This is statist.c in view mode; [Download] [Up]
#include "freeze.h"
#include "lz.h"
/* This program calculates the distribution of the matched strings'
positions and lengths using nearly the same code as `freeze'.
*/
#define N_POS 62
#define T (N_POS * 2 - 1)
#define R (T - 1)
#define update(c) (freq[c]++)
long in_count, bytes_out;
long indc_count;
short reduceflag = 0, greedy = 0;
int lens[F2+1];
u_short bits[9];
short prnt[T];
unsigned long freq[T];
short used[T];
void freeze(), StartHuff();
#ifndef INT_SIG
void
#endif
giveres();
int main(argc, argv) char ** argv; {
argv++;
while (argc > 1) {
if (**argv == '-') {
if ((*argv)[1] == 'g') {
argc--; argv++;
greedy++;
} else
break;
} else
break;
}
if(argc != 1) {
fprintf(stderr, "Usage: statist [-g] < sample_file\n");
fprintf(stderr, "Press INTR to display current values\n");
exit(0);
}
signal(SIGINT, giveres);
#ifdef MSDOS
setmode(fileno(stdin), O_BINARY); /* Oh this MS-DOS ... */
#endif /* MSDOS */
freeze();
giveres();
return 0;
}
unsigned long isqrt(val)
unsigned long val;
{
unsigned long result = 0;
unsigned long side = 0;
unsigned long left = 0;
int digit = 0;
int i;
for (i=0; i<sizeof(unsigned long)*4; i++)
{
left = (left << 2) + (val >> 30);
val <<= 2;
if (left >= side*2 + 1)
{
left -= side*2+1;
side = (side+1)*2;
result <<= 1;
result |= 1;
}
else
{
side *= 2;
result <<= 1;
}
}
return result;
}
/* Prints the (current) values of tunable parameters. Uncertainty is
the number of missequencings (algorithm assumes the probabilities
of references decrease uniformly when distance increases). Ideally
it should be 0, but somewhat about 5 or less denotes the given 8 values
could improve the compression rate when using them.
*/
#ifndef INT_SIG
void
#endif
giveres() {
u_short c;
register int i, j, k, pr, f, average, sum;
unsigned long cumul, sigma2;
short r, percent;
signal(SIGINT, giveres);
newtry:
StartHuff(N_POS);
pr = f = 0;
i = N_POS;
r = N_POS * 2 - 2;
while (i <= r) {
j = findmin(i);
k = findmin(i);
freq[i] = freq[j] + freq[k];
prnt[j] = prnt[k] = i++;
}
for (c = 1; c <= 6; c++) bits[c] = 0;
for(c = 0; c < N_POS; c++) {
j = 0;
k = c;
do j++; while ((k = prnt[k]) != r);
if (j <= 6)
bits[j]++;
if (j < pr)
f += pr - j;
pr = j;
}
k = bits[1] + bits[2] + bits[3] + bits[4] +
bits[5] + bits[6];
k = 62 - k; /* free variable length codes for 7 & 8 bits */
j = 128 * bits[1] + 64 * bits[2] + 32 * bits[3] +
16 * bits[4] + 8 * bits[5] + 4 * bits[6];
j = 256 - j; /* free byte images for these codes */
/* Equation:
bits[7] + bits[8] = k
2 * bits[7] + bits[8] = j
*/
j -= k;
if (j < 0 || k < j) {
printf("Huffman tree has more than 8 levels, reducing...\n");
for (i = 0; i < N_POS; i++)
if (!freq[i])
freq[i] = 1;
else if (reduceflag)
freq[i] = (freq[i] + 1) / 2;
reduceflag = 1;
goto newtry;
} else {
bits[7] = j;
bits[8] = k - j;
printf("%d %d %d %d %d %d %d %d (uncertainty = %d)\n",
bits[1], bits[2], bits[3], bits[4],
bits[5], bits[6], bits[7], bits[8], f);
}
sum = 0; cumul = 0;
for(i = 3; i <= F2; i++) {
cumul += (unsigned long) i * lens[i];
sum += lens[i];
}
sum || sum++;
printf("Average match length: %d.%02d\n",
average = cumul / sum, i = cumul * 100 / sum % 100);
if (i >= 50) average++;
j = sum;
percent = 0;
for (i = F2; i >= 3; i--) {
static pcs[] = { 999, 995, 990, 970, 950, 900, 800, 700, 500 };
j -= lens[i];
newpcs:
if (j <= sum * pcs[percent] / 1000) {
printf("Percentile %d.%d: %d\n",
pcs[percent] / 10, pcs[percent] % 10, i);
if (percent == sizeof(pcs)/sizeof(int) - 1)
break;
else {
percent++;
goto newpcs;
}
}
}
for (sigma2 = 0, i = 3; i <= F2; i++)
sigma2 += (unsigned long)(i - average)*(i - average)*lens[i];
sigma2 = sigma2 * 100 / sum;
j = (int)isqrt(sigma2);
printf("Sigma: %d.%1d\n", j / 10, j % 10);
fflush(stdout);
}
void freeze ()
{
register u_short i, len, r, s;
register short c;
StartHuff(0);
InitTree();
s = 0;
r = N2 - F2;
for (i = s; i < r; i++)
text_buf[i] = ' ';
for (len = 0; len < F2 && (c = getchar()) != EOF; len++)
text_buf[r + len] = c;
in_count = len;
for (i = 0; i <= F2; i++)
InsertNode(r + i - F2);
while (len != 0) {
Get_Next_Match(r,1);
if (match_length > len)
match_length = len;
if (match_length <= THRESHOLD) {
match_length = 1;
} else if (greedy) {
lens[match_length] ++;
update((u_short)match_position >> 7);
} else {
register u_short orig_length, orig_position;
orig_length = match_length;
orig_position = match_position;
DeleteNode(s);
Next_Char(N2, F2);
Get_Next_Match(r,2);
if (match_length > len) match_length = len;
if (orig_length > match_length) {
lens[orig_length] ++;
update((u_short)orig_position >> 7);
match_length = orig_length - 1;
} else {
lens[match_length] ++;
update(match_position >> 7);
}
}
for (i = 0; i < match_length &&
(c = getchar()) != EOF; i++) {
DeleteNode(s);
text_buf[s] = c;
if (s < F2 - 1)
text_buf[s + N2] = c;
s = (s + 1) & (N2 - 1);
r = (r + 1) & (N2 - 1);
InsertNode(r);
}
in_count += i;
if ((in_count > indc_count)) {
fprintf(stderr, "%5dK\b\b\b\b\b\b", in_count / 1024);
fflush (stderr);
indc_count += 4096;
}
while (i++ < match_length) {
DeleteNode(s);
s = (s + 1) & (N2 - 1);
r = (r + 1) & (N2 - 1);
if (--len) InsertNode(r);
}
}
}
void StartHuff(beg) {
int i;
for (i = beg; i < N_POS * 2 - 1; i++)
freq[i] = 0;
for (i = 0; i < N_POS * 2 - 1; i++)
used[i] = prnt[i] = 0;
}
int findmin(range) {
long min = (1 << 30) - 1, argmin = -1, i;
for (i = 0; i < range; i++) {
if(!used[i] && freq[i] < min)
min = freq[argmin = i];
}
used[argmin] = 1;
return argmin;
}
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.