WSJT-X/lib/ldpc/make-pchk.c
Steven Franke 5ac886855d Add ldpc sandbox folder.
git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@6437 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
2016-01-25 00:04:21 +00:00

94 lines
2.0 KiB
C
Executable File

/* MAKE-PCHK.C - Make a parity check matrix explicitly. */
/* Copyright (c) 1995-2012 by Radford M. Neal.
*
* Permission is granted for anyone to copy, use, modify, and distribute
* these programs and accompanying documents for any purpose, provided
* this copyright notice is retained and prominently displayed, and note
* is made of any changes made to these programs. These 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 "alloc.h"
#include "intio.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 **bit_specs;
char *file;
FILE *f;
int i, j, k;
char junk;
if (!(file = argv[1])
|| !argv[2] || sscanf(argv[2],"%d%c",&M,&junk)!=1 || M<=0
|| !argv[3] || sscanf(argv[3],"%d%c",&N,&junk)!=1 || N<=0)
{ usage();
}
bit_specs = argv+4;
if (bit_specs[0]==0)
{ usage();
}
H = mod2sparse_allocate(M,N);
for (k = 0; bit_specs[k]!=0; k++)
{ if (sscanf(bit_specs[k],"%d:%d%c",&i,&j,&junk)!=2 || i<0 || j<0)
{ usage();
}
if (i>=M || j>=N)
{ fprintf(stderr,"Bit %d:%d is out of range\n",i,j);
exit(1);
}
mod2sparse_insert(H,i,j);
}
f = open_file_std(file,"wb");
if (f==NULL)
{ fprintf(stderr,"Can't create parity check file: %s\n",file);
exit(1);
}
intio_write(f,('P'<<8)+0x80);
if (ferror(f) || !mod2sparse_write(f,H) || fclose(f)!=0)
{ fprintf(stderr,"Error writing to parity check file %s\n",file);
exit(1);
}
return 0;
}
/* PRINT USAGE MESSAGE AND EXIT. */
void usage(void)
{ fprintf(stderr,"Usage: make-pchk pchk-file n-checks n-bits row:col ...\n");
exit(1);
}