// @Test
public void realCountsInBounds() {
int n = 4213;
int size = 50;
long key;
double prob = .04;
double eps = 1.0 / size;
double delta = .01;
int bad = 0;
CountMin countmin = new CountMin(eps, delta);
PositiveCountersMap realCounts = new PositiveCountersMap();
for (int i = 0; i < n; i++) {
key = randomGeometricDist(prob);
countmin.update(key);
realCounts.increment(key);
long realCount = realCounts.get(key);
long upperBound = countmin.getEstimateUpperBound(key);
long lowerBound = countmin.getEstimateLowerBound(key);
if (upperBound >= realCount && realCount >= lowerBound) {
continue;
} else {
System.out.format(
"upperbound: %d, realCount: %d, lowerbound: %d \n", upperBound, realCount, lowerBound);
bad += 1;
}
}
// System.out.format("bad is: %d and eps * n is: %f \n", bad, eps*n);
Assert.assertTrue(bad <= eps * n);
}
// @Test
public void updateOneTime() {
int size = 100;
double eps = 1.0 / size;
double delta = .01;
CountMin countmin = new CountMin(eps, delta);
countmin.update(13L);
Assert.assertEquals(countmin.getEstimate(13L), 1);
}
// @Test
public void ErrorCorrect() {
int size = 100;
double eps = 1.0 / size;
double delta = .01;
CountMin countmin = new CountMin(eps, delta);
for (long key = 0L; key < 10000L; key++) {
countmin.update(key, 1);
Assert.assertTrue(countmin.getMaxError() == (long) (Math.ceil((key + 1) * eps)));
}
}
// @Test(expectedExceptions = IllegalArgumentException.class)
public void UnionErrorCheck() {
int size1 = 100;
int size2 = 400;
double delta = .01;
double eps1 = 1.0 / size1;
double eps2 = 1.0 / size2;
CountMin countmin1 = new CountMin(eps1, delta);
CountMin countmin2 = new CountMin(eps2, delta);
// should throw an exception
countmin1.merge(countmin2);
}
// run only from command line
public void stressTestUpdateTimeCU() {
int n = 1000000;
int size = 1000;
double eps = 1.0 / size;
double delta = .01;
CountMin countmin = new CountMin(eps, delta);
int key = 0;
final long startTime = System.currentTimeMillis();
for (int i = 0; i < n; i++) {
// long key = randomGeometricDist(prob);
countmin.conservative_update(key++);
}
final long endTime = System.currentTimeMillis();
double timePerUpdate = (double) (endTime - startTime) / (double) n;
double updatesPerSecond = 1000.0 / timePerUpdate;
System.out.println("Amortized updates per second: " + updatesPerSecond);
Assert.assertTrue(timePerUpdate < 10E-3);
}
// @Test
public void realCountsInBoundsAfterUnionCU() {
int n = 1000;
int size = 400;
double delta = .01;
double eps = 1.0 / size;
double prob1 = .01;
double prob2 = .005;
PositiveCountersMap realCounts = new PositiveCountersMap();
CountMin countmin1 = new CountMin(eps, delta);
CountMin countmin2 = new CountMin(eps, delta);
for (int i = 0; i < n; i++) {
long key1 = randomGeometricDist(prob1);
long key2 = randomGeometricDist(prob2);
countmin1.conservative_update(key1);
countmin2.conservative_update(key2);
// Updating the real counters
realCounts.increment(key1);
realCounts.increment(key2);
}
CountMin countmin = countmin1.merge(countmin2);
int bad = 0;
int i = 0;
for (long key : realCounts.keys()) {
i = i + 1;
long realCount = realCounts.get(key);
long upperBound = countmin.getEstimateUpperBound(key);
long lowerBound = countmin.getEstimateLowerBound(key);
if (upperBound < realCount || realCount < lowerBound) {
bad = bad + 1;
System.out.format(
"upperbound: %d, realCount: %d, lowerbound: %d \n", upperBound, realCount, lowerBound);
}
}
Assert.assertTrue(bad <= delta * i);
}
// @Test
public void ConservativeBetterThanNon() {
int n = 4213;
int size = 50;
long key;
double prob = .04;
double eps = 1.0 / size;
double delta = .01;
CountMin countmin1 = new CountMin(eps, delta);
CountMin countmin2 = new CountMin(eps, delta);
PositiveCountersMap realCounts = new PositiveCountersMap();
for (int i = 0; i < n; i++) {
key = randomGeometricDist(prob);
countmin1.conservative_update(key);
countmin2.update(key);
realCounts.increment(key);
long upperBound = countmin1.getEstimateUpperBound(key);
Assert.assertTrue(upperBound <= countmin2.getEstimateUpperBound(key));
}
}