TEST_F(EwmaTest, testInitialValue) {
Ewma<FakeClock> ewma(std::chrono::seconds(5), 0);
ASSERT_EQ(ewma.estimate(), 0.0);
Ewma<FakeClock> ewma2(std::chrono::seconds(5), 50);
ASSERT_EQ(ewma2.estimate(), 50.0);
}
TEST_F(EwmaTest, testConstantValue) {
Ewma<FakeClock> ewma(std::chrono::seconds(5), 0);
auto target = 100.0;
for (int i = 0; i < 100; i++) {
ewma.add(target);
FakeClock::advance(std::chrono::seconds(1));
}
ASSERT_NEAR(ewma.estimate(), target, target * 0.1 / 100);
}
void stats__add_sample(struct stats *self, unsigned long sample)
{
if (self->nr_samples++ != 0) {
self->avg = ewma(self->avg, sample, 9);
if (sample > self->max)
self->max = sample;
if (sample < self->min)
self->min = sample;
} else
self->avg = self->min = self->max = sample;
}
int
main (void) {
struct iw_stat iws;
static float qual = 0.00;
iw_getstat(&iws);
qual = ewma(qual, iws.stat.qual.qual, 0 /* meter decay */ / 100.0);
printf("%.2f\n", qual);
printf("%d\n", iws.range.max_qual.qual);
printf("%0.f%% %.2f %.2f\n", (1e2 * qual)/iws.range.max_qual.qual, iws.dbm.signal, iws.dbm.noise);
return 0;
}
TEST_F(EwmaTest, testHalfLife) {
auto halfLife = std::chrono::seconds(5);
auto initial = 100;
Ewma<FakeClock> ewma(halfLife, initial);
auto previous = ewma.estimate();
auto target2 = 1000.0;
FakeClock::advance(halfLife);
ewma.add(target2);
auto expectedValue =
previous + (target2 - previous) / 2; // half of the difference
ASSERT_NEAR(ewma.estimate(), expectedValue, expectedValue * 0.1 / 100);
}
TEST_F(EwmaTest, testChangeInConstantValue) {
Ewma<FakeClock> ewma(std::chrono::seconds(5), 0);
auto target = 100.0;
for (int i = 0; i < 100; i++) {
ewma.add(target);
FakeClock::advance(std::chrono::seconds(1));
}
auto target2 = 1000.0;
for (int i = 0; i < 100; i++) {
ewma.add(target2);
FakeClock::advance(std::chrono::seconds(1));
}
// Should converge to the second target
ASSERT_NEAR(ewma.estimate(), target2, target2 * 0.1 / 100);
}
