ga_io.c

关于遗传算法的一些见地。特别是关于简单遗传程序设计的实现。

  memcpy(&stable_size, buffer, sizeof(int));
  if (!ReadFile(file, buffer, sizeof(int), &nread, NULL) || nread < 1)
    dief("Unable to read data.  Error %d\n", GetLastError());
  memcpy(&num_chromosomes, buffer, sizeof(int));
  if (!ReadFile(file, buffer, sizeof(int), &nread, NULL) || nread < 1)
    dief("Unable to read data.  Error %d\n", GetLastError());
  memcpy(&len_chromosomes, buffer, sizeof(int));

/*
 * Allocate a new population structure.
 */
  pop = ga_population_new(stable_size, num_chromosomes, len_chromosomes);

/*
 * Got a population structure?
 */
  if ( !pop ) die("Unable to allocate population structure.");

/*
 * GA parameters.
 */
  if (!ReadFile(file, buffer, sizeof(double), &nread, NULL) || nread < 1)
    dief("Unable to read data.  Error %d\n", GetLastError());
  memcpy(&(pop->crossover_ratio), buffer, sizeof(double));
  if (!ReadFile(file, buffer, sizeof(double), &nread, NULL) || nread < 1)
    dief("Unable to read data.  Error %d\n", GetLastError());
  memcpy(&(pop->mutation_ratio), buffer, sizeof(double));
  if (!ReadFile(file, buffer, sizeof(double), &nread, NULL) || nread < 1)
    dief("Unable to read data.  Error %d\n", GetLastError());
  memcpy(&(pop->migration_ratio), buffer, sizeof(double));
  if (!ReadFile(file, buffer, sizeof(int), &nread, NULL) || nread < 1)
    dief("Unable to read data.  Error %d\n", GetLastError());
  memcpy(&(pop->allele_mutation_prob), buffer, sizeof(double));
  if (!ReadFile(file, buffer, sizeof(double), &nread, NULL) || nread < 1)
    dief("Unable to read data.  Error %d\n", GetLastError());
  memcpy(&(pop->allele_min_integer), buffer, sizeof(int));
  if (!ReadFile(file, buffer, sizeof(int), &nread, NULL) || nread < 1)
    dief("Unable to read data.  Error %d\n", GetLastError());
  memcpy(&(pop->allele_max_integer), buffer, sizeof(int));
  if (!ReadFile(file, buffer, sizeof(int), &nread, NULL) || nread < 1)
    dief("Unable to read data.  Error %d\n", GetLastError());
  memcpy(&(pop->allele_min_double), buffer, sizeof(double));
  if (!ReadFile(file, buffer, sizeof(double), &nread, NULL) || nread < 1)
    dief("Unable to read data.  Error %d\n", GetLastError());
  memcpy(&(pop->allele_max_double), buffer, sizeof(double));
  if (!ReadFile(file, buffer, sizeof(double), &nread, NULL) || nread < 1)
    dief("Unable to read data.  Error %d\n", GetLastError());
  memcpy(&(pop->scheme), buffer, sizeof(int));
  if (!ReadFile(file, buffer, sizeof(int), &nread, NULL) || nread < 1)
    dief("Unable to read data.  Error %d\n", GetLastError());
  memcpy(&(pop->elitism), buffer, sizeof(int));
  if (!ReadFile(file, buffer, sizeof(int), &nread, NULL) || nread < 1)
    dief("Unable to read data.  Error %d\n", GetLastError());
  memcpy(&(pop->island), buffer, sizeof(int));

/*
 * Callback handling.  Note that user-implemented functions currently
 * can't be handled in these files.
 * id = -1 - Unknown, external function.
 * id = 0  - NULL function.
 * id > 0  - GAUL defined function.
 */
  if (!ReadFile(file, buffer, 19*sizeof(int), &nread, NULL) || nread < 1)
    dief("Unable to read data.  Error %d\n", GetLastError());
  memcpy(&id, buffer, 19*sizeof(int));

  pop->generation_hook        = (GAgeneration_hook)  ga_funclookup_id_to_ptr(id[0]);
  pop->iteration_hook         = (GAiteration_hook)   ga_funclookup_id_to_ptr(id[1]);

  pop->data_destructor        = (GAdata_destructor)      ga_funclookup_id_to_ptr(id[2]);
  pop->data_ref_incrementor   = (GAdata_ref_incrementor) ga_funclookup_id_to_ptr(id[3]);

  pop->chromosome_constructor = (GAchromosome_constructor) ga_funclookup_id_to_ptr(id[4]);
  pop->chromosome_destructor  = (GAchromosome_destructor)  ga_funclookup_id_to_ptr(id[5]);
  pop->chromosome_replicate   = (GAchromosome_replicate)   ga_funclookup_id_to_ptr(id[6]);
  pop->chromosome_to_bytes    = (GAchromosome_to_bytes)    ga_funclookup_id_to_ptr(id[7]);
  pop->chromosome_from_bytes  = (GAchromosome_from_bytes)  ga_funclookup_id_to_ptr(id[8]);
  pop->chromosome_to_string   = (GAchromosome_to_string)   ga_funclookup_id_to_ptr(id[9]);

  pop->evaluate               = (GAevaluate)       ga_funclookup_id_to_ptr(id[10]);
  pop->seed                   = (GAseed)           ga_funclookup_id_to_ptr(id[11]);
  pop->adapt                  = (GAadapt)          ga_funclookup_id_to_ptr(id[12]);
  pop->select_one             = (GAselect_one)     ga_funclookup_id_to_ptr(id[13]);
  pop->select_two             = (GAselect_two)     ga_funclookup_id_to_ptr(id[14]);
  pop->mutate                 = (GAmutate)         ga_funclookup_id_to_ptr(id[15]);
  pop->crossover              = (GAcrossover)      ga_funclookup_id_to_ptr(id[16]);
  pop->replace                = (GAreplace)        ga_funclookup_id_to_ptr(id[17]);
  pop->rank                   = (GArank)           ga_funclookup_id_to_ptr(id[18]);

/*
 * Warn user of any unhandled data.
 */
  for (i=0; i<19; i++)
    if (id[i] == -1) count++;

  if (count>0)
    plog(LOG_NORMAL, "Unable to handle %d hook function%sspecified in population structure.", count, count==1?" ":"s ");

/*
 * Entity info.
 */
  for (i=0; i<size; i++)
    {
    gaul_read_entity_win32(file, pop);
    }

/*
 * Footer info.
 */
  if (!ReadFile(file, buffer, 4*sizeof(char), &nread, NULL) || nread < 1)
    dief("Unable to read data.  Error %d\n", GetLastError());
  if (strcmp("END", buffer)!=0) die("Corrupt population file?");

/*
 * Close file.
 */
  CloseHandle(file);

  plog(LOG_DEBUG, "Have read %d entities into population.", pop->size);

  return pop;
  }
#endif


/**********************************************************************
  ga_entity_write()
  synopsis:	Write an entity to disk.
		Note: Currently does not (and probably can not) store
		any of the userdata.
  parameters:	population *pop
		entity *entity
		char *fname
  return:	TRUE
  last updated: 07 Nov 2002
 **********************************************************************/

#ifndef WIN32
boolean ga_entity_write(population *pop, entity *entity, char *fname)
  {
  int		i;			/* Loop variable. */
  char		buffer[BUFFER_SIZE];	/* String buffer. */
  char		*format_str="FORMAT: GAUL ENTITY 001";	/* Format tag. */
  FILE		*fp;			/* Filehandle. */

/* Checks. */
  if ( !pop ) die("Null pointer to population structure passed.");
  if ( !entity ) die("Null pointer to entity structure passed.");
  if ( !fname ) die("Null pointer to filename passed.");

/*
 * Open output file.
 */
  if( !(fp=fopen(fname,"w")) )
    dief("Unable to open entity file \"%s\" for output.", fname);

/*
 * Write stuff.
 */
  fwrite(format_str, sizeof(char), strlen(format_str), fp);
  for (i=0; i<64; i++) buffer[i]='\0';
  snprintf(buffer, 64, "%s %s", GA_VERSION_STRING, GA_BUILD_DATE_STRING);
  fwrite(buffer, sizeof(char), 64, fp);

  gaul_write_entity_posix(fp, pop, entity);

  fwrite("END", sizeof(char), 4, fp); 

  fclose(fp);

  return TRUE;
  }
#else

boolean ga_entity_write(population *pop, entity *entity, char *fname)
  {
  int		i;			/* Loop variable. */
  char		buffer[BUFFER_SIZE];	/* String buffer. */
  char		*format_str="FORMAT: GAUL ENTITY 001";	/* Format tag. */
  HANDLE	file;			/* Filehandle. */
  DWORD		nwrote;			/* Number of bytes written. */

/* Checks. */
  if ( !pop ) die("Null pointer to population structure passed.");
  if ( !entity ) die("Null pointer to entity structure passed.");
  if ( !fname ) die("Null pointer to filename passed.");

/*
 * Open output file.
 */
  if ((file = CreateFile(fname, GENERIC_WRITE,
        0, 0, CREATE_NEW, 0, 0)) == INVALID_HANDLE_VALUE)
    dief("Unable to open entity file \"%s\" for output due to error %d.",
         fname, GetLastError());

/*
 * Write stuff.
 */
  if ( WriteFile(file, format_str, strlen(format_str)*sizeof(char), &nwrote, NULL)==0 )
    dief("Error writing %d\n", GetLastError());

  for (i=0; i<64; i++) buffer[i]='\0';
  snprintf(buffer, 64, "%s %s", GA_VERSION_STRING, GA_BUILD_DATE_STRING);
  if ( WriteFile(file, format_str, 64*sizeof(char), &nwrote, NULL)==0 )
    dief("Error writing %d\n", GetLastError());

  gaul_write_entity_win32(file, pop, entity);

  strncpy(buffer, "END\0", 4); 
  if ( WriteFile(file, format_str, 4*sizeof(char), &nwrote, NULL)==0 )
    dief("Error writing %d\n", GetLastError());

  CloseHandle(file);

  return TRUE;
  }
#endif


/**********************************************************************
  ga_entity_read()
  synopsis:	Read an entity from disk.
		Note: Currently does not (and probably can not) store
		any of the userdata.
  parameters:	population *pop
		entity *entity
		char *fname
  return:	TRUE
  last updated: 30 May 2002
 **********************************************************************/

#ifndef WIN32
/*
 * UNIX/POSIX version:
 */

entity *ga_entity_read(population *pop, char *fname)
  {
  char		buffer[BUFFER_SIZE];	/* String buffer. */
  char		*format_str="FORMAT: GAUL ENTITY 001";	/* Format tag. */
  char		format_str_in[32];	/* Input format tag. */
  FILE		*fp;			/* Filehandle. */
  entity	*entity;		/* Input entity. */

/* Checks. */
  if ( !pop ) die("Null pointer to population structure passed.");
  if ( !fname ) die("Null pointer to filename passed.");

/*
 * Open input file.
 */
  if( !(fp=fopen(fname,"r")) )
    dief("Unable to open entity file \"%s\" for input.", fname);

/*
 * Read stuff.
 */
  fread(format_str_in, sizeof(char), strlen(format_str), fp);
  if (strcmp(format_str, format_str_in)!=0) die("Incorrect format for entity file.");
  fread(buffer, sizeof(char), 64, fp);	/* Ignored. */

  entity = gaul_read_entity_posix(fp, pop);

  fread(buffer, sizeof(char), 4, fp); 
  if (strcmp("END", buffer)!=0) die("Corrupt population file?");

  fclose(fp);

  return entity;
  }

#else
/*
 * MS Windows version:
 */

entity *ga_entity_read(population *pop, char *fname)
  {
  char		buffer[BUFFER_SIZE];	/* String buffer. */
  char		*format_str="FORMAT: GAUL ENTITY 001";	/* Format tag. */
  char		format_str_in[32];	/* Input format tag. */
  HANDLE	file;			/* Filehandle. */
  entity	*entity;		/* Input entity. */
  DWORD		nread;			/* Number of bytes read. */

/* Checks. */
  if ( !pop ) die("Null pointer to population structure passed.");
  if ( !fname ) die("Null pointer to filename passed.");

/*
 * Open input file.
 */
  if ( (file = CreateFile(fname, GENERIC_READ,
        0, 0, OPEN_EXISTING, 0, 0)) == INVALID_HANDLE_VALUE )
    dief("Unable to open entity file \"%s\" for input due to error %d.",
         fname, GetLastError());

/*
 * Read stuff.
 */
  if (!ReadFile(file, format_str_in, strlen(format_str)*sizeof(char), &nread, NULL) && nread < 1)
    dief("Unable to open entity file \"%s\" for input due to error %d.",
         fname, GetLastError());

  if (strncmp(format_str, format_str_in, strlen(format_str))!=0)
    die("Incorrect format for entity file.");

  ReadFile(file, buffer, 64*sizeof(char), &nread, NULL);	/* Ignored. */

  entity = gaul_read_entity_win32(file, pop);

  if (!ReadFile(file, buffer, 4, &nread, NULL) && nread < 1)
    dief("Unable to open entity file \"%s\" for input due to error %d.",
         fname, GetLastError());

  if (strcmp("END", buffer)!=0) die("Corrupt population file?");

  CloseHandle(file);

  return entity;
  }
#endif