void test_is_correctible () {
int row, col;
assert (is_correctible(INPUT2, 4, &row, &col) != 0);
assert (row == 2);
assert (col == 3);
assert (is_correctible(INPUT3, 4, &row, &col) == 0);
}
int main () {
int m[MAX][MAX];
do {
int n, i, j;
scanf ("%d", &n);
if (0 == n)
break;
/* read the matrix */
for (i = 0; i < n; i++) {
for (j = 0; j < n; j++) {
scanf ("%d ", &(m[i][j]));
}
}
if (has_parity(m, n)) {
printf ("OK\n");
} else {
int row, col;
if (is_correctible(m, n, &row, &col)) {
printf ("Change bit (%d,%d)\n", row, col);
} else {
printf ("Corrupt\n");
}
}
} while (1);
return 0;
}
//uses is_correctible instead of the actual reed_solomon codec to make it faster
float message_pass_rate_sim(int num_errors_min, int tries_max, float BER, int t)
{
int successes = 0;
int errors = 0;
int tries = 0;
while(errors < num_errors_min)
{
raw_data rd;
rd.length = 128 + 2*t;
rd.data = (uint8_t*)alloc_named(rd.length, "message_pass_rate_sim rd");
unsigned int i;
for(i = 0; i < rd.length; i++)
rd.data[i] = rand();
raw_data ep = convolute(rd);
//interleaving not needed as errror insertion is AWGN- faster to not do it
//interleave(ep); //interleaves data in place
insert_errors2(ep.data, ep.length, BER);
//deinterleave(ep);
raw_data deconvoluted = deconvolute(ep, NULL);
if(is_correctible(rd, deconvoluted, t, 0))
{
successes++;
}
else
{
errors++;
}
dealloc(ep.data);
dealloc(deconvoluted.data);
dealloc(rd.data);
if(tries >= tries_max)
break;
tries++;
}
return (float)successes / ((float)successes + (float)errors);
}
//tests the methods used encoding and decoding, uses insert_errors2 to accomodate any bit rate
float message_pass_rate(int num_tests, float BER)
{
int successes = 0;
int errors = 0;
int tries = 0;
int wrong1 = 0, wrong2 = 0;
//for(unsigned int i = 0; i < num_tests; i++)
while(errors < 100)
{
raw_data rd;
rd.length = 64;
rd.data = (uint8_t*)alloc_named(rd.length, "message_pass_rate rd");
unsigned int i;
for(i = 0; i < 64; i++)
rd.data[i] = rand();
int t = 2; //PYTHON//
//p = make_packet(rd);
//encoded_packet ep = encode(&p); //currently convolutional- subject to change
raw_data rs_encoded = rs_encode(rd, t);
raw_data ep = convolute(rs_encoded);
interleave(ep); //interleaves data in place
insert_errors2(ep.data, ep.length, BER);
deinterleave(ep);
raw_data deconvoluted = deconvolute(ep, NULL);
int isc = is_correctible(rs_encoded, deconvoluted, t, 0);
raw_data decoded;
rs_decode(deconvoluted, &decoded, t, NULL);
//q = decode(ep, NULL);
if(rd.length != decoded.length)
{
printf("lengths are not the same!\n");
printf("rd.length = %i, decoded.length = %i\n", rd.length, decoded.length);
}
if(!memcmp(decoded.data, rd.data, rd.length))
{
if(!isc)
wrong1++;
//if(!isc)
// is_correctible(rs_encoded, deconvoluted, t, 1);
//assert(isc);
successes++;
}
else
{
if(isc)
wrong2++;
//assert(!isc);
errors++;
}
dealloc(ep.data);
dealloc(rs_encoded.data);
dealloc(deconvoluted.data);
dealloc(decoded.data);
dealloc(rd.data);
if(tries >= num_tests)
{
printf("tries = %i, errors = %i\n", tries, errors);
break;
}
tries++;
}
//return (float)successes / (float)num_tests;
printf("wrong1 = %i\n", wrong1);
printf("wrong2 = %i\n", wrong2);
printf("tests = %i\n", successes + errors);
return (float)successes / ((float)successes + (float)errors);
}