float
EditableDenseThreeDimensionalModel::getValueAt(size_t index, size_t n) const
{
Column c = getColumn(index);
if (n < c.size()) return c.at(n);
return m_minimum;
}
EditableDenseThreeDimensionalModel::Column
EditableDenseThreeDimensionalModel::expandAndRetrieve(size_t index) const
{
// See comment above m_trunc declaration in header
assert(index < m_data.size());
Column c = m_data.at(index);
if (index == 0) {
return c;
}
int trunc = (int)m_trunc[index];
if (trunc == 0) {
return c;
}
bool top = true;
int tdist = trunc;
if (trunc < 0) { top = false; tdist = -trunc; }
Column p = expandAndRetrieve(index - tdist);
int psize = p.size(), csize = c.size();
if (psize != m_yBinCount) {
std::cerr << "WARNING: EditableDenseThreeDimensionalModel::expandAndRetrieve: Trying to expand from incorrectly sized column" << std::endl;
}
if (top) {
for (int i = csize; i < psize; ++i) {
c.push_back(p.at(i));
}
} else {
// push_front is very slow on QVector -- but not enough to
// make it desirable to choose a different container, since
// QVector has all the other advantages for us. easier to
// write the whole array out to a new vector
Column cc(psize);
for (int i = 0; i < psize - csize; ++i) {
cc[i] = p.at(i);
}
for (int i = 0; i < csize; ++i) {
cc[i + (psize - csize)] = c.at(i);
}
return cc;
}
return c;
}
void
EditableDenseThreeDimensionalModel::truncateAndStore(size_t index,
const Column &values)
{
assert(index < m_data.size());
//std::cout << "truncateAndStore(" << index << ", " << values.size() << ")" << std::endl;
// The default case is to store the entire column at m_data[index]
// and place 0 at m_trunc[index] to indicate that it has not been
// truncated. We only do clever stuff if one of the clever-stuff
// tests works out.
m_trunc[index] = 0;
if (index == 0 ||
m_compression == NoCompression ||
values.size() != m_yBinCount) {
// given += values.size();
// stored += values.size();
m_data[index] = values;
return;
}
// Maximum distance between a column and the one we refer to as
// the source of its truncated values. Limited by having to fit
// in a signed char, but in any case small values are usually
// better
static int maxdist = 6;
bool known = false; // do we know whether to truncate at top or bottom?
bool top = false; // if we do know, will we truncate at top?
// If the previous column is not truncated, then it is the only
// candidate for comparison. If it is truncated, then the column
// that it refers to is the only candidate. Either way, we only
// have one possible column to compare against here, and we are
// being careful to ensure it is not a truncated one (to avoid
// doing more work recursively when uncompressing).
int tdist = 1;
int ptrunc = m_trunc[index-1];
if (ptrunc < 0) {
top = false;
known = true;
tdist = -ptrunc + 1;
} else if (ptrunc > 0) {
top = true;
known = true;
tdist = ptrunc + 1;
}
Column p = expandAndRetrieve(index - tdist);
int h = m_yBinCount;
if (p.size() == h && tdist <= maxdist) {
int bcount = 0, tcount = 0;
if (!known || !top) {
// count how many identical values there are at the bottom
for (int i = 0; i < h; ++i) {
if (values.at(i) == p.at(i)) ++bcount;
else break;
}
}
if (!known || top) {
// count how many identical values there are at the top
for (int i = h; i > 0; --i) {
if (values.at(i-1) == p.at(i-1)) ++tcount;
else break;
}
}
if (!known) top = (tcount > bcount);
int limit = h / 4; // don't bother unless we have at least this many
if ((top ? tcount : bcount) > limit) {
if (!top) {
// create a new column with h - bcount values from bcount up
Column tcol(h - bcount);
// given += values.size();
// stored += h - bcount;
for (int i = bcount; i < h; ++i) {
tcol[i - bcount] = values.at(i);
}
m_data[index] = tcol;
m_trunc[index] = -tdist;
return;
} else {
// create a new column with h - tcount values from 0 up
Column tcol(h - tcount);
// given += values.size();
// stored += h - tcount;
for (int i = 0; i < h - tcount; ++i) {
tcol[i] = values.at(i);
}
m_data[index] = tcol;
m_trunc[index] = tdist;
return;
}
}
}
// given += values.size();
// stored += values.size();
// std::cout << "given: " << given << ", stored: " << stored << " ("
// << ((float(stored) / float(given)) * 100.f) << "%)" << std::endl;
// default case if nothing wacky worked out
m_data[index] = values;
return;
}
