int dab_dct(Test **test,int irun)
{
double *dct;
unsigned int *input;
double *pvalues = NULL;
unsigned int i, j;
unsigned int len = (ntuple == 0) ? 256 : ntuple;
int rotAmount = 0;
unsigned int v = 1<<(rmax_bits-1);
double mean = (double) len * (v - 0.5);
/* positionCounts is only used by the primary test, and not by the
* fallback test.
*/
double *positionCounts;
/* The primary method is a chisq; we want expected counts of at least
* five. If the number of tsamples is too low for that, use the
* fallback method, which is doing kstest across the pvalues.
*/
int useFallbackMethod = (test[0]->tsamples > 5 * len) ? 0 : 1;
/* ptest, v, and sd are only used in the fall-back method, when
* tsamples is too small compared to ntuple.
*/
Xtest ptest;
double sd = sqrt((1.0/6.0) * len) * v;
dct = (double *) malloc(sizeof(double) * len);
input = (unsigned int *) malloc(sizeof(unsigned int) * len);
positionCounts = (double *) malloc(sizeof(double) * len);
if (useFallbackMethod) {
pvalues = (double *) malloc(sizeof(double) * len * test[0]->tsamples);
}
/* Zero out the counts initially. */
memset(positionCounts, 0, sizeof(double) * len);
test[0]->ntuple = len;
/* When used, the data is normalized first. */
ptest.y = 0.0;
ptest.sigma = 1.0;
/* Main loop runs tsamples times. During each iteration, a vector
* of length ntuple will be read from the generator, so a total of
* (tsamples * ntuple) words will be read from the RNG.
*/
for (j=0; j<test[0]->tsamples; j++) {
unsigned int pos = 0;
double max = 0;
/* Change the rotation amount after each quarter of the samples
* have been used.
*/
if (j != 0 && (j % (test[0]->tsamples / 4) == 0)) {
rotAmount += rmax_bits/4;
}
/* Read (and rotate) the actual rng words. */
for (i=0; i<len; i++) {
input[i] = gsl_rng_get(rng);
input[i] = RotL(input[i], rotAmount);
}
/* Perform the DCT */
fDCT2_fft(input, dct, len);
/* Adjust the first value (the DC coefficient). */
dct[0] -= mean;
dct[0] /= sqrt(2); // Experimental + guess; seems to be correct.
if (!useFallbackMethod) {
/* Primary method: find the position of the largest value. */
for (i=0; i<len; i++) {
if (fabs(dct[i]) > max) {
pos = i;
max = fabs(dct[i]);
}
}
/* And record it. */
positionCounts[pos]++;
} else {
/* Fallback method: convert all values to pvalues. */
for (i=0; i<len; i++) {
ptest.x = dct[i] / sd;
Xtest_eval(&ptest);
pvalues[j*len + i] = ptest.pvalue;
}
}
}
if (!useFallbackMethod) {
/* Primary method: perform a chisq test for uniformity
* of discrete counts. */
double p;
double *expected = (double *) malloc(sizeof(double) * len);
for (i=0; i<len; i++) {
expected[i] = (double) test[0]->tsamples / len;
}
p = chisq_pearson(positionCounts, expected, len);
test[0]->pvalues[irun] = p;
free(expected);
} else {
/* Fallback method: perform a ks test for uniformity of the
* continuous p-values. */
test[0]->pvalues[irun] = kstest(pvalues, len * test[0]->tsamples);
}
nullfree(positionCounts);
nullfree(pvalues); /* Conditional; only used in fallback */
nullfree(input);
nullfree(dct);
return(0);
}
int dab_filltree(Test **test,int irun) {
int size = (ntuple == 0) ? 32 : ntuple;
uint target = sizeof(targetData)/sizeof(double);
int startVal = (size / 2) - 1;
double *array = (double *) malloc(sizeof(double) * size);
double *counts, *expected;
int i, j;
double x;
uint start = 0;
uint end = 0;
uint rotAmount = 0;
double *positionCounts;
counts = (double *) malloc(sizeof(double) * target);
expected = (double *) malloc(sizeof(double) * target);
memset(counts, 0, sizeof(double) * target);
positionCounts = (double *) malloc(sizeof(double) * size/2);
memset(positionCounts, 0, sizeof(double) * size/2);
test[0]->ntuple = size;
test[1]->ntuple = size;
/* Calculate expected counts. */
for (i = 0; i < target; i++) {
expected[i] = targetData[i] * test[0]->tsamples;
if (expected[i] < 4) {
if (end == 0) start = i;
} else if (expected[i] > 4) end = i;
}
start++;
for (j = 0; j < test[0]->tsamples; j++) {
int ret;
memset(array, 0, sizeof(double) * size);
i = 0;
do {
uint v = gsl_rng_get(rng);
x = ((double) RotL(v, rotAmount)) / rmax_mask;
i++;
if (i > size * 2) {
test[0]->pvalues[irun] = 0;
return(0);
}
ret = insert(x, array, startVal);
} while (ret == -1);
positionCounts[ret/2]++;
counts[i-1]++;
if (j % (test[0]->tsamples/CYCLES) == 0) rotAmount++;
}
test[0]->pvalues[irun] = chisq_pearson(counts + start, expected + start, end - start);
for (i = 0; i < size/2; i++) expected[i] = test[0]->tsamples/(size/2);
test[1]->pvalues[irun] = chisq_pearson(positionCounts, expected, size/2);
nullfree(positionCounts);
nullfree(expected);
nullfree(counts);
nullfree(array);
return(0);
}