SphinxExamples/src/Core/Common/CovariantVectorNorm/Code.cxx

/*=========================================================================
 *
 *  Copyright NumFOCUS
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *         https://www.apache.org/licenses/LICENSE-2.0.txt
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 *=========================================================================*/
 
#include "itkCovariantVector.h"
 
int
main()
{
  using VectorType = itk::CovariantVector<double, 3>;
  VectorType v;
  v[0] = 1.0;
  v[1] = 2.0;
  v[2] = 3.0;
 
  std::cout << "v: " << v << std::endl;
 
  // norm
  VectorType::RealValueType vnorm = v.GetNorm();
  std::cout << "vnorm: " << vnorm << std::endl;
 
  VectorType::RealValueType vnorm2 = v.GetSquaredNorm();
  std::cout << "vnorm2: " << vnorm2 << std::endl;
 
  VectorType u = v;
 
  // normalization
  v.Normalize();
  std::cout << "v: " << v << std::endl;
 
  // another way to normalize
  if (vnorm != 0.)
  {
    for (unsigned int i = 0; i < u.GetNumberOfComponents(); ++i)
    {
      u[i] /= vnorm;
    }
  }
 
  std::cout << "u: " << u << std::endl;
 
  if ((u - v).GetNorm() != 0.)
  {
    return EXIT_FAILURE;
  }
 
  return EXIT_SUCCESS;
}