//  $Id: mmdb_atom.cpp $
//  =================================================================
//
//   CCP4 Coordinate Library: support of coordinate-related
//   functionality in protein crystallography applications.
//
//   Copyright (C) Eugene Krissinel 2000-2013.
//
//    This library is free software: you can redistribute it and/or
//    modify it under the terms of the GNU Lesser General Public
//    License version 3, modified in accordance with the provisions
//    of the license to address the requirements of UK law.
//
//    You should have received a copy of the modified GNU Lesser
//    General Public License along with this library. If not, copies
//    may be downloaded from http://www.ccp4.ac.uk/ccp4license.php
//
//    This program is distributed in the hope that it will be useful,
//    but WITHOUT ANY WARRANTY; without even the implied warranty of
//    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//    GNU Lesser General Public License for more details.
//
//  =================================================================
//
//    18.10.13   <--  Date of Last Modification.
//                   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
//  -----------------------------------------------------------------
//
//  **** Module  :  MMDB_Atom <implementation>
//       ~~~~~~~~~
//  **** Project :  MacroMolecular Data Base (MMDB)
//       ~~~~~~~~~
//  **** Classes :  mmdb::Atom     ( atom class    )
//       ~~~~~~~~~  mmdb::Residue  ( residue class )
//  **** Functions: mmdb::BondAngle
//       ~~~~~~~~~~
//
//  Copyright (C) E. Krissinel 2000-2013
//
//  =================================================================
//

#include <string.h>
#include <stdlib.h>
#include <math.h>

#include "mmdb_chain.h"
#include "mmdb_model.h"
#include "mmdb_root.h"
#include "mmdb_tables.h"
#include "mmdb_cifdefs.h"
#include "hybrid_36.h"


namespace mmdb  {

  //  ================================================================

  #define  ASET_ShortBinary   0x10000000
  #define  ASET_ShortTer      0x20000000
  #define  ASET_ShortHet      0x40000000

  bool  ignoreSegID            = false;
  bool  ignoreElement          = false;
  bool  ignoreCharge           = false;
  bool  ignoreNonCoorPDBErrors = false;
  bool  ignoreUnmatch          = false;


  //  ==========================  Atom  =============================

  Atom::Atom() : UDData()  {
    InitAtom();
  }

  Atom::Atom ( PResidue res ) : UDData()  {
    InitAtom();
    if (res)
      res->AddAtom ( this );
  }

  Atom::Atom ( io::RPStream Object ) : UDData(Object)  {
    InitAtom();
  }

  Atom::~Atom()  {
  PPAtom A;
  int    nA;
    FreeMemory();
    if (residue)  {
      A  = NULL;
      nA = 0;
      if (residue->chain)  {
        if (residue->chain->model)  {
          A  = residue->chain->model->GetAllAtoms();
          nA = residue->chain->model->GetNumberOfAllAtoms();
        }
      }
      residue->_ExcludeAtom ( index );
      if ((0<index) && (index<=nA))  A[index-1] = NULL;
    }
  }

  void  Atom::InitAtom()  {
    serNum     = -1;         // serial number
    index      = -1;         // index in the file
    name[0]    = char(0);    // atom name
    label_atom_id[0] = char(0); // assigned atom name (not aligned)
    altLoc[0]  = char(0);    // alternate location indicator
    residue    = NULL;       // reference to residue
    x          = 0.0;        // orthogonal x-coordinate in angstroms
    y          = 0.0;        // orthogonal y-coordinate in angstroms
    z          = 0.0;        // orthogonal z-coordinate in angstroms
    occupancy  = 0.0;        // occupancy
    tempFactor = 0.0;        // temperature factor
    segID[0]   = char(0);    // segment identifier
    strcpy ( element,"  " ); // chemical element symbol - RIGHT JUSTIFIED
    energyType[0] = char(0); // chemical element symbol - RIGHT JUSTIFIED
    charge     = 0.0;        // charge on the atom
    sigX       = 0.0;        // standard deviation of the stored x-coord
    sigY       = 0.0;        // standard deviation of the stored y-coord
    sigZ       = 0.0;        // standard deviation of the stored z-coord
    sigOcc     = 0.0;        // standard deviation of occupancy
    sigTemp    = 0.0;        // standard deviation of temperature factor
    u11        = 0.0;        //
    u22        = 0.0;        // anisotropic
    u33        = 0.0;        //
    u12        = 0.0;        //    temperature
    u13        = 0.0;        //
    u23        = 0.0;        //        factors
    su11       = 0.0;        //
    su22       = 0.0;        // standard
    su33       = 0.0;        //    deviations of
    su12       = 0.0;        //       anisotropic
    su13       = 0.0;        //          temperature
    su23       = 0.0;        //             factors
    Het        = false;      // indicator of atom in non-standard groups
    Ter        = false;      // chain terminator
    WhatIsSet  = 0x00000000; // nothing is set
    nBonds     = 0;          // no bonds
    Bond       = NULL;       // empty array of bonds
  }

  void  Atom::FreeMemory()  {
    FreeBonds();
  }

  void  Atom::FreeBonds()  {
    if (Bond)  delete[] Bond;
    Bond   = NULL;
    nBonds = 0;
  }

  int Atom::GetNBonds()  {
    return nBonds & 0x000000FF;
  }

  void Atom::GetBonds ( RPAtomBond atomBond, int & nAtomBonds )  {
  //    This GetBonds(..) returns pointer to the Atom's
  //  internal Bond structure, IT MUST NOT BE DISPOSED.
    nAtomBonds = nBonds & 0x000000FF;
    atomBond   = Bond;
  }

  void Atom::GetBonds ( RPAtomBondI atomBondI, int & nAtomBonds )  {
  //    This GetBonds(..) disposes AtomBondI, if it was not set
  //  to NULL, allocates AtomBondI[nAtomBonds] and returns its
  //  pointer. AtomBondI MUST BE DISPOSED BY APPLICATION.
  int i;

    if (atomBondI)  delete[] atomBondI;

    nAtomBonds = nBonds & 0x000000FF;

    if (nAtomBonds<=0)
      atomBondI = NULL;
    else  {
      atomBondI = new AtomBondI[nAtomBonds];
      for (i=0;i<nAtomBonds;i++) {
        if (Bond[i].atom)
              atomBondI[i].index = Bond[i].atom->index;
        else  atomBondI[i].index = -1;
        atomBondI[i].order = Bond[i].order;
      }

    }

  }

  void Atom::GetBonds ( PAtomBondI AtomBondI, int & nAtomBonds,
                         int maxlength )  {
  //    This GetBonds(..) does not dispose or allocate AtomBond.
  //  It is assumed that length of AtomBond is sufficient to
  //  accomodate all bonded atoms.
  int  i;

    nAtomBonds = IMin(maxlength,nBonds & 0x000000FF);

    for (i=0;i<nAtomBonds;i++)  {
      if (Bond[i].atom)
            AtomBondI[i].index = Bond[i].atom->index;
      else  AtomBondI[i].index = -1;
      AtomBondI[i].order = Bond[i].order;
    }

  }


  int  Atom::AddBond ( PAtom bond_atom, int bond_order,
                        int nAdd_bonds )  {
  PAtomBond B1;
  int        i,k,nb,nballoc;

    nb = nBonds & 0x000000FF;
    k  = -1;
    for (i=0;(i<nb) && (k<0);i++)
      if (Bond[i].atom==bond_atom)  k = i;
    if (k>=0)  return -k;

    nballoc = (nBonds >> 8) & 0x000000FF;
    if (nBonds>=nballoc)  {
      nballoc += nAdd_bonds;
      B1 = new AtomBond[nballoc];
      for (i=0;i<nb;i++)  {
        B1[i].atom  = Bond[i].atom;
        B1[i].order = Bond[i].order;
      }
      if (Bond)  delete[] Bond;
      Bond = B1;
    }
    Bond[nb].atom  = bond_atom;
    Bond[nb].order = bond_order;
    nb++;

    nBonds = nb | (nballoc << 8);

    return nb;

  }

  void  Atom::SetResidue ( PResidue res )  {
    residue = res;
  }

  void  Atom::StandardPDBOut ( cpstr Record, pstr S )  {
  char N[10];
    strcpy    ( S,Record );
    PadSpaces ( S,80     );
    if (serNum>99999)  {
      hy36encode ( 5,serNum,N );
      strcpy_n   ( &(S[6]),N,5 );
    } else if (serNum>0)
      PutInteger ( &(S[6]),serNum,5 );
    else if (index<=99999)
      PutInteger ( &(S[6]),index,5 );
    else {
      hy36encode ( 5,index,N );
      strcpy_n   ( &(S[6]),N,5 );
    }
    if (!Ter)  {
      if (altLoc[0])  S[16] = altLoc[0];
      strcpy_n  ( &(S[12]),name   ,4 );
      strcpy_n  ( &(S[72]),segID  ,4 );
      strcpy_nr ( &(S[76]),element,2 );
      if (WhatIsSet & ASET_Charge)  {
        if (charge>0)       sprintf ( N,"%1i+",mround(charge)  );
        else if (charge<0)  sprintf ( N,"%1i-",mround(-charge) );
                      else  strcpy  ( N,"  " );
        strcpy_n ( &(S[78]),N,2 );
      } else
        strcpy_n ( &(S[78]),"  ",2 );
    }
    strcpy_nr ( &(S[17]),residue->name,3 );
    strcpy_nr ( &(S[20]),residue->chain->chainID,2 );
    if (residue->seqNum>MinInt4)  {
      if ((-999<=residue->seqNum) && (residue->seqNum<=9999))
        PutIntIns  ( &(S[22]),residue->seqNum,4,residue->insCode );
      else  {
        hy36encode ( 4,residue->seqNum,N );
        strcpy_n   ( &(S[22]),N,4 );
      }
    }
  }

  void  Atom::PDBASCIIDump ( io::RFile f )  {
  // makes the ASCII PDB  ATOM, HETATM, SIGATOM, ANISOU
  // SIGUIJ and TER lines from the class' data
  char S[100];
    if (Ter)  {
      if (WhatIsSet & ASET_Coordinates)  {
        StandardPDBOut ( pstr("TER"),S );
        f.WriteLine ( S );
      }
    } else  {
      if (WhatIsSet & ASET_Coordinates)  {
        if (Het)  StandardPDBOut ( pstr("HETATM"),S );
            else  StandardPDBOut ( pstr("ATOM")  ,S );
        PutRealF ( &(S[30]),x,8,3 );
        PutRealF ( &(S[38]),y,8,3 );
        PutRealF ( &(S[46]),z,8,3 );
        if (WhatIsSet & ASET_Occupancy)
          PutRealF ( &(S[54]),occupancy ,6,2 );
        if (WhatIsSet & ASET_tempFactor)
          PutRealF ( &(S[60]),tempFactor,6,2 );
        f.WriteLine ( S );
      }
      if (WhatIsSet & ASET_CoordSigma)  {
        StandardPDBOut ( pstr("SIGATM"),S );
        PutRealF ( &(S[30]),sigX,8,3 );
        PutRealF ( &(S[38]),sigY,8,3 );
        PutRealF ( &(S[46]),sigZ,8,3 );
        if ((WhatIsSet & ASET_OccSigma) &&
            (WhatIsSet & ASET_Occupancy))
          PutRealF ( &(S[54]),sigOcc,6,2 );
        if ((WhatIsSet & ASET_tFacSigma) &&
            (WhatIsSet & ASET_tempFactor))
          PutRealF ( &(S[60]),sigTemp,6,2 );
        f.WriteLine ( S );
      }
      if (WhatIsSet & ASET_Anis_tFac)  {
        StandardPDBOut ( pstr("ANISOU"),S );
        PutInteger  ( &(S[28]),mround(u11*1.0e4),7 );
        PutInteger  ( &(S[35]),mround(u22*1.0e4),7 );
        PutInteger  ( &(S[42]),mround(u33*1.0e4),7 );
        PutInteger  ( &(S[49]),mround(u12*1.0e4),7 );
        PutInteger  ( &(S[56]),mround(u13*1.0e4),7 );
        PutInteger  ( &(S[63]),mround(u23*1.0e4),7 );
        f.WriteLine ( S );
        if (WhatIsSet & ASET_Anis_tFSigma)  {
          StandardPDBOut ( pstr("SIGUIJ"),S );
          PutInteger  ( &(S[28]),mround(su11*1.0e4),7 );
          PutInteger  ( &(S[35]),mround(su22*1.0e4),7 );
          PutInteger  ( &(S[42]),mround(su33*1.0e4),7 );
          PutInteger  ( &(S[49]),mround(su12*1.0e4),7 );
          PutInteger  ( &(S[56]),mround(su13*1.0e4),7 );
          PutInteger  ( &(S[63]),mround(su23*1.0e4),7 );
          f.WriteLine ( S );
        }
      }
    }
  }

  void  Atom::MakeCIF ( mmcif::PData CIF )  {
  mmcif::PLoop Loop;
  AtomName     AtName;
  Element      el;
  char         N[10];
  int          i,j,RC;
  PChain       chain       = NULL;
  PModel       model       = NULL;
  //bool      singleModel = true;

    if (residue)  chain = residue->chain;
    if (chain)    model = PModel(chain->model);
  //  if (model)  {
  //    if (model->manager)
  //      singleModel = PRoot(model->manager)->nModels<=1;
  //  }

  /*

  loop_
  *0  _atom_site.group_PDB
  *1  _atom_site.id
  *2  _atom_site.type_symbol         <- chem elem
  -3  _atom_site.label_atom_id       <- atom name
  *4  _atom_site.label_alt_id        <- alt code
  =5  _atom_site.label_comp_id       <- res name ???
  =6  _atom_site.label_asym_id       <- chain id ???
  =7  _atom_site.label_entity_id     < ???
  =8  _atom_site.label_seq_id        <- poly seq id
  +9  _atom_site.pdbx_PDB_ins_code   <- ins code
  -10 _atom_site.segment_id          <- segment id
  *11 _atom_site.Cartn_x
  *12 _atom_site.Cartn_y
  *13 _atom_site.Cartn_z
  *14 _atom_site.occupancy
  *15 _atom_site.B_iso_or_equiv
  *16 _atom_site.Cartn_x_esd
  *17 _atom_site.Cartn_y_esd
  *18 _atom_site.Cartn_z_esd
  *19 _atom_site.occupancy_esd
  *20 _atom_site.B_iso_or_equiv_esd
  *21 _atom_site.pdbx_formal_charge
  +22 _atom_site.auth_seq_id          <- seq id we want
  +23 _atom_site.auth_comp_id         <- res name we want
  +24 _atom_site.auth_asym_id         <- ch id we want ?
  *25 _atom_site.auth_atom_id         <- atom name we want ?
  +26 _atom_site.pdbx_PDB_model_num   <- model no

  '+' is read in Root::CheckAtomPlace()
  '=' new in residue
  '-' new in atom


  */

    RC = CIF->AddLoop ( CIFCAT_ATOM_SITE,Loop );
    if (RC!=mmcif::CIFRC_Ok)  {
      // the category was (re)created, provide tags

      Loop->AddLoopTag ( CIFTAG_GROUP_PDB          ); // ATOM, TER etc.
      Loop->AddLoopTag ( CIFTAG_ID                 ); // serial number

      Loop->AddLoopTag ( CIFTAG_TYPE_SYMBOL        ); // element symbol
      Loop->AddLoopTag ( CIFTAG_LABEL_ATOM_ID      ); // atom name
      Loop->AddLoopTag ( CIFTAG_LABEL_ALT_ID       ); // alt location
      Loop->AddLoopTag ( CIFTAG_LABEL_COMP_ID      ); // residue name
      Loop->AddLoopTag ( CIFTAG_LABEL_ASYM_ID      ); // chain ID
      Loop->AddLoopTag ( CIFTAG_LABEL_ENTITY_ID    ); // entity ID
      Loop->AddLoopTag ( CIFTAG_LABEL_SEQ_ID       ); // res seq number
      Loop->AddLoopTag ( CIFTAG_PDBX_PDB_INS_CODE  ); // insertion code
      Loop->AddLoopTag ( CIFTAG_SEGMENT_ID         ); // segment ID

      Loop->AddLoopTag ( CIFTAG_CARTN_X            ); // x-coordinate
      Loop->AddLoopTag ( CIFTAG_CARTN_Y            ); // y-coordinate
      Loop->AddLoopTag ( CIFTAG_CARTN_Z            ); // z-coordinate
      Loop->AddLoopTag ( CIFTAG_OCCUPANCY          ); // occupancy
      Loop->AddLoopTag ( CIFTAG_B_ISO_OR_EQUIV     ); // temp factor

      Loop->AddLoopTag ( CIFTAG_CARTN_X_ESD        ); // x-sigma
      Loop->AddLoopTag ( CIFTAG_CARTN_Y_ESD        ); // y-sigma
      Loop->AddLoopTag ( CIFTAG_CARTN_Z_ESD        ); // z-sigma
      Loop->AddLoopTag ( CIFTAG_OCCUPANCY_ESD      ); // occupancy-sigma
      Loop->AddLoopTag ( CIFTAG_B_ISO_OR_EQUIV_ESD ); // t-factor-sigma

      Loop->AddLoopTag ( CIFTAG_PDBX_FORMAL_CHARGE ); // charge on atom

      Loop->AddLoopTag ( CIFTAG_AUTH_SEQ_ID        ); // res seq number
      Loop->AddLoopTag ( CIFTAG_AUTH_COMP_ID       ); // residue name
      Loop->AddLoopTag ( CIFTAG_AUTH_ASYM_ID       ); // chain id
      Loop->AddLoopTag ( CIFTAG_AUTH_ATOM_ID       ); // atom name

      Loop->AddLoopTag ( CIFTAG_PDBX_PDB_MODEL_NUM ); // model number

    }

    if (Ter)  {   // ter record

      if (!(WhatIsSet & ASET_Coordinates))
        return;

      // (0)
      Loop->AddString  ( pstr("TER") );
      // (1)
      if (serNum>0)  Loop->AddInteger ( serNum );
               else  Loop->AddInteger ( index  );
      // (2,3,4)
      Loop->AddNoData ( mmcif::CIF_NODATA_QUESTION );  // no element symbol
      Loop->AddNoData ( mmcif::CIF_NODATA_QUESTION );  // no atom name
      Loop->AddNoData ( mmcif::CIF_NODATA_QUESTION );  // no alt code
      if (residue)  {
        // (5)
        Loop->AddString ( residue->label_comp_id );
        // (6)
        Loop->AddString ( residue->label_asym_id );
        // (7)
        if (residue->label_entity_id>0)
             Loop->AddInteger ( residue->label_entity_id );
        else Loop->AddNoData  ( mmcif::CIF_NODATA_DOT           );
        // (8)
        if (residue->label_seq_id>MinInt4)
             Loop->AddInteger ( residue->label_seq_id );
        else Loop->AddNoData  ( mmcif::CIF_NODATA_DOT        );
        // (9)
        Loop->AddString ( residue->insCode,true );
      } else  {
        // (5,6,7,8,9)
        Loop->AddString ( NULL );
        Loop->AddString ( NULL );
        Loop->AddNoData ( mmcif::CIF_NODATA_DOT );
        Loop->AddNoData ( mmcif::CIF_NODATA_DOT );
        Loop->AddNoData ( mmcif::CIF_NODATA_DOT );
      }

      // (10-21)
      for (i=10;i<=21;i++)
        Loop->AddNoData ( mmcif::CIF_NODATA_QUESTION );

      // (22,23)
      if (residue)  {
        if (residue->seqNum>MinInt4)
             Loop->AddInteger ( residue->seqNum  );
        else Loop->AddNoData  ( mmcif::CIF_NODATA_DOT   );
        Loop->AddString ( residue->name );
      } else  {
        Loop->AddNoData ( mmcif::CIF_NODATA_DOT );
        Loop->AddString ( NULL           );
      }

      // (24)
      if (chain)  Loop->AddString ( chain->chainID,true );
            else  Loop->AddString ( NULL                );

      // (25)
      Loop->AddNoData ( mmcif::CIF_NODATA_QUESTION );  // no atom name

    } else if (WhatIsSet & (ASET_Coordinates | ASET_CoordSigma))  {
      // normal atom record

      if (!WhatIsSet)  return;

      // (0)
      if (Het)  Loop->AddString ( pstr("HETATM") );
          else  Loop->AddString ( pstr("ATOM")   );
      // (1)
      if (serNum>0)  Loop->AddInteger ( serNum );
               else  Loop->AddInteger ( index  );


      if (WhatIsSet & ASET_Coordinates)  {

        // (2)
        strcpy_css ( el,element );
        Loop->AddString ( el,true );
        // (3)
        Loop->AddString ( label_atom_id  );  // assigned atom name
        // (4)
        Loop->AddString  ( altLoc,true );  // alt code

        if (residue)  {
          // (5)
          Loop->AddString ( residue->label_comp_id );
          // (6)
          Loop->AddString ( residue->label_asym_id );
          // (7)
          if (residue->label_entity_id>0)
               Loop->AddInteger ( residue->label_entity_id );
          else Loop->AddNoData  ( mmcif::CIF_NODATA_DOT           );
          // (8)
          if (residue->label_seq_id>MinInt4)
               Loop->AddInteger ( residue->label_seq_id );
          else Loop->AddNoData  ( mmcif::CIF_NODATA_DOT        );
          // (9)
          Loop->AddString ( residue->insCode,true );
        } else  {
          // (5,6,7,8,9)
          Loop->AddString ( NULL );
          Loop->AddString ( NULL );
          Loop->AddNoData ( mmcif::CIF_NODATA_DOT );
          Loop->AddNoData ( mmcif::CIF_NODATA_DOT );
          Loop->AddNoData ( mmcif::CIF_NODATA_DOT );
        }

        // (10)
        Loop->AddString ( segID ,true );
        // (11,12,13)
        Loop->AddReal ( x );
        Loop->AddReal ( y );
        Loop->AddReal ( z );
        // (14)
        if (WhatIsSet & ASET_Occupancy)
              Loop->AddReal   ( occupancy );
        else  Loop->AddNoData ( mmcif::CIF_NODATA_QUESTION );
        // (15)
        if (WhatIsSet & ASET_tempFactor)
              Loop->AddReal   ( tempFactor );
        else  Loop->AddNoData ( mmcif::CIF_NODATA_QUESTION );

        // (16,17,18)
        if (WhatIsSet & ASET_CoordSigma)  {
          Loop->AddReal ( sigX );
          Loop->AddReal ( sigY );
          Loop->AddReal ( sigZ );
        } else  {
          Loop->AddNoData ( mmcif::CIF_NODATA_QUESTION );
          Loop->AddNoData ( mmcif::CIF_NODATA_QUESTION );
          Loop->AddNoData ( mmcif::CIF_NODATA_QUESTION );
        }
        // (19)
        if ((WhatIsSet & ASET_OccSigma) && (WhatIsSet & ASET_Occupancy))
              Loop->AddReal   ( sigOcc  );
        else  Loop->AddNoData ( mmcif::CIF_NODATA_QUESTION );
        // (20)
        if ((WhatIsSet & ASET_tFacSigma) && (WhatIsSet & ASET_tempFactor))
              Loop->AddReal   ( sigTemp );
        else  Loop->AddNoData ( mmcif::CIF_NODATA_QUESTION );

      } else
        for (i=0;i<18;i++)
          Loop->AddNoData ( mmcif::CIF_NODATA_QUESTION );

      // (21)
      if (WhatIsSet & ASET_Charge)  {
        sprintf ( N,"%+2i",mround(charge) );
        Loop->AddString ( N,true );
      } else
        Loop->AddNoData ( mmcif::CIF_NODATA_QUESTION );

      if (residue)  {
        // (22)
        if (residue->seqNum>MinInt4)
             Loop->AddInteger ( residue->seqNum  );
        else Loop->AddNoData  ( mmcif::CIF_NODATA_DOT   );
        // (23)
        Loop->AddString ( residue->name );
      } else  {
        Loop->AddNoData ( mmcif::CIF_NODATA_DOT );
        Loop->AddNoData ( mmcif::CIF_NODATA_DOT );
      }

      // (24)
      if (chain)  Loop->AddString ( chain->chainID,true );
            else  Loop->AddNoData ( mmcif::CIF_NODATA_DOT      );
      // (25)
      strcpy_css      ( AtName,name );
      Loop->AddString ( AtName      );  // atom name

    }

    // (26)
    if (!model)                Loop->AddNoData  ( mmcif::CIF_NODATA_QUESTION );
    else if (model->serNum>0)  Loop->AddInteger ( model->serNum       );
                         else  Loop->AddNoData  ( mmcif::CIF_NODATA_QUESTION );


    if (WhatIsSet & ASET_Anis_tFac)  {

      RC = CIF->AddLoop ( CIFCAT_ATOM_SITE_ANISOTROP,Loop );
      if (RC!=mmcif::CIFRC_Ok)  {
        // the category was (re)created, provide tags
        Loop->AddLoopTag ( CIFTAG_ID      ); // serial number
        Loop->AddLoopTag ( CIFTAG_U11     ); // component u11
        Loop->AddLoopTag ( CIFTAG_U22     ); // component u22
        Loop->AddLoopTag ( CIFTAG_U33     ); // component u33
        Loop->AddLoopTag ( CIFTAG_U12     ); // component u12
        Loop->AddLoopTag ( CIFTAG_U13     ); // component u13
        Loop->AddLoopTag ( CIFTAG_U23     ); // component u23
        Loop->AddLoopTag ( CIFTAG_U11_ESD ); // component u11 sigma
        Loop->AddLoopTag ( CIFTAG_U22_ESD ); // component u22 sigma
        Loop->AddLoopTag ( CIFTAG_U33_ESD ); // component u33 sigma
        Loop->AddLoopTag ( CIFTAG_U12_ESD ); // component u12 sigma
        Loop->AddLoopTag ( CIFTAG_U13_ESD ); // component u13 sigma
        Loop->AddLoopTag ( CIFTAG_U23_ESD ); // component u23 sigma
        for (i=1;i<index;i++)  {
          Loop->AddInteger ( i );
          for (j=0;j<12;j++)
            Loop->AddString ( NULL );
        }
      }

      if (serNum>0)  Loop->AddInteger ( serNum );
               else  Loop->AddInteger ( index  );

      Loop->AddReal ( u11 );
      Loop->AddReal ( u22 );
      Loop->AddReal ( u33 );
      Loop->AddReal ( u12 );
      Loop->AddReal ( u13 );
      Loop->AddReal ( u23 );
      if (WhatIsSet & ASET_Anis_tFSigma)  {
        Loop->AddReal ( su11 );
        Loop->AddReal ( su22 );
        Loop->AddReal ( su33 );
        Loop->AddReal ( su12 );
        Loop->AddReal ( su13 );
        Loop->AddReal ( su23 );
      }

    }

  }

  ERROR_CODE Atom::ConvertPDBATOM ( int ix, cpstr S )  {
  //   Gets data from the PDB ASCII ATOM record.
  //   This function DOES NOT check the "ATOM" keyword and
  // does not decode the chain and residue parameters! These
  // must be treated by calling process, see
  // Chain::ConvertPDBASCII().

    index = ix;

    if (WhatIsSet & ASET_Coordinates)
      return Error_ATOM_AlreadySet;

    if (!(GetReal(x,&(S[30]),8) &&
          GetReal(y,&(S[38]),8) &&
          GetReal(z,&(S[46]),8)))
      return Error_ATOM_Unrecognized;

    WhatIsSet |= ASET_Coordinates;
    Het = false;
    Ter = false;

    if (GetReal(occupancy ,&(S[54]),6))  WhatIsSet |= ASET_Occupancy;
    if (GetReal(tempFactor,&(S[60]),6))  WhatIsSet |= ASET_tempFactor;

    if (WhatIsSet & (ASET_CoordSigma | ASET_Anis_tFac |
                     ASET_Anis_tFSigma))
      // something was already submitted. check complience
      return CheckData ( S );
    else
      // first data submission. just take the data
      GetData ( S );

    return Error_NoError;

  }

  void  Atom::SetAtomName ( int            ix,
                             int            sN,
                             const AtomName aName,
                             const AltLoc   aLoc,
                             const SegID    sID,
                             const Element  eName )  {
    index   = ix;
    serNum  = sN;
    strcpy     ( name         ,aName      );
    strcpy     ( label_atom_id,aName      );
    strcpy_css ( altLoc       ,pstr(aLoc) );
    strcpy_css ( segID        ,pstr(sID)  );
    if (!eName[0])  element[0] = char(0);
    else if (!eName[1])  {
      element[0] = ' ';
      strcpy ( &(element[1]),eName );
    } else
      strcpy   ( element,eName );
    WhatIsSet = 0;
  }

  ERROR_CODE Atom::ConvertPDBSIGATM ( int ix, cpstr S )  {
  //   Gets data from the PDB ASCII SIGATM record.
  //   This function DOES NOT check the "SIGATM" keyword and
  // does not decode the chain and residue parameters! These
  // must be treated by the calling process, see
  // Chain::ConvertPDBASCII().

    index = ix;

    if (WhatIsSet & ASET_CoordSigma)
      return Error_ATOM_AlreadySet;

    if (!(GetReal(sigX,&(S[30]),8) &&
          GetReal(sigY,&(S[38]),8) &&
          GetReal(sigZ,&(S[46]),8)))
      return Error_ATOM_Unrecognized;

    WhatIsSet |= ASET_CoordSigma;

    if (GetReal(sigOcc ,&(S[54]),6))  WhatIsSet |= ASET_OccSigma;
    if (GetReal(sigTemp,&(S[60]),6))  WhatIsSet |= ASET_tFacSigma;

    if (WhatIsSet & (ASET_Coordinates | ASET_Anis_tFac |
                     ASET_Anis_tFSigma))
      // something was already submitted. check complience
      return CheckData ( S );
    else
      // first data submission. just take the data
      GetData ( S );

    return Error_NoError;

  }

  ERROR_CODE Atom::ConvertPDBANISOU ( int ix, cpstr S )  {
  //   Gets data from the PDB ASCII ANISOU record.
  //   This function DOES NOT check the "ANISOU" keyword and
  // does not decode chain and residue parameters! These must
  // be treated by the calling process, see
  // Chain::ConvertPDBASCII().

    index = ix;

    if (WhatIsSet & ASET_Anis_tFac)
      return Error_ATOM_AlreadySet;

    if (!(GetReal(u11,&(S[28]),7) &&
          GetReal(u22,&(S[35]),7) &&
          GetReal(u33,&(S[42]),7) &&
          GetReal(u12,&(S[49]),7) &&
          GetReal(u13,&(S[56]),7) &&
          GetReal(u23,&(S[63]),7)))
      return Error_ATOM_Unrecognized;

    u11 /= 1.0e4;
    u22 /= 1.0e4;
    u33 /= 1.0e4;
    u12 /= 1.0e4;
    u13 /= 1.0e4;
    u23 /= 1.0e4;

    WhatIsSet |= ASET_Anis_tFac;

    if (WhatIsSet & (ASET_Coordinates | ASET_CoordSigma |
                     ASET_Anis_tFSigma))
      // something was already submitted. check complience
      return CheckData ( S );
    else
      // first data submission. just take the data
      GetData ( S );

    return Error_NoError;

  }

  ERROR_CODE Atom::ConvertPDBSIGUIJ ( int ix, cpstr S )  {
  //   Gets data from the PDB ASCII SIGUIJ record.
  //   This function DOES NOT check the "SIGUIJ" keyword and
  // does not decode the chain and residue parameters! These
  // must be treated by the calling process, see
  // Chain::ConvertPDBASCII().

    index = ix;

    if (WhatIsSet & ASET_Anis_tFSigma)
      return Error_ATOM_AlreadySet;

    if (!(GetReal(su11,&(S[28]),7) &&
          GetReal(su22,&(S[35]),7) &&
          GetReal(su33,&(S[42]),7) &&
          GetReal(su12,&(S[49]),7) &&
          GetReal(su13,&(S[56]),7) &&
          GetReal(su23,&(S[63]),7)))
      return Error_ATOM_Unrecognized;

    su11 /= 1.0e4;
    su22 /= 1.0e4;
    su33 /= 1.0e4;
    su12 /= 1.0e4;
    su13 /= 1.0e4;
    su23 /= 1.0e4;

    WhatIsSet |= ASET_Anis_tFSigma;

    if (WhatIsSet & (ASET_Coordinates | ASET_CoordSigma |
                     ASET_Anis_tFac))
      // something was already submitted. check complience
      return CheckData ( S );
    else
      // first data submission. just take the data
      GetData ( S );

    return Error_NoError;

  }

  ERROR_CODE Atom::ConvertPDBTER ( int ix, cpstr S )  {
  //   Gets data from the PDB ASCII TER record.
  //   This function DOES NOT check the "TER" keyword and
  // does not decode the chain and residue parameters! These
  // must be treated by the calling process, see
  // Chain::ConvertPDBASCII().

    index = ix;

    if (((S[6]>='0') && (S[6]<='9')) || (S[6]==' '))  {
      //   Although against strict PDB format, 'TER' is
      // actually allowed not to have a serial number.
      // This negative value implies that the number is
      // not set.
      if (!(GetInteger(serNum,&(S[6]),5)))  serNum = -1;
    } else
      hy36decode ( 5,&(S[6]),5,&serNum );

  //  if (!(GetInteger(serNum,&(S[6]),5)))  serNum = -1;

    if (WhatIsSet & ASET_Coordinates)
      return Error_ATOM_AlreadySet;

    WhatIsSet       |= ASET_Coordinates;
    Het              = false;
    Ter              = true;
    name[0]          = char(0);
    label_atom_id[0] = char(0);
    element[0]       = char(0);

    return Error_NoError;

  }


  int Atom::GetModelNum()  {
    if (residue) {
      if (residue->chain)
        if (residue->chain->model)
          return residue->chain->model->GetSerNum();
    }
    return 0;
  }

  pstr Atom::GetChainID()  {
    if (residue) {
      if (residue->chain)  return residue->chain->chainID;
    }
    return  pstr("");
  }

  pstr Atom::GetLabelAsymID()  {
    if (residue)  return residue->label_asym_id;
            else  return pstr("");
  }

  pstr  Atom::GetResName()  {
    if (residue)  return residue->name;
            else  return pstr("");
  }

  pstr  Atom::GetLabelCompID()  {
    if (residue)  return residue->label_comp_id;
            else  return pstr("");
  }

  int   Atom::GetAASimilarity ( const ResName resName )  {
    if (residue)
          return  mmdb::GetAASimilarity ( pstr(residue->name),
                                          pstr(resName) );
    else  return -3;
  }

  int   Atom::GetAASimilarity ( PAtom A )  {
    if (residue)  {
      if (A->residue)
            return mmdb::GetAASimilarity ( pstr(residue->name),
                                           pstr(A->residue->name) );
      else  return -4;
    } else
      return -3;
  }

  realtype Atom::GetAAHydropathy()  {
    if (residue)
          return  mmdb::GetAAHydropathy ( pstr(residue->name) );
    else  return  MaxReal;
  }

  realtype Atom::GetOccupancy()  {
    if (WhatIsSet & ASET_Occupancy)  return occupancy;
                               else  return 0.0;
  }

  int   Atom::GetSeqNum()  {
    if (residue)  return residue->seqNum;
            else  return ATOM_NoSeqNum;
  }

  int   Atom::GetLabelSeqID()  {
    if (residue)  return residue->label_seq_id;
            else  return ATOM_NoSeqNum;
  }

  int   Atom::GetLabelEntityID()  {
    if (residue)  return residue->label_entity_id;
            else  return -1;
  }

  pstr  Atom::GetInsCode()  {
    if (residue)  return residue->insCode;
            else  return pstr("");
  }

  int   Atom::GetSSEType()  {
  // works only after SSE calculations
    if (residue)  return residue->SSE;
            else  return SSE_None;
  }

  pstr  Atom::GetAtomCharge ( pstr chrg )  {
    if (WhatIsSet & ASET_Charge)  sprintf ( chrg,"%+2i",mround(charge) );
                            else  strcpy  ( chrg,"  " );
    return chrg;
  }

  PResidue Atom::GetResidue()  {
    return residue;
  }

  PChain  Atom::GetChain()  {
    if (residue)  return residue->chain;
            else  return NULL;
  }

  PModel  Atom::GetModel()  {
    if (residue)  {
      if (residue->chain)  return (PModel)residue->chain->model;
    }
    return NULL;
  }

  int  Atom::GetResidueNo()  {
    if (residue)  {
      if (residue->chain)
           return  residue->chain->GetResidueNo (
                            residue->seqNum,residue->insCode );
      else  return -2;
    } else
      return -1;
  }


  void * Atom::GetCoordHierarchy()  {
    if (residue)  return residue->GetCoordHierarchy();
    return NULL;
  }


  void  Atom::GetStat ( realtype   v,
                         realtype & v_min, realtype & v_max,
                         realtype & v_m,   realtype & v_m2 )  {
    if (v<v_min)  v_min = v;
    if (v>v_max)  v_max = v;
    v_m  += v;
    v_m2 += v*v;
  }



  void  Atom::GetChainCalphas ( PPAtom & Calphas, int & nCalphas,
                                 cpstr altLoc )  {
  //   GetChainCalphas(...) is a specialized function for quick
  // access to C-alphas of chain which includes given atom.
  // This function works faster than an equivalent implementation
  // through MMDB's selection procedures.
  //    Parameters:
  //       Calphas   - array to accept pointers on C-alpha atoms
  //                  If Calphas!=NULL, then the function will
  //                  delete and re-allocate it. When the array
  //                  is no longer needed, the application MUST
  //                  delete it:  delete[] Calphas; Deleting
  //                  Calphas does not delete atoms from MMDB.
  //       nCalphas   - integer to accept number of C-alpha atoms
  //                  and the length of Calphas array.
  //       altLoc     - alternative location indicator. By default
  //                  (""), maximum-occupancy locations are taken.
  PChain    chain;
  PPResidue res;
  PPAtom    atom;
  int        nResidues, nAtoms, i,j,k;

    if (Calphas)  {
      delete[] Calphas;
      Calphas = NULL;
    }
    nCalphas = 0;

    if (residue)  chain = residue->chain;
            else  chain = NULL;

    if (chain)  {

      chain->GetResidueTable ( res,nResidues );

      if (nResidues>0)  {

        Calphas = new PAtom[nResidues];

        if ((!altLoc[0]) || (altLoc[0]==' '))  {  // main conformation

          for (i=0;i<nResidues;i++)  {
            nAtoms = res[i]->nAtoms;
            atom   = res[i]->atom;
            for (j=0;j<nAtoms;j++)
              if (!strcmp(atom[j]->name," CA "))  {
                Calphas[nCalphas++] = atom[j];
                break;
              }
          }

        } else  {  // specific conformation

          for (i=0;i<nResidues;i++)  {
            nAtoms = res[i]->nAtoms;
            atom   = res[i]->atom;
            k      = 0;
            for (j=0;j<nAtoms;j++)
              if (!strcmp(atom[j]->name," CA "))  {
                k = 1;
                if (!atom[j]->altLoc[0])  {
                  // take main conformation now as we do not know if
                  // the specific one is in the file
                  Calphas[nCalphas] = atom[j];
                  k = 2;
                } else if (atom[j]->altLoc[0]==altLoc[0])  {
                  // get specific conformation and quit
                  Calphas[nCalphas] = atom[j];
                  k = 2;
                  break;
                }
              } else if (k)
                break;
            if (k==2)  nCalphas++;
          }

        }

      }

    } else if (residue)  {  // check just this atom's residue

      Calphas = new PAtom[1]; // can't be more than 1 C-alpha!

      nAtoms = residue->nAtoms;
      atom   = residue->atom;

      if ((!altLoc[0]) || (altLoc[0]==' '))  {  // main conformation

        for (j=0;j<nAtoms;j++)
          if (!strcmp(atom[j]->name," CA "))  {
            Calphas[nCalphas++] = atom[j];
            break;
          }

      } else  {  // specific conformation

        k = 0;
        for (j=0;j<nAtoms;j++)
          if (!strcmp(atom[j]->name," CA "))  {
            k = 1;
            if (!atom[j]->altLoc[0])  {
              Calphas[nCalphas] = atom[j];
              k = 2;
            } else if (atom[j]->altLoc[0]==altLoc[0])  {
              Calphas[nCalphas] = atom[j];
              k = 2;
              break;
            }
          } else if (k)
            break;
        if (k==2)  nCalphas++;

      }

    }

    if (Calphas && (!nCalphas))  {
      delete[] Calphas;
      Calphas = NULL;
    }

  }

  bool Atom::isMetal()  {
    return  mmdb::isMetal ( element );
  }

  bool Atom::isSolvent()  {
    if (residue)  return  residue->isSolvent();
    return false;
  }

  bool Atom::isInSelection ( int selHnd )  {
  PRoot  manager = (PRoot)GetCoordHierarchy();
  PMask  mask;
    if (manager)  {
      mask = manager->GetSelMask ( selHnd );
      if (mask)  return CheckMask ( mask );
    }
    return false;
  }

  bool Atom::isNTerminus()  {
    if (residue)  return  residue->isNTerminus();
    return false;
  }

  bool Atom::isCTerminus()  {
    if (residue)  return  residue->isCTerminus();
    return false;
  }

  void  Atom::CalAtomStatistics ( RAtomStat AS )  {
  //   AS must be initialized. The function only accumulates
  // the statistics.

    if (!Ter)  {

      AS.nAtoms++;

      if (AS.WhatIsSet & WhatIsSet & ASET_Coordinates)  {
        GetStat ( x,AS.xmin,AS.xmax,AS.xm,AS.xm2 );
        GetStat ( y,AS.ymin,AS.ymax,AS.ym,AS.ym2 );
        GetStat ( z,AS.zmin,AS.zmax,AS.zm,AS.zm2 );
      } else
        AS.WhatIsSet &= ~ASET_Coordinates;

      if (AS.WhatIsSet & WhatIsSet & ASET_Occupancy)
            GetStat(occupancy,AS.occ_min,AS.occ_max,AS.occ_m,AS.occ_m2);
      else  AS.WhatIsSet &= ~ASET_Occupancy;

      if (AS.WhatIsSet & WhatIsSet & ASET_tempFactor)
            GetStat ( tempFactor,AS.tFmin,AS.tFmax,AS.tFm,AS.tFm2 );
      else  AS.WhatIsSet &= ~ASET_tempFactor;

      if (AS.WhatIsSet & WhatIsSet & ASET_Anis_tFac)  {
        GetStat ( u11,AS.u11_min,AS.u11_max,AS.u11_m,AS.u11_m2 );
        GetStat ( u22,AS.u22_min,AS.u22_max,AS.u22_m,AS.u22_m2 );
        GetStat ( u33,AS.u33_min,AS.u33_max,AS.u33_m,AS.u33_m2 );
        GetStat ( u12,AS.u12_min,AS.u12_max,AS.u12_m,AS.u12_m2 );
        GetStat ( u13,AS.u13_min,AS.u13_max,AS.u13_m,AS.u13_m2 );
        GetStat ( u23,AS.u23_min,AS.u23_max,AS.u23_m,AS.u23_m2 );
      } else
        AS.WhatIsSet &= ~ASET_Anis_tFac;

    }

  }


  realtype Atom::GetDist2 ( PAtom a )  {
  realtype dx,dy,dz;
    dx = a->x - x;
    dy = a->y - y;
    dz = a->z - z;
    return  dx*dx + dy*dy + dz*dz;
  }

  realtype Atom::GetDist2 ( PAtom a, mat44 & tm )  {
  realtype dx,dy,dz;
    dx = tm[0][0]*a->x + tm[0][1]*a->y + tm[0][2]*a->z + tm[0][3] - x;
    dy = tm[1][0]*a->x + tm[1][1]*a->y + tm[1][2]*a->z + tm[1][3] - y;
    dz = tm[2][0]*a->x + tm[2][1]*a->y + tm[2][2]*a->z + tm[2][3] - z;
    return  dx*dx + dy*dy + dz*dz;
  }

  realtype Atom::GetDist2 ( PAtom a, mat33 & r, vect3 & t )  {
  realtype dx,dy,dz;
    dx = r[0][0]*a->x + r[0][1]*a->y + r[0][2]*a->z + t[0] - x;
    dy = r[1][0]*a->x + r[1][1]*a->y + r[1][2]*a->z + t[1] - y;
    dz = r[2][0]*a->x + r[2][1]*a->y + r[2][2]*a->z + t[2] - z;
    return  dx*dx + dy*dy + dz*dz;
  }

  realtype Atom::GetDist2 ( realtype ax, realtype ay, realtype az )  {
  realtype dx,dy,dz;
    dx = ax - x;
    dy = ay - y;
    dz = az - z;
    return  dx*dx + dy*dy + dz*dz;
  }

  realtype Atom::GetCosine ( PAtom a1, PAtom a2 )  {
  // Calculates cosing of angle a1-this-a2, i.e. that between
  // bond [a1,this] and [this,a2].
  realtype dx1,dy1,dz1, dx2,dy2,dz2,r;

    dx1 = a1->x - x;
    dy1 = a1->y - y;
    dz1 = a1->z - z;
    r   = dx1*dx1 + dy1*dy1 + dz1*dz1;

    dx2 = a2->x - x;
    dy2 = a2->y - y;
    dz2 = a2->z - z;
    r  *= dx2*dx2 + dy2*dy2 + dz2*dz2;

    if (r>0.0)  return (dx1*dx2 + dy1*dy2 + dz1*dz2)/sqrt(r);
          else  return 0.0;

  }


  void  Atom::MakeTer()  {
    WhatIsSet |= ASET_Coordinates;
    Het        = false;
    Ter        = true;
  }


  void  Atom::SetAtomName ( const AtomName atomName )  {
    strcpy ( name,atomName );
  }


  void  Atom::SetElementName ( const Element elName )  {
    strcpy ( element,elName );
    if (!element[0])  strcpy ( element,"  " );
    else if ((!element[1]) || (element[1]==' '))  {
      element[2] = char(0);
      element[1] = element[0];
      element[0] = ' ';
    }
  }

  void  Atom::SetCharge ( cpstr chrg )  {
  pstr p;
    charge = strtod ( chrg,&p );
    if (p!=chrg)  {
      WhatIsSet |= ASET_Charge;
      if ((charge>0.0) && (*p=='-'))
        charge = -charge;
    }
  }

  void  Atom::SetCharge ( realtype chrg )  {
    if (chrg<MaxReal)  {
      charge = chrg;
      WhatIsSet |= ASET_Charge;
    }
  }

  void  Atom::SetAtomIndex ( int ix )  {
  // don't use in your applications!
    index = ix;
  }

  pstr  Atom::GetAtomID ( pstr AtomID )  {
  char  S[50];
    AtomID[0] = char(0);
    if (residue)  {
      if (residue->chain)  {
        if (residue->chain->model)
              sprintf (AtomID,"/%i/",residue->chain->model->GetSerNum());
        else  strcpy  ( AtomID,"/-/" );
        strcat ( AtomID,residue->chain->chainID );
      } else
        strcpy ( AtomID,"/-/-" );
      ParamStr ( AtomID,pstr("/"),residue->seqNum );
      if (residue->name[0])  {
        strcat ( AtomID,"(" );
        strcat ( AtomID,residue->name );
        strcat ( AtomID,")" );
      }
      if (residue->insCode[0])  {
        strcat ( AtomID,"." );
        strcat ( AtomID,residue->insCode );
      }
      strcat ( AtomID,"/" );
    } else
      strcpy ( AtomID,"/-/-/-/" );
    strcpy_css ( S,name );
    if (!S[0])  strcpy ( S,"-" );
    strcat     ( AtomID,S );
    strcpy_css ( S,element );
    if (S[0])  {
      strcat ( AtomID,"[" );
      strcat ( AtomID,S   );
      strcat ( AtomID,"]" );
    }
    if (altLoc[0])  {
      strcat ( AtomID,":" );
      strcat ( AtomID,altLoc );
    }
    return AtomID;
  }

  pstr  Atom::GetAtomIDfmt ( pstr AtomID )  {
  int  n;
  char S[50];
    AtomID[0] = char(0);
    if (residue)  {
      if (residue->chain)  {
        if (residue->chain->model)  {
          n = residue->chain->model->GetNumberOfModels();
      if      (n<10)   strcpy ( S,"/%1i/" );
      else if (n<100)  strcpy ( S,"/%2i/" );
      else if (n<1000) strcpy ( S,"/%3i/" );
                      else strcpy ( S,"/%i/"  );
          sprintf ( AtomID,S,residue->chain->model->GetSerNum() );
        } else
          strcpy  ( AtomID,"/-/" );
        strcat ( AtomID,residue->chain->chainID );
      } else
        strcpy ( AtomID,"/-/-" );
      if ((-999<=residue->seqNum) && (residue->seqNum<=9999))
            sprintf ( S,"/%4i",residue->seqNum );
      else  sprintf ( S,"/%i" ,residue->seqNum );
      strcat  ( AtomID,S );
      sprintf ( S,"(%3s).%1s/",residue->name,residue->insCode );
      strcat  ( AtomID,S );
    } else
      strcpy ( AtomID,"/-/-/----(---).-/" );
    sprintf ( S,"%4s[%2s]:%1s",name,element,altLoc );
    strcat  ( AtomID,S );
    return AtomID;
  }



  ERROR_CODE Atom::ConvertPDBHETATM ( int ix, cpstr S )  {
  //   Gets data from the PDB ASCII HETATM record.
  //   This function DOES NOT check the "HETATM" keyword and
  // does not decode the chain and residue parameters! These
  // must be treated by the calling process, see
  // Chain::ConvertPDBASCII().
  ERROR_CODE RC;
    RC  = ConvertPDBATOM ( ix,S );
    Het = true;
    return RC;
  }

  void Atom::GetData ( cpstr S )  {
  pstr p;

    if (((S[6]>='0') && (S[6]<='9')) || (S[6]==' '))  {
      //   Here we forgive cards with unreadable serial numbers
      // as we always have index (ix) for the card. For the sake
      // of strict PDB syntax we would have to return
      // Error_UnrecognizedInteger here.
      if (!(GetInteger(serNum,&(S[6]),5)))  serNum = -1;
    } else
      hy36decode ( 5,&(S[6]),5,&serNum );

  //  if (!(GetInteger(serNum,&(S[6]),5)))  serNum = index;

    altLoc[0] = S[16];
    if (altLoc[0]==' ')  altLoc[0] = char(0);
                   else  altLoc[1] = char(0);
    GetString   ( name   ,&(S[12]),4 );
    strcpy_ncss ( segID  ,&(S[72]),4 );
    GetString   ( element,&(S[76]),2 );
    charge = strtod ( &(S[78]),&p );
    if ((charge!=0.0) && (p!=&(S[78])))  {
      WhatIsSet |= ASET_Charge;
      if ((charge>0.0) && (*p=='-'))
        charge = -charge;
    }

    RestoreElementName();
    strcpy ( label_atom_id,name );

  }

  ERROR_CODE Atom::CheckData ( cpstr S )  {
  int      sN;
  AltLoc   aloc;
  SegID    sID;
  Element  elmnt;
  pstr     p;
  realtype achrg;

    aloc[0] = S[16];
    if (aloc[0]==' ')  aloc[0] = char(0);
                 else  aloc[1] = char(0);

    strcpy_ncss ( sID  ,&(S[72]),4 );
    GetString   ( elmnt,&(S[76]),2 );

    if (ignoreCharge)
      achrg = charge;
    else  {
      achrg = strtod ( &(S[78]),&p );
      if ((achrg!=0.0) && (p!=&(S[78])))  {
        if ((achrg>0.0) && (*p=='-'))
          achrg = -achrg;
      }
    }

  //  if (!(GetInteger(sN,&(S[6]),5)))
  //    sN = index;

    if (hy36decode(5,&(S[6]),5,&sN))
      sN = index;

    if (ignoreSegID)  {
      if (segID[0])  strcpy ( sID,segID );
               else  strcpy ( segID,sID );
    }

    if (ignoreElement)  {
      if (element[0])  strcpy ( elmnt,element );
                 else  strcpy ( element,elmnt );
    }

    if (ignoreUnmatch)  return Error_NoError;

    //   Here we forgive cards with unreadable serial numbers
    // as we always have index (ix) for the card. For the sake
    // of strict PDB syntax we would have to return
    // Error_UnrecognizedInteger .
    if ((sN!=serNum)                  ||
        (strcmp (altLoc ,aloc      )) ||
        (strncmp(name   ,&(S[12]),4)) ||
        (strcmp (segID  ,sID       )) ||
        (strcmp (element,elmnt     )) ||
        (charge!=achrg))  {
      /*
  char name1[100];
  strncpy ( name1,&(S[12]),4 );  name1[4] = char(0);
      printf ( "\n  serNum   %5i  %5i\n"
               "  residue  '%s' '%s'\n"
               "  altLoc   '%s' '%s'\n"
               "  name     '%s' '%s'\n"
               "  segId    '%s' '%s'\n"
               "  element  '%s' '%s'\n"
               "  charge   '%s' '%s'\n",
               sN,serNum, res->name,residue->name,
               altLoc ,aloc,  name,name1,
           segID  ,sID,
        element,elmnt,
           charge ,achrg );
      if (res!=residue)  printf (" it's a residue\n" );
      */
      return Error_ATOM_Unmatch;
    }

    return Error_NoError;

  }


  ERROR_CODE Atom::GetCIF ( int ix, mmcif::PLoop Loop,
                            mmcif::PLoop LoopAnis )  {
  char        PDBGroup[30];
  int         k;
  ERROR_CODE  RC;

    index = ix;

    if (WhatIsSet & ASET_Coordinates)
      return Error_ATOM_AlreadySet;

  /*

  loop_
  *0  _atom_site.group_PDB
  *1  _atom_site.id
  *2  _atom_site.type_symbol         <- chem elem
  -3  _atom_site.label_atom_id       <- atom name
  *4  _atom_site.label_alt_id        <- alt code
  =5  _atom_site.label_comp_id       <- res name ???
  =6  _atom_site.label_asym_id       <- chain id ???
  =7  _atom_site.label_entity_id     < ???
  =8  _atom_site.label_seq_id        <- poly seq id
  +9  _atom_site.pdbx_PDB_ins_code   <- ins code
  -10 _atom_site.segment_id          <- segment id
  *11 _atom_site.Cartn_x
  *12 _atom_site.Cartn_y
  *13 _atom_site.Cartn_z
  *14 _atom_site.occupancy
  *15 _atom_site.B_iso_or_equiv
  *16 _atom_site.Cartn_x_esd
  *17 _atom_site.Cartn_y_esd
  *18 _atom_site.Cartn_z_esd
  *19 _atom_site.occupancy_esd
  *20 _atom_site.B_iso_or_equiv_esd
  *21 _atom_site.pdbx_formal_charge
  +22 _atom_site.auth_seq_id          <- seq id we want
  +23 _atom_site.auth_comp_id         <- res name we want
  +24 _atom_site.auth_asym_id         <- ch id we want ?
  *25 _atom_site.auth_atom_id         <- atom name we want ?
  +26 _atom_site.pdbx_PDB_model_num   <- model no

  '+' read in Root::CheckAtomPlace()
  '=' new in residue, read in Root::CheckAtomPlace()
  '-' new in atom

  */


    // (0)
    k = ix-1;
    CIFGetString ( PDBGroup,Loop,CIFTAG_GROUP_PDB,k,
                   sizeof(PDBGroup),pstr("") );

    Ter = !strcmp(PDBGroup,pstr("TER")   );
    Het = !strcmp(PDBGroup,pstr("HETATM"));

    // (1)
    RC = CIFGetInteger1 ( serNum,Loop,CIFTAG_ID,k );
    if (RC)  {
      if (Ter)                    serNum = -1;
      else if (RC==Error_NoData)  serNum = index;
      else
        return RC;
    }

    if (Ter)  {
      Loop->DeleteRow ( k );
      WhatIsSet |= ASET_Coordinates;
      return Error_NoError;
    }

    // (25)
    CIFGetString ( name,Loop,CIFTAG_AUTH_ATOM_ID,k,
                          sizeof(name)  ,pstr("") );
    // (3)
    CIFGetString ( label_atom_id,Loop,CIFTAG_LABEL_ATOM_ID,k,
                          sizeof(label_atom_id),pstr("") );
    if (!name[0])
      strcpy ( name,label_atom_id );
    // (4)
    CIFGetString ( altLoc,Loop,CIFTAG_LABEL_ALT_ID ,k,
                          sizeof(altLoc),pstr("") );

    // (11,12,13)
    RC = CIFGetReal1 ( x,Loop,CIFTAG_CARTN_X,k );
    if (!RC) RC = CIFGetReal1 ( y,Loop,CIFTAG_CARTN_Y,k );
    if (!RC) RC = CIFGetReal1 ( z,Loop,CIFTAG_CARTN_Z,k );
    if (RC)  return Error_ATOM_Unrecognized;
    WhatIsSet |= ASET_Coordinates;

    // (14)
    if (!CIFGetReal1(occupancy,Loop,CIFTAG_OCCUPANCY,k))
      WhatIsSet |= ASET_Occupancy;
    // (15)
    if (!CIFGetReal1(tempFactor,Loop,CIFTAG_B_ISO_OR_EQUIV,k))
      WhatIsSet |= ASET_tempFactor;

    // (10)
    CIFGetString ( segID,Loop,CIFTAG_SEGMENT_ID,k,
                         sizeof(segID) ,pstr("") );
    // (21)
    if (!CIFGetReal1(charge,Loop,CIFTAG_PDBX_FORMAL_CHARGE,k))
      WhatIsSet |= ASET_Charge;
    // (2)
    RC = CIFGetString ( element,Loop,CIFTAG_TYPE_SYMBOL,k,
                                sizeof(element),pstr("") );
    if (RC)
      CIFGetString ( element,Loop,CIFTAG_ATOM_TYPE_SYMBOL,k,
                          sizeof(element),pstr("") );

    RestoreElementName();
    MakePDBAtomName();

    // (16,17,18)
    RC = CIFGetReal1 ( sigX,Loop,CIFTAG_CARTN_X_ESD,k );
    if (!RC) RC = CIFGetReal1 ( sigY,Loop,CIFTAG_CARTN_Y_ESD,k );
    if (!RC) RC = CIFGetReal1 ( sigZ,Loop,CIFTAG_CARTN_Z_ESD,k );
    if (RC==Error_UnrecognizedReal)
      return RC;
    if (!RC) WhatIsSet |= ASET_CoordSigma;

    // (19)
    if (!CIFGetReal1(sigOcc,Loop,CIFTAG_OCCUPANCY_ESD,k))
      WhatIsSet |= ASET_OccSigma;
    // (20)
    if (!CIFGetReal1(sigTemp,Loop,CIFTAG_B_ISO_OR_EQUIV_ESD,k))
      WhatIsSet |= ASET_tFacSigma;

    Loop->DeleteRow ( k );

    if (LoopAnis)  {

      RC = CIFGetReal1 ( u11,LoopAnis,CIFTAG_U11,k );
      if (!RC) RC = CIFGetReal1 ( u22,LoopAnis,CIFTAG_U22,k );
      if (!RC) RC = CIFGetReal1 ( u33,LoopAnis,CIFTAG_U33,k );
      if (!RC) RC = CIFGetReal1 ( u13,LoopAnis,CIFTAG_U13,k );
      if (!RC) RC = CIFGetReal1 ( u12,LoopAnis,CIFTAG_U12,k );
      if (!RC) RC = CIFGetReal1 ( u23,LoopAnis,CIFTAG_U23,k );
      if (RC==Error_UnrecognizedReal)
        return RC;
      if (!RC) WhatIsSet |= ASET_Anis_tFac;

      RC = CIFGetReal1 ( su11,LoopAnis,CIFTAG_U11_ESD,k );
      if (!RC) RC = CIFGetReal1 ( su22,LoopAnis,CIFTAG_U22_ESD,k );
      if (!RC) RC = CIFGetReal1 ( su33,LoopAnis,CIFTAG_U33_ESD,k );
      if (!RC) RC = CIFGetReal1 ( su13,LoopAnis,CIFTAG_U13_ESD,k );
      if (!RC) RC = CIFGetReal1 ( su12,LoopAnis,CIFTAG_U12_ESD,k );
      if (!RC) RC = CIFGetReal1 ( su23,LoopAnis,CIFTAG_U23_ESD,k );
      if (RC==Error_UnrecognizedReal)
        return RC;
      if (!RC) WhatIsSet |= ASET_Anis_tFSigma;

      LoopAnis->DeleteRow ( k );

    }

    return Error_NoError;

  }

  bool Atom::RestoreElementName()  {
  //  This function works only if element name is not given.

    if (Ter)  {
      name[0]    = char(0);
      element[0] = char(0);
      return false;
    }
    if ((!element[0]) ||
        ((element[0]==' ') && ((!element[1]) || (element[1]==' '))))  {
      if (strlen(name)==4)  {
        if ((name[0]>='A') && (name[0]<='Z'))  {
          element[0] = name[0];
          element[1] = name[1];
        } else  {
          element[0] = ' ';
          element[1] = name[1];
        }
      } else  {  // nasty hack for mmcif files without element column
        element[0] = ' ';
        element[1] = name[0];
      }
      element[2] = char(0);
      return false;
    } else if (!element[1])  {
      // not aligned element name, possibly coming from mmCIF
      element[1] = element[0];
      element[0] = ' ';
      element[2] = char(0);
      return false;
    }
    return true;
  }

  bool Atom::MakePDBAtomName()  {
  int     i,k;

    if (Ter)  {
      name   [0] = char(0);
      element[0] = char(0);
      return false;
    }
    UpperCase ( name    );
    UpperCase ( element );
    if ((element[0]==' ') && (element[1]==' '))  {
      // element name not given, make one from the atom name
      if ((name[0]>='A') && (name[0]<='Z'))  {
        if (!name[1])  {
          name[4] = char(0);
          name[3] = ' ';
          name[2] = ' ';
          name[1] = name[0];
          name[0] = ' ';
        }
        /* the commented part looks like a wrong inheritance
           from FORTRAN RWBrook. Commented on 04.03.2004,
           to be removed.
        else if ((name[0]=='C') && (name[1]=='A'))  {
          name[4] = char(0);
          name[3] = name[2];
          name[2] = name[1];
          name[1] = name[0];
          name[0] = ' ';
        }
        */
        element[0] = name[0];
        element[1] = name[1];
      } else  {
        element[0] = ' ';
        element[1] = name[1];
      }
      element[2] = char(0);
      return false;
    } else if ((name[0]>='A') && (name[0]<='Z'))  {
      if (!element[1])  {
        element[2] = char(0);
        element[1] = element[0];
        element[0] = ' ';
        k = strlen(name);
        if (k<4)  {
          for (i=3;i>0;i--)
            name[i] = name[i-1];
          name[0] = ' ';
          k++;
          while (k<4)
            name[k++] = ' ';
          name[k] = char(0);
        }
      } else if ((element[0]==' ') && (element[1]!=name[1]))  {
        for (i=3;i>0;i--)
          name[i] = name[i-1];
        name[0] = ' ';
        name[4] = char(0);
        k = strlen(name);
        while (k<4)
          name[k++] = ' ';
        name[k] = char(0);
      } else  {
        k = strlen(name);
        while (k<4)
          name[k++] = ' ';
        name[k] = char(0);
      }
    }
    return true;
  }

  void  Atom::SetCoordinates ( realtype xx,  realtype yy, realtype zz,
                               realtype occ, realtype tFac )  {
    x = xx;
    y = yy;
    z = zz;
    occupancy  = occ;
    tempFactor = tFac;
    WhatIsSet |= ASET_Coordinates | ASET_Occupancy | ASET_tempFactor;
  }

  void  Atom::Transform ( mat33 & tm, vect3 & v ) {
  realtype  x1,y1,z1;
    x1 = tm[0][0]*x + tm[0][1]*y + tm[0][2]*z + v[0];
    y1 = tm[1][0]*x + tm[1][1]*y + tm[1][2]*z + v[1];
    z1 = tm[2][0]*x + tm[2][1]*y + tm[2][2]*z + v[2];
    x = x1;
    y = y1;
    z = z1;
  }

  void  Atom::Transform ( mat44 & tm ) {
  realtype  x1,y1,z1;
    x1 = tm[0][0]*x + tm[0][1]*y + tm[0][2]*z + tm[0][3];
    y1 = tm[1][0]*x + tm[1][1]*y + tm[1][2]*z + tm[1][3];
    z1 = tm[2][0]*x + tm[2][1]*y + tm[2][2]*z + tm[2][3];
    x = x1;
    y = y1;
    z = z1;
  }

  void  Atom::TransformCopy ( mat44    & tm,
                               realtype & xx,
                               realtype & yy,
                               realtype & zz )  {
    xx = tm[0][0]*x + tm[0][1]*y + tm[0][2]*z + tm[0][3];
    yy = tm[1][0]*x + tm[1][1]*y + tm[1][2]*z + tm[1][3];
    zz = tm[2][0]*x + tm[2][1]*y + tm[2][2]*z + tm[2][3];
  }

  void  Atom::TransformSet ( mat44  & tm,
                              realtype xx,
                              realtype yy,
                              realtype zz ) {
    x = tm[0][0]*xx + tm[0][1]*yy + tm[0][2]*zz + tm[0][3];
    y = tm[1][0]*xx + tm[1][1]*yy + tm[1][2]*zz + tm[1][3];
    z = tm[2][0]*xx + tm[2][1]*yy + tm[2][2]*zz + tm[2][3];
  }


  // -------  user-defined data handlers

  int  Atom::PutUDData ( int UDDhandle, int iudd )  {
    if (UDDhandle & UDRF_ATOM)
          return  UDData::putUDData ( UDDhandle,iudd );
    else  return  UDDATA_WrongUDRType;
  }

  int  Atom::PutUDData ( int UDDhandle, realtype rudd )  {
    if (UDDhandle & UDRF_ATOM)
          return  UDData::putUDData ( UDDhandle,rudd );
    else  return  UDDATA_WrongUDRType;
  }

  int  Atom::PutUDData ( int UDDhandle, cpstr sudd )  {
    if (UDDhandle & UDRF_ATOM)
          return  UDData::putUDData ( UDDhandle,sudd );
    else  return  UDDATA_WrongUDRType;
  }

  int  Atom::GetUDData ( int UDDhandle, int & iudd )  {
    if (UDDhandle & UDRF_ATOM)
          return  UDData::getUDData ( UDDhandle,iudd );
    else  return  UDDATA_WrongUDRType;
  }

  int  Atom::GetUDData ( int UDDhandle, realtype & rudd )  {
    if (UDDhandle & UDRF_ATOM)
          return  UDData::getUDData ( UDDhandle,rudd );
    else  return  UDDATA_WrongUDRType;
  }

  int  Atom::GetUDData ( int UDDhandle, pstr sudd, int maxLen )  {
    if (UDDhandle & UDRF_ATOM)
          return  UDData::getUDData ( UDDhandle,sudd,maxLen );
    else  return  UDDATA_WrongUDRType;
  }

  int  Atom::GetUDData ( int UDDhandle, pstr & sudd )  {
    if (UDDhandle & UDRF_ATOM)
          return  UDData::getUDData ( UDDhandle,sudd );
    else  return  UDDATA_WrongUDRType;
  }


  void  Atom::Copy ( PAtom atom )  {
  // this does not make any references in residues and does
  // not change indices!! it does change serial numbers, though.

    serNum     = atom->serNum;
    x          = atom->x;
    y          = atom->y;
    z          = atom->z;
    occupancy  = atom->occupancy;
    tempFactor = atom->tempFactor;
    sigX       = atom->sigX;
    sigY       = atom->sigY;
    sigZ       = atom->sigZ;
    sigOcc     = atom->sigOcc;
    sigTemp    = atom->sigTemp;
    u11        = atom->u11;
    u22        = atom->u22;
    u33        = atom->u33;
    u12        = atom->u12;
    u13        = atom->u13;
    u23        = atom->u23;
    su11       = atom->su11;
    su22       = atom->su22;
    su33       = atom->su33;
    su12       = atom->su12;
    su13       = atom->su13;
    su23       = atom->su23;
    Het        = atom->Het;
    Ter        = atom->Ter;
    WhatIsSet  = atom->WhatIsSet;

    strcpy ( name         ,atom->name          );
    strcpy ( label_atom_id,atom->label_atom_id );
    strcpy ( altLoc       ,atom->altLoc        );
    strcpy ( segID        ,atom->segID         );
    strcpy ( element      ,atom->element       );
    strcpy ( energyType   ,atom->energyType    );
    charge = atom->charge;

  }

  int Atom::CheckID ( const AtomName aname, const Element elname,
                       const AltLoc aloc )  {
  pstr p1,p2;
    if (aname)  {
      if (aname[0]!='*')  {
        p1 = name;
        while (*p1==' ') p1++;
        p2 = pstr(aname);
        while (*p2==' ') p2++;
        while ((*p2) && (*p1) && (*p1!=' ') && (*p2!=' '))  {
          if (*p1!=*p2)  return 0;
          p1++;
          p2++;
        }
        if (*p1!=*p2)  {
          if (((*p1) && (*p1!=' ')) ||
              ((*p2) && (*p2!=' ')))  return 0;
        }
      }
    }
    if (elname)  {
      if (elname[0]!='*')  {
        p1 = element;
        while (*p1==' ')  p1++;
        p2 = pstr(elname);
        while (*p2==' ')  p2++;
        while ((*p2) && (*p1) && (*p1!=' ') && (*p2!=' '))  {
          if (*p1!=*p2)  return 0;
          p1++;
          p2++;
        }
        if (*p1!=*p2)  return 0;
      }
    }
    if (aloc)  {
      if ((aloc[0]!='*') && (strcmp(aloc,altLoc)))   return 0;
    }
    return 1;
  }

  int Atom::CheckIDS ( cpstr ID )  {
  AtomName aname;
  Element  elname;
  AltLoc   aloc;
  pstr     p;
    p = strrchr ( ID,'/' );
    if (p)  p++;
      else  p = pstr(ID);
    ParseAtomID ( p,aname,elname,aloc );
    return  CheckID ( aname,elname,aloc );
  }

  void  Atom::SetShortBinary()  {
    WhatIsSet |= ASET_ShortBinary;
  }

  void  Atom::write ( io::RFile f )  {
  int  i,k;
  byte Version=2;
  byte nb;

    f.WriteWord ( &WhatIsSet );
    if (WhatIsSet & ASET_ShortBinary)  {
      if (Ter)  WhatIsSet |= ASET_ShortTer;
      if (Het)  WhatIsSet |= ASET_ShortHet;
      f.WriteInt     ( &index        );
      f.WriteTerLine ( name   ,false );
      f.WriteTerLine ( altLoc ,false );
      f.WriteTerLine ( element,false );
      if (WhatIsSet & ASET_Coordinates)  {
        f.WriteFloat ( &x );
        f.WriteFloat ( &y );
        f.WriteFloat ( &z );
      }
      return;
    }

    f.WriteByte  ( &Version );

    UDData::write ( f );

    f.WriteInt     ( &serNum );
    f.WriteInt     ( &index  );
    f.WriteTerLine ( name         ,false );
    f.WriteTerLine ( label_atom_id,false );
    f.WriteTerLine ( altLoc       ,false );
    f.WriteTerLine ( segID        ,false );
    f.WriteTerLine ( element      ,false );
    f.WriteTerLine ( energyType   ,false );
    f.WriteFloat   ( &charge );
    f.WriteBool    ( &Het    );
    f.WriteBool    ( &Ter    );

    if (WhatIsSet & ASET_Coordinates)  {
      f.WriteFloat ( &x );
      f.WriteFloat ( &y );
      f.WriteFloat ( &z );
      if (WhatIsSet & ASET_Occupancy)
        f.WriteFloat ( &occupancy  );
      if (WhatIsSet & ASET_tempFactor)
        f.WriteFloat ( &tempFactor );
    }

    if (WhatIsSet & ASET_CoordSigma)  {
      f.WriteFloat ( &sigX );
      f.WriteFloat ( &sigY );
      f.WriteFloat ( &sigZ );
      if ((WhatIsSet & ASET_Occupancy) &&
          (WhatIsSet & ASET_OccSigma))
        f.WriteFloat ( &sigOcc );
      if ((WhatIsSet & ASET_tempFactor) &&
          (WhatIsSet & ASET_tFacSigma))
        f.WriteFloat ( &sigTemp );
    }

    if (WhatIsSet & ASET_Anis_tFac)  {
      f.WriteFloat ( &u11 );
      f.WriteFloat ( &u22 );
      f.WriteFloat ( &u33 );
      f.WriteFloat ( &u12 );
      f.WriteFloat ( &u13 );
      f.WriteFloat ( &u23 );
      if (WhatIsSet & ASET_Anis_tFSigma)  {
        f.WriteFloat ( &su11 );
        f.WriteFloat ( &su22 );
        f.WriteFloat ( &su33 );
        f.WriteFloat ( &su12 );
        f.WriteFloat ( &su13 );
        f.WriteFloat ( &su23 );
      }
    }

    nb = byte(nBonds & 0x000000FF);
    f.WriteByte ( &nb );
    for (i=0;i<nb;i++)
      if (Bond[i].atom)  {
        f.WriteInt  ( &(Bond[i].atom->index) );
        f.WriteByte ( &(Bond[i].order)       );
      } else  {
        k = -1;
        f.WriteInt  ( &k );
      }

  }

  void  Atom::read ( io::RFile f ) {
  int  i,k;
  byte nb,Version;

    FreeMemory();

    f.ReadWord ( &WhatIsSet );
    if (WhatIsSet & ASET_ShortBinary)  {
      f.ReadInt     ( &index        );
      f.ReadTerLine ( name   ,false );
      f.ReadTerLine ( altLoc ,false );
      f.ReadTerLine ( element,false );
      if (WhatIsSet & ASET_Coordinates)  {
        f.ReadFloat ( &x );
        f.ReadFloat ( &y );
        f.ReadFloat ( &z );
      }
      serNum     = index;
      Ter        = WhatIsSet & ASET_ShortTer;
      Het        = WhatIsSet & ASET_ShortHet;
      name   [4] = char(0);
      altLoc [1] = char(0);
      element[2] = char(0);
      segID  [0] = char(0);
      charge     = 0.0;
      WhatIsSet &= ASET_All;
      return;
    }

    f.ReadByte  ( &Version );

    UDData::read ( f );

    f.ReadInt     ( &serNum );
    f.ReadInt     ( &index  );
    f.ReadTerLine ( name      ,false );
    if (Version>1)
      f.ReadTerLine ( label_atom_id,false );
    f.ReadTerLine ( altLoc    ,false );
    f.ReadTerLine ( segID     ,false );
    f.ReadTerLine ( element   ,false );
    f.ReadTerLine ( energyType,false );
    f.ReadFloat   ( &charge );
    f.ReadBool    ( &Het    );
    f.ReadBool    ( &Ter    );

    if (WhatIsSet & ASET_Coordinates)  {
      f.ReadFloat ( &x );
      f.ReadFloat ( &y );
      f.ReadFloat ( &z );
      if (WhatIsSet & ASET_Occupancy)  f.ReadFloat ( &occupancy  );
                                 else  occupancy = 0.0;
      if (WhatIsSet & ASET_tempFactor) f.ReadFloat ( &tempFactor );
                                 else  tempFactor = 0.0;
    } else  {
      x          = 0.0;
      y          = 0.0;
      z          = 0.0;
      occupancy  = 0.0;
      tempFactor = 0.0;
    }

    if (WhatIsSet & ASET_CoordSigma)  {
      f.ReadFloat ( &sigX );
      f.ReadFloat ( &sigY );
      f.ReadFloat ( &sigZ );
      if ((WhatIsSet & ASET_Occupancy) &&
          (WhatIsSet & ASET_OccSigma))
            f.ReadFloat ( &sigOcc );
      else  sigOcc = 0.0;
      if ((WhatIsSet & ASET_tempFactor) &&
          (WhatIsSet & ASET_tFacSigma))
            f.ReadFloat ( &sigTemp );
      else  sigTemp = 0.0;
    } else  {
      sigX    = 0.0;
      sigY    = 0.0;
      sigZ    = 0.0;
      sigOcc  = 0.0;
      sigTemp = 0.0;
    }

    if (WhatIsSet & ASET_Anis_tFac)  {
      f.ReadFloat ( &u11 );
      f.ReadFloat ( &u22 );
      f.ReadFloat ( &u33 );
      f.ReadFloat ( &u12 );
      f.ReadFloat ( &u13 );
      f.ReadFloat ( &u23 );
      if (WhatIsSet & ASET_Anis_tFSigma)  {
        f.ReadFloat ( &su11 );
        f.ReadFloat ( &su22 );
        f.ReadFloat ( &su33 );
        f.ReadFloat ( &su12 );
        f.ReadFloat ( &su13 );
        f.ReadFloat ( &su23 );
      } else  {
        su11 = 0.0;
        su22 = 0.0;
        su33 = 0.0;
        su12 = 0.0;
        su13 = 0.0;
        su23 = 0.0;
      }
    } else  {
      u11  = 0.0;
      u22  = 0.0;
      u33  = 0.0;
      u12  = 0.0;
      u13  = 0.0;
      u23  = 0.0;
      su11 = 0.0;
      su22 = 0.0;
      su33 = 0.0;
      su12 = 0.0;
      su13 = 0.0;
      su23 = 0.0;
    }

    f.ReadByte ( &nb );
    if (nb>0)  {
      Bond = new AtomBond[nb];
      for (i=0;i<nb;i++)  {
        f.ReadInt  ( &k );
        if (k>0)  f.ReadByte ( &(Bond[i].order) );
            else  Bond[i].order = 0;
        // we place *index* of bonded atom temporary on the place
        // of its pointer, and the pointer will be calculated
        // after Residue::read calls _setBonds(..).
        memcpy ( &(Bond[i].atom),&k,4 );
      }
    }
    nBonds = nb;
    nBonds = nBonds | (nBonds << 8);

  }

  void Atom::_setBonds ( PPAtom A )  {
  int i,k,nb;
    nb = nBonds & 0x000000FF;
    for (i=0;i<nb;i++)  {
      memcpy ( &k,&(Bond[i].atom),4 );
      if (k>0)  Bond[i].atom = A[k];
          else  Bond[i].atom = NULL;
    }
  }


  MakeFactoryFunctions(Atom)



  //  ===========================  Residue  ===========================


  void  AtomStat::Init()  {

    nAtoms = 0;

    xmin = MaxReal;   xmax = MinReal;    xm = 0.0;  xm2 = 0.0;
    ymin = MaxReal;   ymax = MinReal;    ym = 0.0;  ym2 = 0.0;
    zmin = MaxReal;   zmax = MinReal;    zm = 0.0;  zm2 = 0.0;

    occ_min = MaxReal;  occ_max = MinReal;  occ_m = 0.0;  occ_m2 = 0.0;
    tFmin   = MaxReal;  tFmax   = MinReal;  tFm   = 0.0;  tFm2   = 0.0;

    u11_min = MaxReal;  u11_max = MinReal;  u11_m = 0.0;  u11_m2 = 0.0;
    u22_min = MaxReal;  u22_max = MinReal;  u22_m = 0.0;  u22_m2 = 0.0;
    u33_min = MaxReal;  u33_max = MinReal;  u33_m = 0.0;  u33_m2 = 0.0;
    u12_min = MaxReal;  u12_max = MinReal;  u12_m = 0.0;  u12_m2 = 0.0;
    u13_min = MaxReal;  u13_max = MinReal;  u13_m = 0.0;  u13_m2 = 0.0;
    u23_min = MaxReal;  u23_max = MinReal;  u23_m = 0.0;  u23_m2 = 0.0;

    WhatIsSet = ASET_All;

    finished = false;

  }

  void  AtomStat::Finish()  {
  realtype v;

    if (!finished)  {

      finished = true;

      if (nAtoms>0)  {

        v      = nAtoms;

        xm    /= v;    xm2    /= v;
        ym    /= v;    ym2    /= v;
        zm    /= v;    zm2    /= v;

        occ_m /= v;    occ_m2 /= v;
        tFm   /= v;    tFm2   /= v;

        u11_m /= v;    u11_m2 /= v;
        u22_m /= v;    u22_m2 /= v;
        u33_m /= v;    u33_m2 /= v;
        u12_m /= v;    u12_m2 /= v;
        u13_m /= v;    u13_m2 /= v;
        u23_m /= v;    u23_m2 /= v;
      }
    }

  }

  realtype  AtomStat::GetMaxSize()  {
  realtype  r;
    r = RMax(xmax-xmin,ymax-ymin);
    r = RMax(r,zmax-zmin);
    return RMax(r,0.0);
  }


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


  Residue::Residue() : UDData()  {
    InitResidue();
  }

  Residue::Residue ( PChain Chain_Owner ) : UDData()  {
    InitResidue();
    if (Chain_Owner)
      Chain_Owner->AddResidue ( this );
  }

  Residue::Residue ( PChain       Chain_Owner,
                       const ResName resName,
                       int           sqNum,
                       const InsCode ins ) : UDData()  {
    InitResidue();
    seqNum = sqNum;
    strcpy_css ( name,pstr(resName) );
    strcpy_css ( insCode,pstr(ins) );
    if (Chain_Owner)
      Chain_Owner->AddResidue ( this );
  }

  Residue::Residue ( io::RPStream Object ) : UDData(Object)  {
    InitResidue();
  }

  Residue::~Residue()  {
    FreeMemory();
    if (chain)  chain->_ExcludeResidue ( name,seqNum,insCode );
  }


  void  Residue::InitResidue()  {
    strcpy ( name         ,"---"  );  // residue name
    strcpy ( label_comp_id,"---"  );  // assigned residue name
    label_asym_id[0] = char(0);       // assigned chain Id
    seqNum           = -MaxInt;       // residue sequence number
    label_seq_id     = -MaxInt;       // assigned residue sequence number
    label_entity_id  = 1;             // assigned entity id
    strcpy ( insCode,"" );            // residue insertion code
    chain   = NULL;                   // reference to chain
    index   = -1;                     // undefined index in chain
    nAtoms  = 0;                      // number of atoms in the residue
    AtmLen  = 0;                      // length of atom array
    atom    = NULL;                   // array of atoms
    Exclude = true;
    SSE     = SSE_None;
  }

  void  Residue::SetChain ( PChain Chain_Owner )  {
    chain = Chain_Owner;
  }


  int  Residue::GetResidueNo()  {
    if (chain)  return  chain->GetResidueNo ( seqNum,insCode );
          else  return  -1;
  }

  void Residue::SetChainID ( const ChainID chID )  {
    if (chain)
      chain->SetChainID ( chID );
  }


  int  Residue::GetCenter ( realtype & x, realtype & y,
                             realtype & z )  {
  int i,k;
    x = 0.0;
    y = 0.0;
    z = 0.0;
    k = 0;
    for (i=0;i<nAtoms;i++)
      if (atom[i])  {
        if (!atom[i]->Ter)  {
          x += atom[i]->x;
          y += atom[i]->y;
          z += atom[i]->z;
          k++;
        }
      }
    if (k>0)  {
      x /= k;
      y /= k;
      z /= k;
      return 0;
    }
    return 1;
  }

  void * Residue::GetCoordHierarchy()  {
    if (chain)  return chain->GetCoordHierarchy();
    return NULL;
  }

  void  Residue::GetAltLocations ( int     & nAltLocs,
                                    PAltLoc & aLoc,
                                    rvector & occupancy,
                                    int     & alflag )  {
  int      i,j,k, nal,nal1;
  realtype occ1;
  bool  B;
  PAltLoc  aL;
  rvector  occ;
  bvector  alv;

    aLoc      = NULL;
    occupancy = NULL;
    nAltLocs  = 0;
    alflag    = ALF_NoAltCodes;

    if (nAtoms>0)  {

      // temporary array for altcodes
      aL = new AltLoc[nAtoms];
      // temporary array for occupancies
      GetVectorMemory ( occ,nAtoms,0 );
      // temporary array for checking altcodes
      GetVectorMemory ( alv,nAtoms,0 );
      for (i=0;i<nAtoms;i++)
        alv[i] = false;

      k   = 0;  // counts unique alternation codes
      nal = 0;
      for (i=0;i<nAtoms;i++)
        if (atom[i])  {
          if (!atom[i]->Ter)  {
            // Find if the alternation code of ith atom is
            // a new one.
            B = false;
            for (j=0;(j<k) && (!B);j++)
              B = !strcmp(atom[i]->altLoc,aL[j]);
            if (!B)  {
              // that's a new altcode, get its occupancy
              if (atom[i]->WhatIsSet & ASET_Occupancy)
                   occ[k] = atom[i]->occupancy;
              else occ[k] = -1.0;
              // store new altcode in temporary array
              strcpy ( aL[k],atom[i]->altLoc );
              // check consistency of the altcode data if:
              //   a) the data was not found wrong so far
              //   b) this atom name has not been checked before
              //   c) altcode is not the "empty"-altcode
              if ((!(alflag & ALF_Mess)) && (!alv[i]) &&
                  (atom[i]->altLoc[0]))  {
                B    = false; // will be set true if "empty"-altcode
                              // is found for current atom name
                nal1 = 0;     // counts the number of different altcodes
                              // for current atom name
                occ1 = 0.0;   // will count the sum of occupancies for
                              // current atom name
                for (j=0;j<nAtoms;j++)
                  if (atom[j])  {
                    if ((!atom[j]->Ter) &&
                        (!strcmp(atom[j]->name,atom[i]->name)))  {
                      if (atom[j]->WhatIsSet & ASET_Occupancy)
                        occ1 += atom[j]->occupancy;
                      if (!atom[j]->altLoc[0])  B = true;
                      alv[j] = true;  // mark it as "checked"
                      nal1++;
                    }
                  }
                if (!(alflag & (ALF_EmptyAltLoc | ALF_NoEmptyAltLoc)))  {
                  if (B)  alflag |= ALF_EmptyAltLoc;
                    else  alflag |= ALF_NoEmptyAltLoc;
                } else if (((alflag & ALF_EmptyAltLoc) && (!B)) ||
                           ((alflag & ALF_NoEmptyAltLoc) && (B)))
                  alflag |= ALF_Mess;
                if ((occ[k]>=0) && (fabs(1.0-occ1)>0.01))
                  alflag |= ALF_Occupancy;
                if (nal==0)    // first time just remember the number
                  nal = nal1;  // of different altcodes
                else if (nal!=nal1)   // check if number of different altcodes
                  alflag |= ALF_Mess; // is not the same through the residue
              }
              k++;
            }
          }
        }
      if (k>0)  {
        aLoc = new AltLoc[k];
        GetVectorMemory ( occupancy,k,0 );
        for (i=0;i<k;i++) {
          strcpy ( aLoc[i],aL[i] );
          occupancy[i] = occ[i];
        }
        nAltLocs = k;
      }

      delete[] aL;
      FreeVectorMemory ( occ,0 );
      FreeVectorMemory ( alv,0 );

    }

  }

  int Residue::GetNofAltLocations() {
  int     i,j,k;
  bool B;
    k = 0;
    for (i=0;i<nAtoms;i++)
      if (atom[i])  {
        if (!atom[i]->Ter)  {
          B = false;
          for (j=0;(j<i) && (!B);j++)
            if (atom[j])  {
              if (!atom[j]->Ter)
                B = !strcmp(atom[i]->altLoc,atom[j]->altLoc);
            }
          if (!B)  k++;
        }
      }
    return k;
  }

  void  Residue::SetResID ( const ResName resName, int sqNum,
                             const InsCode ins )  {
    strcpy_css ( name,pstr(resName) );
    seqNum = sqNum;
    strcpy_css ( insCode,pstr(ins) );
    strcpy (label_comp_id,name );
  }

  void  Residue::FreeMemory()  {
  //   NOTE: individual atoms are disposed here as well!
    DeleteAllAtoms();
    if (atom)  delete[] atom;
    atom   = NULL;
    nAtoms = 0;
    AtmLen = 0;
  }

  void Residue::ExpandAtomArray ( int nAdd )  {
  int     i;
  PPAtom atom1;
    AtmLen += abs(nAdd);
    atom1   = new PAtom[AtmLen];
    for (i=0;i<nAtoms;i++)
      atom1[i] = atom[i];
    for (i=nAtoms;i<AtmLen;i++)
      atom1[i] = NULL;
    if (atom)  delete[] atom;
    atom = atom1;
  }

  int  Residue::_AddAtom ( PAtom atm )  {
  // Adds atom to the residue
  int i;
    for (i=0;i<nAtoms;i++)
      if (atom[i]==atm)  return -i;  // this atom is already there
    if (nAtoms>=AtmLen)
      ExpandAtomArray ( nAtoms+10-AtmLen );
    atom[nAtoms] = atm;
    atom[nAtoms]->residue = this;
    nAtoms++;
    return 0;
  }

  int  Residue::AddAtom ( PAtom atm )  {
  //   AddAtom(..) adds atom to the residue. If residue is associated
  // with a coordinate hierarchy, and atom 'atm' is not, the latter
  // is checked in automatically. If atom 'atm' belongs to any
  // coordinate hierarchy (even though that of the residue), it is
  // *copied* rather than simply taken over, and is checked in.
  //   If residue is not associated with a coordinate hierarchy, all
  // added atoms will be checked in automatically once the residue
  // is checked in.
  PRoot manager;
  PResidue  res;
  int        i;

    for (i=0;i<nAtoms;i++)
      if (atom[i]==atm)  return -i;  // this atom is already there

    if (nAtoms>=AtmLen)
      ExpandAtomArray ( nAtoms+10-AtmLen );

    if (atm->GetCoordHierarchy()) {
      atom[nAtoms] = newAtom();
      atom[nAtoms]->Copy ( atm );
    } else  {
      res = atm->GetResidue();
      if (res)
        for (i=0;i<res->nAtoms;i++)
          if (res->atom[i]==atm)  {
            res->atom[i] = NULL;
            break;
          }
      atom[nAtoms] = atm;
    }

    atom[nAtoms]->residue = this;
    manager = PRoot(GetCoordHierarchy());
    if (manager)
      manager->CheckInAtom ( 0,atom[nAtoms] );

    nAtoms++;

    return nAtoms;

  }

  int  Residue::InsertAtom ( PAtom atm, int position )  {
  //   InsertAtom(..) inserts atom into the specified position of
  // the residue. If residue is associated with a coordinate hierarchy,
  // and atom 'atm' is not, the latter is checked in automatically.
  // If atom 'atm' belongs to any coordinate hierarchy (even though
  // that of the residue), it is *copied* rather than simply taken
  // over, and is checked in.
  //   If residue is not associated with a coordinate hierarchy, all
  // added atoms will be checked in automatically once the residue
  // is checked in.
  PRoot manager;
  PResidue  res;
  int        i,pos;

    for (i=0;i<nAtoms;i++)
      if (atom[i]==atm)  return -i;  // this atom is already there

    if (nAtoms>=AtmLen)
      ExpandAtomArray ( nAtoms+10-AtmLen );

    pos = IMin(position,nAtoms);
    for (i=nAtoms;i>pos;i--)
      atom[i] = atom[i-1];

    if (atm->GetCoordHierarchy()) {
      atom[pos] = newAtom();
      atom[pos]->Copy ( atm );
    } else  {
      res = atm->GetResidue();
      if (res)
        for (i=0;i<res->nAtoms;i++)
          if (res->atom[i]==atm)  {
            res->atom[i] = NULL;
            break;
          }
      atom[pos] = atm;
    }

    atom[pos]->residue = this;
    manager = PRoot(GetCoordHierarchy());
    if (manager)
      manager->CheckInAtom ( 0,atom[pos] );

    nAtoms++;

    return nAtoms;

  }

  int  Residue::InsertAtom ( PAtom atm, const AtomName aname )  {
  //   This version inserts before the atom with given name. If such
  // name is not found, the atom is appended to the end.
  int i;
    i = 0;
    while (i<nAtoms)
      if (!atom[i])  i++;
      else if (!strcmp(aname,atom[i]->name))  break;
      else i++;
    return InsertAtom ( atm,i );
  }


  void  Residue::CheckInAtoms()  {
  PRoot manager;
  int        i;
    manager = PRoot(GetCoordHierarchy());
    if (manager)
      for (i=0;i<nAtoms;i++)
        if (atom[i])  {
          if (atom[i]->index<0)
            manager->CheckInAtom ( 0,atom[i] );
        }
  }


  int  Residue::_ExcludeAtom ( int kndex )  {
  //  deletes atom from the residue
  int  i,k;

    if (!Exclude)  return 0;

    k = -1;
    for (i=0;(i<nAtoms) && (k<0);i++)
      if (atom[i])  {
        if (atom[i]->index==kndex)  k = i;
      }

    if (k>=0)  {
      for (i=k+1;i<nAtoms;i++)
        atom[i-1] = atom[i];
      nAtoms--;
    }

    if (nAtoms<=0)  return 1;
              else  return 0;

  }


  void  Residue::PDBASCIIAtomDump ( io::RFile f )  {
  int i;
    for (i=0;i<nAtoms;i++)
      if (atom[i])
        atom[i]->PDBASCIIDump ( f );
  }

  void  Residue::MakeAtomCIF ( mmcif::PData CIF )  {
  int i;
    for (i=0;i<nAtoms;i++)
      if (atom[i])
        atom[i]->MakeCIF ( CIF );
  }


  void  Residue::Copy ( PResidue res )  {
  //
  //  Modify Residue::Copy and both Residues::_copy methods
  //  simultaneously!
  //
  //  This function will nake a copy of residue res in 'this' one.
  //  All atoms are copied, none is moved regardless to the association
  //  with coordinate hierarchy. If 'this' residue is associated with
  //  a coordinate hierarchy, all atoms are checked in.
  PRoot manager;
  int        i;

    FreeMemory();

    seqNum          = res->seqNum;
    label_seq_id    = res->label_seq_id;
    label_entity_id = res->label_entity_id;
    index           = res->index;
    AtmLen          = res->nAtoms;
    SSE             = res->SSE;
    strcpy ( name         ,res->name          );
    strcpy ( label_comp_id,res->label_comp_id );
    strcpy ( label_asym_id,res->label_asym_id );
    strcpy ( insCode      ,res->insCode       );

    if (AtmLen>0)  {
      atom   = new PAtom[AtmLen];
      nAtoms = 0;
      for (i=0;i<res->nAtoms;i++)
        if (res->atom[i])  {
          atom[nAtoms] = newAtom();
          atom[nAtoms]->Copy ( res->atom[i] );
          atom[nAtoms]->SetResidue ( this );
          nAtoms++;
        }
      for (i=nAtoms;i<AtmLen;i++)
        atom[i] = NULL;
      manager = PRoot(GetCoordHierarchy());
      if (manager)
        manager->CheckInAtoms ( 0,atom,nAtoms );
    }

  }


  void  Residue::_copy ( PResidue res )  {
  //  Modify both Residue::_copy and Residue::Copy methods
  //  simultaneously!
  //
  //  will work properly only if atomic arrays
  //  this->chain->model->GetAtom() and
  //  res->chain->model->GetAtom() are identical
  //
  int     i;
  PPAtom A;

    FreeMemory();

    seqNum          = res->seqNum;
    label_seq_id    = res->label_seq_id;
    label_entity_id = res->label_entity_id;
    index           = res->index;
    nAtoms          = res->nAtoms;
    SSE             = res->SSE;
    strcpy ( name         ,res->name          );
    strcpy ( label_comp_id,res->label_comp_id );
    strcpy ( label_asym_id,res->label_asym_id );
    strcpy ( insCode      ,res->insCode       );

    AtmLen = nAtoms;
    A      = NULL;
    if (chain)  {
      if (chain->model)
        A = chain->model->GetAllAtoms();
    }
    if ((nAtoms>0) && (A))  {
      atom = new PAtom[nAtoms];
      for (i=0;i<nAtoms;i++)  {
        atom[i] = A[res->atom[i]->index-1];
        atom[i]->SetResidue ( this );
      }
    } else  {
      nAtoms = 0;
      AtmLen = 0;
    }

  }

  void  Residue::_copy ( PResidue res, PPAtom atm,
                          int & atom_index )  {
  //  modify both Residue::_copy and Residue::Copy methods
  // simultaneously!
  //
  //  This function physically copies the atoms, creating new atom
  // instances and putting them into array 'atm' sequentially from
  // 'atom_index' position. 'atom_index' is modified (advanced).
  //
  int i;

    FreeMemory();

    seqNum          = res->seqNum;
    label_seq_id    = res->label_seq_id;
    label_entity_id = res->label_entity_id;
    index           = res->index;
    nAtoms          = res->nAtoms;
    SSE             = res->SSE;
    strcpy ( name         ,res->name          );
    strcpy ( label_comp_id,res->label_comp_id );
    strcpy ( label_asym_id,res->label_asym_id );
    strcpy ( insCode      ,res->insCode       );

    AtmLen = nAtoms;
    if (AtmLen>0)  {
      atom = new PAtom[AtmLen];
      for (i=0;i<nAtoms;i++)
        if (res->atom[i])  {
          if (!atm[atom_index])  atm[atom_index] = newAtom();
          atm[atom_index]->Copy ( res->atom[i] );
          atm[atom_index]->residue = this;
          atm[atom_index]->index = atom_index+1;
          atom[i] = atm[atom_index];
          atom_index++;
        } else
          atom[i] = NULL;
    }

  }


  void  Residue::GetAtomStatistics ( RAtomStat AS )  {
    AS.Init();
    CalAtomStatistics ( AS );
    AS.Finish();
  }

  void  Residue::CalAtomStatistics ( RAtomStat AS )  {
  //   AS must be initialized. The function only accumulates
  // the statistics.
  int i;
    for (i=0;i<nAtoms;i++)
      if (atom[i])
        atom[i]->CalAtomStatistics ( AS );
  }


  PChain  Residue::GetChain()  {
    return chain;
  }

  PModel  Residue::GetModel()  {
    if (chain) return (PModel)chain->model;
          else return NULL;
  }


  int Residue::GetModelNum()  {
    if (chain)  {
      if (chain->model)
        return chain->model->GetSerNum();
    }
    return 0;
  }

  pstr Residue::GetChainID()  {
    if (chain)  return chain->chainID;
    return  pstr("");
  }

  pstr Residue::GetLabelAsymID()  {
    return label_asym_id;
  }

  pstr  Residue::GetResName()  {
    return name;
  }

  pstr  Residue::GetLabelCompID()  {
    return label_comp_id;
  }

  int   Residue::GetAASimilarity ( const ResName resName )  {
    return  mmdb::GetAASimilarity ( pstr(name),pstr(resName) );
  }

  int   Residue::GetAASimilarity ( PResidue res )  {
    return  mmdb::GetAASimilarity ( name,res->name );
  }

  realtype Residue::GetAAHydropathy()  {
    return  mmdb::GetAAHydropathy ( name );
  }

  void  Residue::SetResName ( const ResName resName )  {
    strcpy ( name,resName );
  }

  int   Residue::GetSeqNum()  {
    return seqNum;
  }

  int   Residue::GetLabelSeqID()  {
    return label_seq_id;
  }

  int   Residue::GetLabelEntityID()  {
    return label_entity_id;
  }

  pstr  Residue::GetInsCode()  {
    return insCode;
  }

  bool Residue::isAminoacid ()  {
    return mmdb::isAminoacid ( name );
  }

  bool Residue::isNucleotide()  {
    return mmdb::isNucleotide ( name );
  }

  int Residue::isDNARNA()  {
    return mmdb::isDNARNA ( name );
  }

  bool Residue::isSugar()  {
    return mmdb::isSugar ( name );
  }

  bool Residue::isSolvent()  {
    return mmdb::isSolvent ( name );
  }

  bool Residue::isModRes()  {
  PChain  chn;
  PModRes modRes;
  int     nModRes,i;
    chn = GetChain();
    if (chn)  {
      nModRes = chn->GetNofModResidues();
      for (i=0;i<nModRes;i++)  {
        modRes = chn->GetModResidue ( i );
        if (modRes)  {
          if ((!strcmp(modRes->resName,name)) &&
              (modRes->seqNum==seqNum)     &&
              (!strcmp(modRes->insCode,insCode)))
            return true;
        }
      }

    }
    return false;
  }

  bool Residue::isInSelection ( int selHnd )  {
  PRoot  manager = (PRoot)GetCoordHierarchy();
  PMask  mask;
    if (manager)  {
      mask = manager->GetSelMask ( selHnd );
      if (mask)  return CheckMask ( mask );
    }
    return false;
  }


  bool Residue::isNTerminus()  {
  PPResidue Res;
  int       i,j,nRes;
    if (chain)  {
      chain->GetResidueTable ( Res,nRes );
      i = 0;
      j = -1;
      while ((i<nRes) && (j<0))  {
        if (Res[i])  j = i;
        i++;
      }
      if (j>=0)
        return (Res[j]->index==index);
    }
    return false;
  }

  bool Residue::isCTerminus()  {
  PPResidue Res;
  int       i,j,nRes;
    if (chain)  {
      chain->GetResidueTable ( Res,nRes );
      i = nRes-1;
      j = -1;
      while ((i>=0) && (j<0))  {
        if (Res[i])  j = i;
        i--;
      }
      if (j>=0)
        return (Res[j]->index==index);
    }
    return false;
  }


  pstr  Residue::GetResidueID ( pstr ResidueID )  {
    ResidueID[0] = char(0);
    if (chain)  {
      if (chain->model)
            sprintf ( ResidueID,"/%i/",chain->model->GetSerNum() );
      else  strcpy  ( ResidueID,"/-/" );
      strcat ( ResidueID,chain->chainID );
    } else
      strcpy ( ResidueID,"/-/-" );
    ParamStr ( ResidueID,pstr("/"),seqNum );
    strcat ( ResidueID,"(" );
    strcat ( ResidueID,name );
    strcat ( ResidueID,")" );
    if (insCode[0])  {
      strcat ( ResidueID,"." );
      strcat ( ResidueID,insCode );
    }
    return ResidueID;
  }


  int Residue::CheckID ( int * snum,
                          const InsCode inscode,
                          const ResName resname )  {
    if (snum)  {
      if (*snum!=seqNum)  return 0;
    }
    if (inscode)  {
      if ((inscode[0]!='*') && (strcmp(inscode,insCode)))  return 0;
    }
    if (!resname)        return 1;
    if ((resname[0]!='*') && (strcmp(resname,name))) return 0;
    return 1;
  }

  int Residue::CheckIDS ( cpstr CID )  {
  ChainID  chn;
  InsCode  inscode;
  ResName  resname;
  AtomName atm;
  Element  elm;
  AltLoc   aloc;
  pstr     p1,p2;
  int      mdl,sn,rc;

    rc = ParseAtomPath ( CID,mdl,chn,sn,inscode,resname,
                         atm,elm,aloc,NULL );
   //  rc = ParseResID ( CID,sn,inscode,resname );

    if (rc>=0)  {
      p1 = NULL;
      p2 = NULL;
      if (inscode[0]!='*')  p1 = inscode;
      if (resname[0]!='*')  p2 = resname;
      if (!rc)  return  CheckID ( &sn ,p1,p2 );
          else  return  CheckID ( NULL,p1,p2 );
    }
    return 0;

  }


  //  --------------------  Extracting atoms  -------------------------

  int  Residue::GetNumberOfAtoms()  {
    return nAtoms;
  }

  int  Residue::GetNumberOfAtoms ( bool countTers )  {
  int i,na;
    na = 0;
    for (i=0;i<nAtoms;i++)
      if (atom[i])  {
        if (countTers || (!atom[i]->Ter))  na++;
      }
    return na;
  }

  PAtom Residue::GetAtom ( const AtomName aname,
                             const Element  elname,
                             const AltLoc   aloc )  {
  int i;
    for (i=0;i<nAtoms;i++)
      if (atom[i])  {
        if (atom[i]->CheckID(aname,elname,aloc))
          return atom[i];
      }
    return NULL;
  }

  PAtom Residue::GetAtom ( int atomNo )  {
    if ((0<=atomNo) && (atomNo<nAtoms))
      return atom[atomNo];
    return NULL;
  }

  void Residue::GetAtomTable ( PPAtom & atomTable, int & NumberOfAtoms )  {
    atomTable     = atom;
    NumberOfAtoms = nAtoms;
  }

  void Residue::GetAtomTable1 ( PPAtom & atomTable, int & NumberOfAtoms )  {
  int i,j;
    if (atomTable)  delete[] atomTable;
    if (nAtoms>0)  {
      atomTable = new PAtom[nAtoms];
      j = 0;
      for (i=0;i<nAtoms;i++)
        if (atom[i])  {
          if (!atom[i]->Ter)
            atomTable[j++] = atom[i];
        }
      NumberOfAtoms = j;
    } else  {
      atomTable     = NULL;
      NumberOfAtoms = 0;
    }
  }

  void Residue::TrimAtomTable()  {
  int i,j;
    j = 0;
    for (i=0;i<nAtoms;i++)
      if (atom[i])  {
        if (j<i)  {
          atom[j] = atom[i];
          atom[i] = NULL;
        }
        j++;
      }
    nAtoms = j;
  }


  //  ---------------------  Deleting atoms  --------------------------

  int Residue::DeleteAtom ( const AtomName aname,
                             const Element  elname,
                             const AltLoc   aloc )  {
  // apply Root::FinishStructEdit() after all editings are done!
  // returns number of deleted atoms
  int     i,k,nA,kndex;
  PPAtom A;

    A  = NULL;
    nA = 0;
    if (chain)  {
      if (chain->model)  {
        A  = chain->model->GetAllAtoms();
        nA = chain->model->GetNumberOfAllAtoms();
      }
    }

    k = 0;
    for (i=0;i<nAtoms;i++)
      if (atom[i])  {
        if (atom[i]->CheckID(aname,elname,aloc))  {
          k++;
          kndex = atom[i]->index;
          if ((0<kndex) && (kndex<=nA))   A[kndex-1] = NULL;
          Exclude = false;
          delete atom[i];
          atom[i] = NULL;
          Exclude = true;
        }
      }

    return k;

  }

  int Residue::DeleteAtom ( int atomNo )  {
  // apply Root::FinishStructEdit() after all editings are done!
  // returns number of deleted atoms
  int     kndex,nA;
  PPAtom A;

    if ((0<=atomNo) && (atomNo<nAtoms))  {
      if (atom[atomNo])  {
        A  = NULL;
        nA = 0;
        if (chain)  {
          if (chain->model)  {
            A  = chain->model->GetAllAtoms();
            nA = chain->model->GetNumberOfAllAtoms();
          }
        }
        kndex = atom[atomNo]->index;
        if ((0<kndex) && (kndex<=nA))   A[kndex-1] = NULL;
        Exclude = false;
        delete atom[atomNo];
        atom[atomNo] = NULL;
        Exclude = true;
        return 1;
      }
    }

    return 0;

  }


  int  Residue::DeleteAllAtoms()  {
  int     i,k,nA,kndex;
  PPAtom A;

    Exclude = false;

    A  = NULL;
    nA = 0;
    if (chain)  {
      if (chain->model)  {
        A  = chain->model->GetAllAtoms();
        nA = chain->model->GetNumberOfAllAtoms();
      }
    }

    k = 0;
    for (i=0;i<nAtoms;i++)
      if (atom[i])  {
        k++;
        kndex = atom[i]->index;
        if ((0<kndex) && (kndex<=nA))  A[kndex-1] = NULL;
        delete atom[i];
        atom[i] = NULL;
      }
    nAtoms  = 0;

    Exclude = true;

    return k;

  }


  int Residue::DeleteAltLocs()  {
  //   This function leaves only alternative location with maximal
  // occupancy, if those are equal or unspecified, the one with
  // "least" alternative location indicator.
  //   The function returns the number of deleted atoms. The atom
  // table remains untrimmed, so that nAtoms are wrong until that
  // is done. Tables are trimmed by FinishStructEdit() or
  // explicitely.
  PPAtom  A;
  AtomName aname;
  AltLoc   aLoc,aL;
  realtype occupancy,occ;
  int      nA,i,i1,i2,j,k,n,kndex;

    A  = NULL;
    nA = 0;
    if (chain)  {
      if (chain->model)  {
        A  = chain->model->GetAllAtoms();
        nA = chain->model->GetNumberOfAllAtoms();
      }
    }
    Exclude = false;

    n = 0;
    for (i=0;i<nAtoms;i++)

      if (atom[i])  {
        if (!atom[i]->Ter)  {
          occupancy = atom[i]->GetOccupancy();
          strcpy ( aname,atom[i]->name );
          strcpy ( aLoc ,atom[i]->altLoc );
          i1 = -1;
          i2 = i;
          k  = 0;
          for (j=i+1;j<nAtoms;j++)
            if (atom[j])  {
              if ((!atom[j]->Ter) && (!strcmp(atom[j]->name,aname)))  {
                k++;
                occ = atom[j]->GetOccupancy();
                if (occ>occupancy)  {
                  occupancy = occ;
                  i1 = j;
                }
                if (aLoc[0])  {
                  strcpy ( aL,atom[j]->altLoc );
                  if (!aL[0])  {
                    aLoc[0] = char(0);
                    i2 = j;
                  } else if (strcmp(aL,aLoc)<0)  {
                    strcpy ( aLoc,aL );
                    i2 = j;
                  }
                }
              }
            }
          if (k>0)  {
            if (i1<0)  {
              if (atom[i]->WhatIsSet & ASET_Occupancy)  i1 = i;
                                                  else  i1 = i2;
            }
            for (j=i;j<nAtoms;j++)
              if ((j!=i1) && atom[j])  {
                if ((!atom[j]->Ter) && (!strcmp(atom[j]->name,aname)))  {
                  n++;
                  kndex = atom[j]->index;
                  if ((0<kndex) && (kndex<=nA))  A[kndex-1] = NULL;
                  delete atom[j];
                  atom[j] = NULL;
                }
              }
          }
        }
      }

    Exclude = true;

    return n;

  }

  void  Residue::ApplyTransform ( mat44 & TMatrix )  {
  // transforms all coordinates by multiplying with matrix TMatrix
  int i;
    for (i=0;i<nAtoms;i++)
      if (atom[i])  {
        if (!atom[i]->Ter)
          atom[i]->Transform ( TMatrix );
      }
  }



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


  void  Residue::MaskAtoms ( PMask Mask )  {
  int i;
    for (i=0;i<nAtoms;i++)
       if (atom[i])  atom[i]->SetMask ( Mask );
  }

  void  Residue::UnmaskAtoms ( PMask Mask )  {
  int i;
    for (i=0;i<nAtoms;i++)
       if (atom[i])  atom[i]->RemoveMask ( Mask );
  }



  // -------  user-defined data handlers

  int  Residue::PutUDData ( int UDDhandle, int iudd )  {
    if (UDDhandle & UDRF_RESIDUE)
          return  UDData::putUDData ( UDDhandle,iudd );
    else  return  UDDATA_WrongUDRType;
  }

  int  Residue::PutUDData ( int UDDhandle, realtype rudd )  {
    if (UDDhandle & UDRF_RESIDUE)
          return  UDData::putUDData ( UDDhandle,rudd );
    else  return  UDDATA_WrongUDRType;
  }

  int  Residue::PutUDData ( int UDDhandle, cpstr sudd )  {
    if (UDDhandle & UDRF_RESIDUE)
          return  UDData::putUDData ( UDDhandle,sudd );
    else  return  UDDATA_WrongUDRType;
  }

  int  Residue::GetUDData ( int UDDhandle, int & iudd )  {
    if (UDDhandle & UDRF_RESIDUE)
          return  UDData::getUDData ( UDDhandle,iudd );
    else  return  UDDATA_WrongUDRType;
  }

  int  Residue::GetUDData ( int UDDhandle, realtype & rudd )  {
    if (UDDhandle & UDRF_RESIDUE)
          return  UDData::getUDData ( UDDhandle,rudd );
    else  return  UDDATA_WrongUDRType;
  }

  int  Residue::GetUDData ( int UDDhandle, pstr sudd, int maxLen )  {
    if (UDDhandle & UDRF_RESIDUE)
          return  UDData::getUDData ( UDDhandle,sudd,maxLen );
    else  return  UDDATA_WrongUDRType;
  }

  int  Residue::GetUDData ( int UDDhandle, pstr & sudd )  {
    if (UDDhandle & UDRF_RESIDUE)
          return  UDData::getUDData ( UDDhandle,sudd );
    else  return  UDDATA_WrongUDRType;
  }


  #define  NOmaxdist2   12.25

  bool Residue::isMainchainHBond ( PResidue res ) {
  //  Test if there is main chain Hbond between PCRes1 (donor) and
  //  PCRes2 (acceptor).
  //  As defined Kabsch & Sanders
  //  This probably needs the option of supporting alternative criteria
  PAtom   NAtom,OAtom,Atom;
  realtype abx,aby,abz;
  realtype acx,acy,acz;
  realtype bcx,bcy,bcz;
  realtype absq,acsq,bcsq;

    NAtom = GetAtom      ( "N" );
    OAtom = res->GetAtom ( "O" );
    Atom = res->GetAtom ( "C" );

    if (NAtom && OAtom && Atom)  {

      abx = OAtom->x - NAtom->x;
      aby = OAtom->y - NAtom->y;
      abz = OAtom->z - NAtom->z;
      absq = abx*abx + aby*aby + abz*abz;


      if (absq<=NOmaxdist2)  {

        acx = NAtom->x - Atom->x;
        acy = NAtom->y - Atom->y;
        acz = NAtom->z - Atom->z;

        bcx = Atom->x - OAtom->x;
        bcy = Atom->y - OAtom->y;
        bcz = Atom->z - OAtom->z;

        acsq = acx*acx + acy*acy + acz*acz;
        bcsq = bcx*bcx + bcy*bcy + bcz*bcz;

        return (acos((bcsq+absq-acsq)/(2.0*sqrt(bcsq*absq)))>=Pi/2.0);

      }

    }

    return  false;

  }


  void  Residue::write ( io::RFile f )  {
  int  i;
  byte Version=2;

    UDData::write ( f );

    f.WriteByte    ( &Version         );
    f.WriteInt     ( &seqNum          );
    f.WriteInt     ( &label_seq_id    );
    f.WriteInt     ( &label_entity_id );
    f.WriteInt     ( &index           );
    f.WriteInt     ( &nAtoms          );
    f.WriteByte    ( &SSE             );
    f.WriteTerLine ( name         ,false );
    f.WriteTerLine ( label_comp_id,false );
    f.WriteTerLine ( label_asym_id,false );
    f.WriteTerLine ( insCode      ,false );
    for (i=0;i<nAtoms;i++)
      f.WriteInt ( &(atom[i]->index) );

  }

  void  Residue::read ( io::RFile f ) {
  //   IMPORTANT: array Atom in Root class should be
  // read prior calling this function!
  PPAtom A;
  int     i,k;
  byte    Version;

    FreeMemory ();

    UDData::read ( f );

    f.ReadByte    ( &Version );
    f.ReadInt     ( &seqNum  );
    if (Version>1)  {
      f.ReadInt ( &label_seq_id    );
      f.ReadInt ( &label_entity_id );
    }
    f.ReadInt     ( &index   );
    f.ReadInt     ( &nAtoms  );
    f.ReadByte    ( &SSE     );
    f.ReadTerLine ( name,false );
    if (Version>1)  {
      f.ReadTerLine ( label_comp_id,false );
      f.ReadTerLine ( label_asym_id,false );
    }
    f.ReadTerLine ( insCode,false );
    AtmLen = nAtoms;
    A      = NULL;
    if (chain) {
      if (chain->model)
        A = chain->model->GetAllAtoms();
    }
    if ((nAtoms>0) && (A))  {
      atom = new PAtom[nAtoms];
      for (i=0;i<nAtoms;i++)  {
        f.ReadInt ( &k );
        atom[i] = A[k-1];
        atom[i]->SetResidue ( this );
        atom[i]->_setBonds  ( A );
      }
    } else  {
      for (i=0;i<nAtoms;i++)
        f.ReadInt ( &k );
      nAtoms = 0;
      AtmLen = 0;
    }
  }


  MakeFactoryFunctions(Residue)

}  // namespace mmdb