print-pchk.c

剑桥大学David J.C. MacKay 个人网站公布的2006年的代码

/* PRINT-PCHK.C - Print the parity check matrix for a code. */

/* Copyright (c) 2000, 2001 by Radford M. Neal 
 *
 * Permission is granted for anyone to copy, use, modify, or distribute this
 * program and accompanying programs and documents for any purpose, provided 
 * this copyright notice is retained and prominently displayed, along with
 * a note saying that the original programs are available from Radford Neal's
 * web page, and note is made of any changes made to the programs.  The
 * programs and documents are distributed without any warranty, express or
 * implied.  As the programs were written for research purposes only, they have
 * not been tested to the degree that would be advisable in any important
 * application.  All use of these programs is entirely at the user's own risk.
 */

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

#include "rand.h"
#include "alloc.h"
#include "open.h"
#include "mod2sparse.h"
#include "mod2dense.h"
#include "mod2convert.h"
#include "rcode.h"

void usage(void);


/* MAIN PROGRAM. */

int main
( int argc,
  char **argv
)
{
  mod2dense *D;
  mod2sparse *T;

  char *pchk_file;
  int dprint, trans;

  dprint = 0;
  trans = 0;

  for (;;)
  {
    if (argc>1 && strcmp(argv[1],"-d")==0)
    { dprint = 1;
      argc -= 1;
      argv += 1;
    }
    else if (argc>1 && strcmp(argv[1],"-t")==0)
    { trans = 1;
      argc -= 1;
      argv += 1;
    }
    else
    { break;
    }
  }

  if (!(pchk_file = argv[1]) || argv[2])
  { usage();
  }

  read_pchk(pchk_file);

  if (trans)
  { T = mod2sparse_allocate(N,M);
    mod2sparse_transpose(H,T);
  }

  if (dprint)
  { if (trans)
    { D = mod2dense_allocate(N,M);
      mod2sparse_to_dense(T,D);
      printf("\nTranspose of parity check matrix in %s (dense format):\n\n",
             pchk_file);
      mod2dense_print(stdout,D);
    }
    else
    { D = mod2dense_allocate(M,N);
      mod2sparse_to_dense(H,D);
      printf("\nParity check matrix in %s (dense format):\n\n",pchk_file);
      mod2dense_print(stdout,D);
    }
  }
  else /* sparse */
  { if (trans)
    { printf("\nTranspose of parity check matrix in %s (sparse format):\n\n",
             pchk_file);
      mod2sparse_print(stdout,T);
    }
    else
    { printf("\nParity check matrix in %s (sparse format):\n\n",pchk_file);
      mod2sparse_print(stdout,H);
    }
  }

  printf("\n");

  return 0;
}


/* PRINT USAGE MESSAGE AND EXIT. */

void usage(void)
{ fprintf(stderr,"Usage: print-pchk [ -d ] [ -t ] pchk-file\n");
  exit(1);
}