--- /dev/null
+#include <cstdlib>
+
+#include "nibblevector.h"
+#include "../misc/utils.h"
+
+
+namespace CSA
+{
+
+
+NibbleVector::NibbleVector(std::ifstream& file) :
+ BitVector(file)
+{
+}
+
+NibbleVector::NibbleVector(Encoder& encoder, usint universe_size) :
+ BitVector(encoder, universe_size)
+{
+}
+
+NibbleVector::~NibbleVector()
+{
+}
+
+//--------------------------------------------------------------------------
+
+usint
+NibbleVector::reportSize() const
+{
+ usint bytes = sizeof(*this);
+ bytes += BitVector::reportSize();
+ return bytes;
+}
+
+//--------------------------------------------------------------------------
+
+NibbleVector::Iterator::Iterator(const NibbleVector& par) :
+ BitVector::Iterator(par),
+ use_rle(false)
+{
+}
+
+NibbleVector::Iterator::~Iterator()
+{
+}
+
+// FIXME gap encoding for all operations
+
+usint
+NibbleVector::Iterator::rank(usint value, bool at_least)
+{
+ const NibbleVector& par = (const NibbleVector&)(this->parent);
+
+ if(value >= par.size) { return par.items; }
+
+ this->valueLoop(value);
+
+ usint idx = this->sample.first + this->cur + 1;
+ if(!at_least && this->val > value)
+ {
+ idx--;
+ }
+ if(at_least && this->val < value)
+ {
+ this->getSample(this->block + 1);
+ idx = this->sample.first + this->cur + 1;
+ }
+ return idx;
+}
+
+usint
+NibbleVector::Iterator::select(usint index)
+{
+ const NibbleVector& par = (const NibbleVector&)(this->parent);
+
+ if(index >= par.items) { return par.size; }
+ this->getSample(this->sampleForIndex(index));
+
+ usint lim = index - this->sample.first;
+ while(this->cur < lim)
+ {
+ this->val += this->buffer.readNibbleCode();
+ usint temp = this->buffer.readNibbleCode();
+ this->val += temp - 1;
+ this->cur += temp;
+ }
+ if(this->cur > lim)
+ {
+ this->run = this->cur - lim;
+ this->cur -= this->run;
+ this->val -= this->run;
+ }
+
+ return this->val;
+}
+
+usint
+NibbleVector::Iterator::selectNext()
+{
+ if(this->cur >= this->block_items)
+ {
+ this->getSample(this->block + 1);
+ return this->val;
+ }
+
+ this->cur++;
+ if(this->run > 0)
+ {
+ this->val++;
+ this->run--;
+ }
+ else
+ {
+ this->val += this->buffer.readNibbleCode();
+ this->run = this->buffer.readNibbleCode() - 1;
+ }
+
+ return this->val;
+}
+
+pair_type
+NibbleVector::Iterator::valueAfter(usint value)
+{
+ const NibbleVector& par = (const NibbleVector&)(this->parent);
+
+ if(value >= par.size) { return pair_type(par.size, par.items); }
+
+ this->valueLoop(value);
+
+ if(this->val < value)
+ {
+ this->getSample(this->block + 1);
+ }
+
+ return pair_type(this->val, this->sample.first + this->cur);
+}
+
+pair_type
+NibbleVector::Iterator::nextValue()
+{
+ if(this->cur >= this->block_items)
+ {
+ this->getSample(this->block + 1);
+ return pair_type(this->val, this->sample.first);
+ }
+
+ this->cur++;
+ if(this->run > 0)
+ {
+ this->val++;
+ this->run--;
+ }
+ else
+ {
+ this->val += this->buffer.readNibbleCode();
+ this->run = this->buffer.readNibbleCode() - 1;
+ }
+
+ return pair_type(this->val, this->sample.first + this->cur);
+}
+
+pair_type
+NibbleVector::Iterator::selectRun(usint index, usint max_length)
+{
+ usint value = this->select(index);
+
+ usint len = std::min(max_length, this->run);
+ this->run -= len; this->cur += len; this->val += len;
+
+ return pair_type(value, len);
+}
+
+pair_type
+NibbleVector::Iterator::selectNextRun(usint max_length)
+{
+ usint value = this->selectNext();
+
+ usint len = std::min(max_length, this->run);
+ this->run -= len; this->cur += len; this->val += len;
+
+ return pair_type(value, len);
+}
+
+bool
+NibbleVector::Iterator::isSet(usint value)
+{
+ const NibbleVector& par = (const NibbleVector&)(this->parent);
+
+ if(value >= par.size) { return false; }
+
+ this->valueLoop(value);
+
+ return (this->val == value);
+}
+
+usint
+NibbleVector::Iterator::countRuns()
+{
+ const NibbleVector& par = (const NibbleVector&)(this->parent);
+
+ if(par.items == 0) { return 0; }
+
+ usint runs = 1;
+ pair_type res = this->selectRun(0, par.items);
+ usint last = res.first + res.second;
+
+ while(last < par.size)
+ {
+ res = this->selectNextRun(par.items);
+ if(res.first < par.size && res.first > last + 1) { runs++; }
+ last = res.first + res.second;
+ }
+
+ return runs;
+}
+
+//--------------------------------------------------------------------------
+
+NibbleEncoder::NibbleEncoder(usint block_bytes, usint superblock_size) :
+ VectorEncoder(block_bytes, superblock_size)
+{
+}
+
+NibbleEncoder::~NibbleEncoder()
+{
+}
+
+void
+NibbleEncoder::setBit(usint value)
+{
+ this->setRun(value, 1);
+}
+
+// FIXME for gap encoding
+void
+NibbleEncoder::setRun(usint start, usint len)
+{
+ if(this->items == 0)
+ {
+ this->setFirstBit(start);
+ if(len > 1)
+ {
+ this->nibbleEncode(1, len - 1);
+ }
+ return;
+ }
+ if(start < this->size || len == 0) { return; }
+
+ // Write as much into the buffer as possible.
+ usint diff = start + 1 - this->size;
+ usint free_bits = this->buffer->bitsLeft();
+ usint code_bits = this->buffer->nibbleCodeLength(diff);
+ if(free_bits >= code_bits + 4) // At least a part of the run fits into the block.
+ {
+ free_bits -= code_bits;
+ usint run_bits = this->buffer->nibbleCodeLength(len);
+ if(run_bits <= free_bits)
+ {
+ this->nibbleEncode(diff, len);
+ return;
+ }
+
+ // Encode as much as possible and let the rest spill.
+ usint llen = (usint)1 << (3 * (free_bits / 4));
+ this->nibbleEncode(diff, llen);
+ len -= llen;
+
+ // A new sample will be added.
+ this->size++;
+ this->items++;
+ }
+ else
+ {
+ this->size = start + 1;
+ this->items++;
+ }
+
+ // Didn't fit into the block. A new sample & block required.
+ this->addNewBlock();
+ if(len > 1)
+ {
+ this->nibbleEncode(1, len - 1);
+ }
+}
+
+
+} // namespace CSA
projects / SXSI / TextCollection.git / blobdiff