(bool allowEmpty)
    : m_allowEmpty(allowEmpty) {}

/** Check on the inputed bin boundaries and widths.
 *  @param value :: The parameter array to check
 *  @return A user level description of any problem or "" if there is no problem
 */
std::string
RebinParamsValidator::checkValidity(const std::vector<double> &value) const {
  // array must not be empty
  if (value.empty()) {
    if (m_allowEmpty) // unless allowed in the constructor
      return "";
    else
      return "Enter values for this property";
  }

  // it must have an odd number of values (and be at least 3 elements long)
  if (value.size() % 2 == 0) {
    return "The number of bin boundary parameters provided must be odd";
  }

  // bin widths must not be zero
  for (size_t i = 1; i < value.size(); i += 2) {
    if (value[i] == 0.0) {
      return "Cannot have a zero bin width";
    }
  }

  // bin boundary values must be in increasing order
  double previous = value[0];
  for (size_t i = 2; i < value.size(); i += 2) {
    if ((value[i - 1] < 0) && (previous <= 0)) {
      return "Bin boundaries must be positive for logarithmic binning";
    }
    if (value[i] <= previous) {
      return "Bin boundary values must be given in order of increasing value";
    } else
      previous = value[i];
  }

  // All's OK if we get to here
  return "";
}

} // namespace Kernel
} // namespace Mantid