/*
     <one line to give the program's name and a brief idea of what it does.>
     Copyright (C) <year>  <name of author>

     This code is distributed under the terms and conditions of the
     CCP4 licence agreement as `Part 1' (Annex 2) software.
     A copy of the CCP4 licence can be obtained by writing to the
     CCP4 Secretary, Daresbury Laboratory, Warrington WA4 4AD, UK.
*/