text: #
  # Copyright The NOMAD Authors.
  #
  # This file is part of NOMAD.
  # See https://nomad-lab.eu for further info.
  #
  # 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
  #
  #     http://www.apache.org/licenses/LICENSE-2.0
  #
  # 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.
  #
  
  import re
  import numpy as np
  
  from nomad.units import ureg
  from nomad.parsing.file_parser import BasicParser
  
  
  class NAMDParser(BasicParser):
      def __init__(self):
          re_f = r'\-*\d+\.\d+E*e*\-*\+*\d*'
  
          def get_positions(val):
              try:
                  labels, positions = zip(*re.findall(rf'ATOM +\d+ +([A-Z])\w* +\w+ +\d+ +({re_f} +{re_f} +{re_f})', val))
                  positions = np.array([v.split() for v in positions], dtype=np.dtype(np.float64))
                  return dict(atom_labels=labels, atom_positions=positions)
              except Exception:
                  return dict()
  
          super().__init__(
              specifications=dict(
                  name='parsers/namd', code_name='Namd', domain='dft',
                  mainfile_contents_re=r'\s*Info:\s*NAMD\s*[0-9.]+\s*for\s*',
                  mainfile_mime_re=r'text/.*'),
              units_mapping=dict(length=ureg.angstrom, energy=ureg.kcal / 6.02214076e+23),
              auxilliary_files=r'Info\: COORDINATE PDB +(\S+\.pdb)',
              # due to auto type conversion, we need to include NAMD to make it string
              program_version=r'Info\: (NAMD [\d\.]+) for',
              atom_labels_atom_positions=(rf'(ATOM +\d+ +\w+ +\w+ +\d+ +{re_f}[\s\S]+?)END', get_positions),
              energy_total=(rf'ENERGY\: +(\d+ +{re_f}.+)', lambda x: x.split()[10]))
  