include/types/block.h

   1 /*
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  35 #ifndef _block_h
  36 #define _block_h
  37
  38
  39 #include "idef.h"
  40
  41 #ifdef __cplusplus
  42 extern "C" {
  43 #endif
  44
  45 /* the block structure points into an array (usually of atom_ids).
  46    It is a list of starting indices for objects of consecutive ids, such
  47    as molecules.
  48    For example, if this block denotes molecules, then the first molecule
  49    ranges from index[0] to index[1]-1 in the atom list.
  50
  51    This makes the mapping from atoms to molecules O(Nmolecules) instead
  52    of O(Natoms) in size.  */
  53 typedef struct {
  54   int nr;                       /* The number of blocks                 */
  55   atom_id *index;               /* Array of indices (dim: nr+1)         */
  56   int nalloc_index;             /* The allocation size for index        */
  57 } t_block;
  58
  59 typedef struct {
  60   int nr;                       /* The number of blocks                 */
  61   atom_id *index;               /* Array of indices in a (dim: nr+1)    */
  62   int nra;                      /* The number of atoms                  */
  63   atom_id *a;                   /* Array of atom numbers in each group  */
  64                                 /* (dim: nra)                           */
  65                                 /* Block i (0<=i<nr) runs from          */
  66                                 /* index[i] to index[i+1]-1. There will */
  67                                 /* allways be an extra entry in index   */
  68                                 /* to terminate the table               */
  69   int nalloc_index;             /* The allocation size for index        */
  70   int nalloc_a;                 /* The allocation size for a            */
  71 } t_blocka;
  72
  73
  74 #ifdef __cplusplus
  75 }
  76 #endif
  77
  78 #endif