// Build a waveform of type `type` with frequency `t` and amplitude `a` in `temp_cycle`,
// Then call swap_cycle() to replace `cycle` with `temp_cycle`.
void build_tone(float t, float a, enum TYPE type) {
temp_samples_per_cycle = (sample_rate / t);
sample_t scale = 2 * PI / temp_samples_per_cycle;
temp_cycle = (sample_t *) malloc(temp_samples_per_cycle * sizeof(sample_t));
if (temp_cycle == NULL) {
fprintf(stderr,"Memory allocation failed.\n");
exit(3);
}
int i;
for (i = 0; i < temp_samples_per_cycle; i++) {
switch(type) {
case Sine:
temp_cycle[i] = a * sin(i * scale);
break;
case Square:
temp_cycle[i] = a * sgn(sin(i * scale));
break;
case Triangle:
temp_cycle[i] = a * (asin(sin(i * scale)) / (PI / 2));
break;
case Sawtooth:
temp_cycle[i] = a * (2 * ((((float) i) / temp_samples_per_cycle) - floor(((float) i) / temp_samples_per_cycle)) - 1);
break;
}
}
swap_cycle();
}
void
StaticPersistence<D, CT, OT, E, Cmp>::
initialize(const Filtration& filtration)
{
order_.assign(filtration.size(), OrderElement());
rLog(rlPersistence, "Initializing persistence");
OffsetMap<typename Filtration::Index, iterator> om(filtration.begin(), begin());
for (typename Filtration::Index cur = filtration.begin(); cur != filtration.end(); ++cur)
{
Cycle z;
BOOST_FOREACH(const typename Filtration::Simplex& s, std::make_pair(cur->boundary_begin(), cur->boundary_end()))
z.push_back(index(om[filtration.find(s)]));
z.sort(ocmp_);
iterator ocur = om[cur];
swap_cycle(ocur, z);
set_pair(ocur, ocur);
}
}
void
StaticPersistence<D, CT, OT, E, Cmp>::
pair_simplices(iterator bg, iterator end, bool store_negative, const Visitor& visitor)
{
#if LOGGING
typename ContainerTraits::OutputMap outmap(order_);
#endif
// FIXME: need sane output for logging
rLog(rlPersistence, "Entered: pair_simplices");
for (iterator j = bg; j != end; ++j)
{
visitor.init(j);
rLog(rlPersistence, "Simplex %s", outmap(j).c_str());
Cycle z;
swap_cycle(j, z);
rLog(rlPersistence, " has boundary: %s", z.tostring(outmap).c_str());
// Sparsify the cycle by removing the negative elements
if (!store_negative)
{
typename OrderElement::Cycle zz;
BOOST_FOREACH(OrderIndex i, z)
if (i->sign()) // positive
zz.push_back(i);
z.swap(zz);
}
// --------------------------
CountNum(cPersistencePairBoundaries, z.size());
#ifdef COUNTERS
Count(cPersistencePair);
#endif // COUNTERS
while(!z.empty())
{
OrderIndex i = z.top(ocmp_); // take the youngest element with respect to the OrderComparison
rLog(rlPersistence, " %s: %s", outmap(i).c_str(), outmap(i->pair).c_str());
// TODO: is this even a meaningful assert?
AssertMsg(!ocmp_(i, index(j)),
"Simplices in the cycle must precede current simplex: (%s in cycle of %s)",
outmap(i).c_str(), outmap(j).c_str());
// i is not paired, so we pair j with i
if (iterator_to(i->pair) == iterator_to(i))
{
rLog(rlPersistence, " Pairing %s and %s with cycle %s",
outmap(i).c_str(), outmap(j).c_str(),
z.tostring(outmap).c_str());
set_pair(i, j);
swap_cycle(j, z);
set_pair(j, i);
CountNum(cPersistencePairCycleLength, j->cycle.size());
CountBy (cPersistencePairCycleLength, j->cycle.size());
break;
}
// update element
z.add(i->pair->cycle, ocmp_);
visitor.update(j, iterator_to(i));
rLog(rlPersistence, " new cycle: %s", z.tostring(outmap).c_str());
}
// if z was empty, so is (already) j->cycle, so nothing to do
visitor.finished(j);
rLog(rlPersistence, "Finished with %s: %s",
outmap(j).c_str(), outmap(j->pair).c_str());
}
