/* PRINT-CODE.C - Print a Low Density Parity Check code's matrices. *//* Copyright (c) 2000, 2001 by Radford M. Neal  * * Permission is granted for anyone to copy, use, or modify this program  * for purposes of research or education, provided this copyright notice  * is retained, and note is made of any changes that have been made.  * * This program is distributed without any warranty, express or implied. * As this program was written for research purposes only, it has not been * tested to the degree that would be advisable in any important application. * All use of this program 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){  char *gen_file;  int dprint;  int i, j;  dprint = 0;  if (argc>1 && strcmp(argv[1],"-d")==0)  { dprint = 1;    argc -= 1;    argv += 1;  }  if (!(gen_file = argv[1]) || argv[2])  { usage();  }  read_gen(gen_file,0,1);  switch (type)  {    case 's':     {       printf("\nGenerator matrix in %s (sparse representation):\n\n",gen_file);      printf("Column order (message bits at end):\n");      for (j = 0; j<N; j++)       { if (j%20==0) printf("\n");        printf(" %3d",cols[j]);      }      printf("\n\n");      printf("Row order:\n");      for (i = 0; i<M; i++)       { if (i%20==0) printf("\n");        printf(" %3d",rows[i]);       }      printf("\n\n");      if (dprint)      { mod2dense *Ld, *Ud;        Ld = mod2dense_allocate(M,M);        Ud = mod2dense_allocate(M,N);        mod2sparse_to_dense(L,Ld);        mod2sparse_to_dense(U,Ud);        printf("L:\n\n");        mod2dense_print(stdout,Ld);        printf("\n");        printf("U:\n\n");        mod2dense_print(stdout,Ud);        printf("\n");      }      else      { printf("L:\n\n");        mod2sparse_print(stdout,L);        printf("\n");        printf("U:\n\n");        mod2sparse_print(stdout,U);        printf("\n");      }           break;    }    case 'd': case 'm':    {      if (type=='d')      { printf("\nGenerator matrix in %s (dense representation):\n\n",gen_file);      }      if (type=='m')      { printf("\nGenerator matrix in %s (mixed representation):\n\n",gen_file);      }      printf("Column order (message bits at end):\n");      for (j = 0; j<N; j++)       { if (j%20==0) printf("\n");        printf(" %3d",cols[j]);      }      printf("\n\n");      printf (type=='d' ? "Inv(A) X B:\n\n" : "Inv(A):\n\n");      mod2dense_print(stdout,G);      printf("\n");      break;    }    default:     { fprintf(stderr,"Unknown type of generator matrix file\n");      exit(1);    }  }  return 0;}/* PRINT USAGE MESSAGE AND EXIT. */void usage(void){ fprintf(stderr,"Usage: print-gen [ -d ] gen-file\n");  exit(1);}